Weather technical

107 thoughts on “Weather technical

  1. Very pathetic situation of convection on both sides of peninsular seas, a clear indication of Elnino-like situation??

    Reason (as per my observations):
    Both SOI (ENSO-factor) & IOD are in decreasing trend, which is the indication of “weak-strength” in trade winds travelling towards Indian sub-continent.

    (1) Any convection developed by passage of equatorial waves (like MJO, ER, Kelvin, MRG) can not survive for long time and subsequently delays in tropical systems related to pre-monsoonal and monsoonal systems.
    (2) Tropical easterly jet stream will be weakened???

    When the situation will improve?
    Either of SOI or IOD has to increase (as ONI index crossed above +0.5)

    trade winds general figure:

  2. Role of SOI (trade wind factor) regarding BOB-systems:

    Whatever the -ve value in SOI is not the most worrying factor. Its the trend in SOI that matters most.

    Even super Elnino with SOI values below -20 exhibits occasional increase in SOI values. This phases of occasional increase in SOI will strengthen the trade winds and related convection over peninsular seas (hence strengthening of systems).

    Recent 2 scenarios in 2014: (even present situation also we are looking)
    Example 1: SOI occasional increasing trend in between 2 dropping phases at the time of Hudhud-2014, October 7-14 (No single agency expected hudhud can intensify to cat.4 (still controversy is there regarding its cat.5 super cyclonic strength).
    hudhud-2014 (October 7-14, 2014):

    Example 2: We have seen how pathetically died/blown off “the deep depression BOB 04 (November 5-8, 2014). Al weather models indicated that it will intensify to cat.3 or above cyclone. Even convection occupied entire BOB at early stage. But non-stop decrease in SOI slowly killed the system in the mid-way of strengthening.
    DD BOB 04 (November 5-8, 2014):

    (1) In both the cases IOD turned to dead “0”. But hudhud-2014 case increase in SOI makes the system so powerful. While in case of DD BOB04, SOI has decreased continuously in non-stop manner, hence it died off in mid-way without strengthening.

    This 2 quite controversial BOB-systems clearly tells the dominance role of trade winds generated by SOI.

    (2) Both BOB-systems initiated by combination of MJO & Kelvin waves.

  3. SWM-trough of axis is part of ITCZ, which is an imaginary line connecting the lowest MSLP (see figure).

    Over Indian sub-continent, western end will be over NWIndia-Pakistan border and eastern end will be over N/NW/NE BOB.

    This is not a rigid line. But it will oscillate southerly or northerly from normal position depending on active & break monsoon periods (influenced by tropical low-level jet stream (LLJ), which in turn depend on ENSO & IOD conditions)


  4. The latest strong dip in SOI makes the recent active convection (initiated by ER & Kelvin combinations) not to develop into any kind of system (even LPA formation) despite models’ continuous forecast of strong system on either side of peninsular seas.

    Now I think SOI going to touch the bottom line of the latest decreasing phase. SO expecting it will start increasing from May 20th onwards. Accidently (or nature’s pre-plan) MJO will entering Indian ocean.

    So now I am too confident (based on raoos model: ) BOB will hoist a D/DD/Minimal cyclone after May 20th (which models are not showing).

    (1) I think its better for the models the variation in SOI in their inputs (if not using) to get stable output especially regarding “Boss of Bays (BOB)”.
    (2) The cyclone cross section indicates the trade wind (SOI as parameter) as input at lower-levels. This is the power of trade wind strength (nothing but SOI increasing).
    (3) All equatorial low-level winds can be considered as trade winds (don’t confuse that trade winds must come from only E/NE/SE direction). I will consider SWM also as indirect trade wind component due to its turn towards SW-direction on entering northern hemisphere from southern hemisphere during SWM season..

    1. cyclone cross section image 1:
    2. cyclone cross section image 1:
    3. trade winds general figure:
    4. latest dip in SOI:

  5. NEM 2015 Prospects::

    One more findings about NEM and ELNINO relationship.

    14 ELNINO years, NEM successful in 6 years.
    1951, 53, 57, 63, 65, 69, 72, 82, 87, 91, 97, 2002, 2004 & 2009

    1. NEM Failures – 1951, 1953, 1957, 1963 & 1965 ELNINO developed after May and before August and Neutral IOD.
    1A. 1982, 1991 & 2004, in these years ELNINO developed before May or After May and Before August.

    2. NEM Successful Year – Example – 1969, 1972, 1987, 1997, 2002, 2004 & 2009.
    A. If there is no Positive IOD during ELNINO year, then NEM Fails.
    B. If ELNINO set after or before May, even though we have Positive IOD then also NEM Fails.
    C. If ELNINO set in by May and if we have Positive IOD during onset of SWM or before July then NEM Successful.

    Bullet Points:
    1. In 1969 ELNINO arrived late in October, hence NEM was excess.

    2. 1972 & 1997 when ELNINO was arrived in May and Positive IOD superseded and gave excess rainfall during NEM.

    3. In 1987, since ELNINO has started in 1986 september itself and continued till 1987 december, it was an longer time ELNINO year, ELNINO started to weaken September 1987, Positive IOD emerged in August, hence it is an unusual year.

    4. In 2002 & 2009 ELNINO developed in August and was weak , hence there was no impact.

    To Summarize:
    Hence If ELNINO arrives in May and Positive IOD developed during the same period then NEM is excess or normal.
    If ELNINO develops prior to May or after May and before August then those years NEM Fails even though Positive IOD.

    2015 Prospect:
    In 2015 the same thing happening as ELNIN developing in May and Positive IOD likely by May or June. Hence NEM 2015 should be surplus.

  6. How SWM was successful in 1997 even when the Strongest ELNINO of history emerged.

    In 1997, the central to east pacific was hotter and the above normal sst was
    prevailing. Since the the descending air flow was shifted away from the Indian subcontinent the monsoon was unaffected.

    During the 2002 event, however, the warming was concentrated in the central Pacific. With the warming in the middle of the Pacific, the descending air flow reached much farther west, closer to the Indian subcontinent. The result was drought.

    Hence the heating portion of NINO regions are important.

    ELNINO values alone not the deciding factor for influencing SWM.

    So far the above normal SST was prevailing across the Pacific from East to West, but latest SST anomaly suggests that the SST will decrease over West Pacific, hence the air will not descend over Indian Ocean, this is good news.

    • Partha, please try to compare 2 similar type Elninos (whether regular or Modoki). 2002 is Elnino-modoki and 1997 is a classical. Then how can we compare Elnino with respect to SWM.

      In 1997, its +veIOD (during may, june & july) with respect to ENSO-strength, which made SWM successful.
      In 2002, its -ve IOD (during may, june & july) with respect to Elnino-Modoki, which makes SWM failure.
      Note: To come with conclusion, its better to compare 2 similar type Elninos.

      1997 5 0.493308
      1997 6 1.01636
      1997 7 1.66241

      2002 5 -0.290515
      2002 6 -0.376617
      2002 7 0.230553

  7. Interesting facts, except 1957 & 1965, all years recorded +ve IOD (>0.5) with respect to ONI index (>0.5) by the SWM-onset.

    Overall 1957 stands as “special year” with Elnino & neutral IOD to be as “normal SWM-season”.

    There is other factor, which influencing SWM-rainfall apart from ONI & IOD indexes.
    There is other factor, which influencing SWM-rainfall apart from ONI & IOD indexes.

  8. OMG….among all strong-very strong Elnino years 1957, 1965, 1972, 1982, 1987 & 1997, only 1957 & 1997 recorded normal SWM-rainfalls. Remaining all years recorded below-normal/deficit SWM rainfall.

    Interesting facts, except 1957 & 1965, all years recorded +ve IOD (>0.5) with respect to ONI index (>0.5) by the SWM-onset.

    Overall 1957 stands as “special year” with strong-Elnino & neutral IOD to be as “normal SWM-season”.

    In conclusion:
    There is other X-factor, which influencing SWM-rainfall apart from ONI & IOD indexes.

  9. All other important parameters like SOI, QBO, PDO & AO analyzed in all strong-Elnino years 1957, 1965, 1972, 1982, 1987 & 1997.

    But there is no clear cut-correlation with QBO, PDO & AO.

    Interestingly its SOI only that makes 1957 as normal SWM-season despite strong Elnino with neutral IOD.

    Note: 1997 might have become normal SWM-year with “exceptionally very strong proportionally IOD-index with respect to ONI-index”, which is lacking in all other strong-Elnino years.

  10. How Rossby Waves Related to UAC.

    500 HPA winds are also called Upper Troposphere, around 5000 meters above sea level. In the
    upper troposphere, an average westerly flow, the upper air westerlies, is maintained poleward of
    about 15 to 20 degree latitude in both hemispheres. The upper air westerlies forms as a response
    to temperature difference between warm tropical air and cold polar air. The air in the equatorial latitudes is warmed, rises convectively to high altitudes, and then flows toward the polar regions.
    This is exactly opposite to surface air which moves from cold zone to warm zone.

    During the winter the temperature gradient between tropical and polar air is not uniform but concentrated where the warm tropical air meets cold polar air, This boundary, called the
    polar front, with its stronger pressure gradient, marks the location of the Polar Front Jet Stream.

    The upper air westerlies develop oscillations called Rossby Waves. These waves develop when Cold Polar Air pushes down the latitude forms Troughs of LOW Pressure’s and Warm Tropical Air Climbs above the Latitude forms High Pressure Ridges.

    The current oscillations over Bay of Bengal is due to Rossby Waves formation, if you see the jet stream at 500 HPA you will know that the cold air sinking across Odisha and down to West Central Bay, this is paving way for UAC to develop over East Central Bay where the Trough of LOW is created and move towards Tamil Nadu coast based on the upper level wind direction.

    The picture enclosed below shows how a Rossby Waves forming and influencing an UAC at 500 HPA levels. Also the latest ER wave map shows the convection increasing over Bay of Bengal.

    Picture A – Normal Flow of Jet Streams.
    Picture B – Rossby Waves form, Warm Air Raises in Latitude and Cold Air Sinks.
    Picture C – Trough and Ridge pressuring themselves by pushing each other.
    Picture D – Now formed HPA and LOW by cutting through and normal pattern will return like Picture A.

    Hope you all understood the concept of Rossby Waves, if not please ask me.

    UAC in Bay from May 26th to 31st 2015.

  11. Invest 92E over east-pacific ocean forecasted to become major-hurricane. Till that east-pacific hurricane weakens there won’t be any change in BOB-SWM front.

    East pacific hurricanes formation is the indication of the walker circulation more towards it (thus strengthening of Elnino). So descending limb of walker circulation will be over BOB & adjoining West-pacific.

    So high shear over BOB, which may weaken/progression of SWM-current.

    1) Very interesting fact is that east-pacific hurricanes “interlinked” with Arabian-systems through Elnino related walker-circulation.

    2) whenever there is as strong-system (hurricane cat.) over east-pacific, then Arabian will hoist weaker systems like Depressions/DDs.

    Whenever there is a weak system over east-pacific region, then Arabian ocean will set a stronger system (TS or above).

    The above analogy has >95% probability irrespective of ENSO-strength. This clearly indicates some important interlink between East-pacific & Arabian systems.

  12. One more interlink between Arabian & east-pacific tropical systems will be order of MJO propagation.

    MJO’s phase around date line (phase7, junction of phase 7 &8) enhances the chance of east-pacific system. Later when MJO enters phases 8 & 1 (next regular order), which enhances the Arabian-tropical system.

    Overall it looks East-pacific tropical system formation followed by Arabian system.

    The above explanation is so simple based on MJO-order of phases thus by avoiding deep explanation of Walker circulation’s ascending & descending limbs.


  13. 1957, 1965, 1972, 1982, 1987 & 1997 years are strong Elnino years with strong +ve IOD. But remaining other years, except 1997&1957, all other years recorded below normal SWM rainfall. do you know the correct reason why 1997 & 1957 have good SWM rainfall deviating from all other similar years???

    Answer to above question:
    I found answer after analyzing MJO, SOI, IOD, QBO, ONI, AO, PDO etc. parameters. one parameter is giving very nice answer why 1997 has become normal SWM-season. but people still not liking that parameter till today.

    Its none other than SOI. all other factors not correlating accurately. But SOI has good correlation.

    in 1957 during june & july (most crucial SWM-months) SOI styed at neutral range (+/-5).

    During 1997, SOI in active July month increased by 10 points (biggest gain after touching bottom in strong elnino-style). This might have made July a active SWM-month with support of +ve IOD.

    But in all years 1965, 1972, 1982 (despite +ve IOD), SOI factor in peak-July month either turned too negative than previous month June/no change/only slight increase (around 2 points). So deficit SWM-season despite +ve IOD.

    August & September contributes less when compared to June & July months.
    SOI-monthly index:

  14. at present 2 systems brewing over there. actually all tropical weather will come under same cycle that is “Hadley cycle” Pacific ocean related sub-circulation is “walker circulation”. which is directly related ENSO.

    active east-pacific hurricanes will do harm by 2 means.
    1. east-pacific hurricanes is indicative of Elnino-strength, so walker circulation will be more towards east-pacific.
    2. active east-pacific hurricanes means, regular elnino will become temporarily elnino-modoki (by the phenomenon of cooling Nino 1+2 SST relatively to nino 3.4 by removal of moisture over there)

    It is well documented in literature, Elnino-modoki will enhance system formation over Arabian than BOB. Reason is so simple: the descending limb of walker-circulation will be right-over west-pacific & adjoining BOB.

    application of above principle to present UAC:
    2 back to back east-pacific hurricanes means, Classical Elnino temporarily turned to non-classical Elnino-modoki. hence descending limb of walker circulation right-over BOB. Hence increase in Shear-value and sudden weakening od UAC.

    1. Consequences of pressure gradients are spontaneous when compared to consequences related to SST-gradient.
    2. Will try to explain based on MJO & SOI after receiving today’s BoM-SOI

  15. I was always saying that there is a difference between summer & winter ELNINO.
    We had 14 ELNINO years in the past since 1950, but only few of them were summer ELNINO’s.

    2015 ELNINO has been summer ELNINO. If ELNINO emerged in summer along with that Positive IOD, then we should get normal SWM. However IOD should become Positive before August, otherwise it will be too late.

    Summer ELNINO 1972, 1982, 1991, 1997, 2002, 2004, 2009 & 2015.

    1972 – Positive IOD developed before May. Deficit SWM
    1982 – Positive IOD. developed before May. Deficit SWM
    1991 – Positive IOD. developed before May. Below Normal SWM.
    1997 – Positive IOD in June. Excess SWM
    2002 – Positive IOD in August end. Deficit SWM
    2004 – Negative IOD. Deficit SWM. Conditions like 2014.
    2009 – Neutral IOD but ELNINO emerged late in August. Deficit

    Another factor is ENSO values can show positive and it will be declared ELNINO, but which part of Pacific has above normal SST, that has to be checked.

    Find the link below, how SWM had overcome 1997 ELNINO and how it failed in 2002. Even though you can say that Positive IOD developed on time in 1997 and was late in 2002, it was influenced by Pacific ENSO.

    Still Positive IOD has to emerge between May and July during Summer ELNINO years for successful SWM.

    Since West Pacific SST was near Normal in 1997, Positive IOD emerged. In 2002 West to East Pacific SST was above normal and East Pacific was hotter than West hence ELNINO formed, since West Pacific SST was above normal, Positive IOD could develop only by August. This is why SWM failed.

    This time in 2015, ELNINO declared in May, Positive IOD expected in a weeks time, SST over West Pacific cooling off.

    Almost everytime NW India is affected during ELNINO years, irrespective of Positive IOD, once again NW India might get affected.

    Central and NE India will survive, in some of the ELNINO years they got excess rainfall too.

    North and South India will be near normal this time. Except Tamilnadu, will surely face deficit.

    Hence SWM will succeed this year if strong Positive IOD emerges and the values keep increasing then this SWM will become a repeat of 1997, otherwise will fail again.

  16. Flash…QBOONI equation: We can get clear equation in Elnino/Lanina years. For example when QBO is in decreasing trend wrt ONI index’s increasing trend then either SWM/NEM will record less than normal. Likewise when QBO trend is in increasing order wrt ONI index’s decreasing order the either SWM/NEM will be less than normal.

  17. If we look at MJO-forecasted path (path A, meridional), it is losing intensity in IO-basin itself. This means it will be having more-off-equatorial path, which strengthens the Tropical easterly-Somali jets and hence good active SWM-conditions.

    If we look at MJO-drawn path (path B, zonal),without losing intensity at IO and enters WP. This means it will be having more-equatorial path, which weakens the Tropical easterly-Somali jets and hence poor SWM-conditions.

    1. MJO’s meridional path (S-N/SW-NE) will exhibit more wind alignment with SWM-winds. So it will create good coherence with similar angle in wind directions. So stronger SWM.
    2. MJO’s zonal path (complete W-E) will exhibit less wind alignment with SWM-winds. So it will create poor coherence with different angle in wind directions with SWM. So stronger SWM.
    3. Reasons for this variation in MJO as meridional in summer and zonal in winter due to difference in location of ITCZ.
    4. More number of MJO-travel in similar to path A will weaken Elnino-conditions.

  18. 2D-gyric map model for Arabian I-95A:
    Arabian system (I-95A) if sustains enough strength then it will cross the coast at SW-Pakistan at 65E,25.2N. If its a weaker system then it will move in similar direction and weaken in open waters of north-Arabian sea.

    Original latest satellite picture used for drawing 2D-gyric map model:

    2D-gyric map model:

  19. flash…..During 1997, just prior to active July month SOI increased by 10 points between mid June-JULY 1st (biggest gain after touching bottom in strong elnino-style in june-itself). This might have made July a active SWM-month with support of +ve IOD. So 1997 avoided severe drought.

    In 2015 SOI already increased by 10 points and forecasted to increase further. Also Elnino is in classical mode with +ve IOD. So we will see active SWM season in coming 30 days or beyond. This will turn the SWM-2015 deficit forecasts up side down 😄

    (1) in 1957 during June & July (most crucial SWM-months) SOI stayed at neutral range (+/-5). So normal SWM-rainfall.
    (2) But in all strong elnino years 1965, 1972, 1982, 1987 (despite +ve IOD), SOI factor just prior to active-July month either turned too negative than previous month June/no change/only slight increase (around 2 points). So deficit SWM-season despite +ve IOD.
    (3) Most importantly PDO index is in decreasing trend while ONI index (or Nino3.4 SST) unlike all strong Elnino years like 1957,1965,1972, 1982,1987 & 1997.

  20. to crack 1997-puzzle, which deviated from all other strong elnino drought years with +ve IOD, I have taken SOI-factor. I strongly believe moisture won’t come on its own without support of either SOI or IOD (which are only 2 trade wind effecting parameters till date I know in our IO basin). so either IOD or SOI must be of supportive especially when ONI-index increasing. Simply passage of equatorial waves doesn’t aid the convection to travel towards Indian peninsula without the support of IOD/SOI.

  21. Can we expect a super elnino (if not a strong elnino) with the cooling trend in eastern Pacific in the last week, while the Niño 4 region warmed slightly to 1.2 C.

    To our lucky still nino1+2>nino3.4 (a typical of classical elnino). but if we look at relative trend in SST, it looks pacific turned temporarily “elnino-modoki” pattern (as nino1+2 lost temperature by 1.7oC when compared to 0.1oC of Nino3.4, hence modoki-variation in classical mode).

    hence both east-pacific and Arabian oceans hosted tropical systems at the expense of unfortunately BOB is in inactive mode.

    Note: Weather-dynamics works on relative trend in abnormalities

    ————— Nino1+2——– Nino3 ——– Nino34 ——– Nino4
    29APR2015 —–26.8 1.9 —- 28.3 1.0 —- 28.8 1.0 —- 30.0 1.4
    06MAY2015 —-26.9 2.3 —– 28.4 1.2 —-28.8 1.0 —-29.9 1.2
    13MAY2015 —-26.4 2.1 —- 28.2 1.1 —-28.8 1.0 —- 29.8 1.1
    20MAY2015 —-26.6 2.6 —- 28.2 1.2 —-28.9 1.1 —-29.8 1.1
    27MAY2015 —-26.3 2.6 —-28.2 1.4 —- 29.0 1.3 —-29.9 1.1
    03JUN2015 —–25.3 1.9 —-28.1 1.4 —-29.0 1.2 —- 30.0 1.2

  22. I am thinking elnino-modoki variant doesn’t support NTN/SAP rainfall pattern (even relative modoki as subset in a classical elnino) . To crack this puzzle we need to run one more analysis with 1. Nino 1+2 SST, 2. Nino 3.4 SST, 3. difference between 2 SSTs 4. NTN/SAP rainfall centering Chennai.

    I think there will be 1 week time lag between SST-variation over nino region and precipitation reflects across Hadley cycle. need to find out.

  23. Can we crack “Bermuda triangle effect” puzzle for Chennai?? it looks so.

    I am thinking there will be 1 week time lag (or less than that), if we compare the east-pacific systems and present Arabian system timing wrt SST-variations.

    the week ending june 3rd starting from 27th may (where nino1+2 SST decreased when compared to nino 3.4 thus establishing elnino-modoki as sub-variant in classical elnino), has ignited series of east-pacific hurricanes, in the same time early in that week around May30-31, BOB-UAC (made first topic on disappointment note for Chennai) given all over heavy rains except around NTN/SAP centering Chennai.

    ————— Nino1+2——– Nino3 ——– Nino34 ——– Nino4
    20MAY2015 —-26.6 2.6 —- 28.2 1.2 —-28.9 1.1 —-29.8 1.1
    27MAY2015 —-26.3 2.6 —-28.2 1.4 —- 29.0 1.3 —-29.9 1.1
    03JUN2015 —–25.3 1.9 —-28.1 1.4 —-29.0 1.2 —- 30.0 1.2

    • I am thinking elnino-modoki variant doesn’t support NTN/SAP rainfall pattern (even relative modoki as subset in a classical elnino) . To crack this puzzle we need to run one more analysis with 1. Nino 1+2 SST, 2. Nino 3.4 SST, 3. difference between these SSTs 4. NTN/SAP rainfall centering Chennai.

      There will 1week (far from nino regions) or less time to 1week (closer to nino regions) lag with variation in nino SSTs with respect to tropical variations in Hadley cycle.

  24. why relative trend in anomalies of nino1+2 wrt nino3.4 is so important?
    then take hudhud-2014. by that time elnino-modoki established nicely. but due to increase in nino1+2 vs nino3.4 made temporary “relative classical elnino variant” in elnino-modoki conditions, which might have created favorable VWS conditions over BOB.

    one more example: try why Nilofer-2014 formed over Arabian (not moved towards BOB, despite origin at SE/E to SL)? if we compare both Nilofer and hudhud we can know this difference in relative anomalies
    1. ultimately both the pulses ignited by Kelvin+MJO
    2. There will 1week (far from nino regions) or less time to 1week (closer to nino regions) lag with variation in nino SSTs with respect to tropical variations in Hadley cycle.

  25. weakening ashobaa will move in W/NW or W/SW directions, so still 2D-map model working good with lack of intensity prediction.

    During Nilofer also this 2D-gyric map model worked good by indicating Gujarat LF, unfortunately its weakening taken away towards W/NW direction towards gulf of oman with no convection 😦

    this 2D-gyric map model shown excellent accuracy with 50KM error in LF south to vizag (might be due to human error in identifying the lines and drawings)

  26. IF a system moves without losing strength, then only we can believe in steering patterns. A weakening system always move in W/NW or W/SW directions. then how can anyone claim about steering pattern??

    I think if a system comes under the influence of steering ridges won’t lose strength and end abruptly in open waters 🙂

  27. I Always try to find the solutions in different way. I assume Elnino-Modoki won’t support any good rainfall activity for NTN/SAP centering chennai. So the Week ending on 7th June, nino1+2 SST cooled down when compared to nino 3.4, thus established “relative Elnino-Modoki” in a classical Elnino. This means that Hadley cycle which saturated with classical Elnino pattern turned Modoki-style. So chances for NTN/SAP diminished. This phenomenon existing since last 2 weeks. So Chennai not receving any wide-spread rains for the past few days and by considering time lag, even during next 1 week the same scenario may exist. Need to check this new observation in future rainfall events😄

  28. 2014 Elnino-Modoki is clear cut example of Elnino-Modoki with neutral IOD which completly dried SAP/NTN interms of seasonal rainfall. Note those rains over NTN/SAP might have occurred when nino1+2 SST increased over nino3.4 SST, thus establishing classical Elnino varaiation in Modoki-event

  29. Modoki sub-variant in classical Elnino
    . This means if you see last 2 weeks nino 1+2 cooled relatively with nino 3.4 (though still nino1+2 is warmer than nino3.4). This means Hadley cycle, which already saturated with classical Elnino style might turned to Elnino-Modoki sub-variant, thus setting poerful east-pacific hurricanes and arabian cyclone. The week ending june7th also indicative of similar pattern. This means next 1 week also hadley cycle will be in Modoki-sub arising. The forecasted rainfall events over arabian and eat-pacific clearly matching with this Modoki substyle.

  30. In 2014, starting from April-September (see figures 1 & 2, after initiation of historical high amplitude oceanic kelvin wave), MJO never attained good amplitude in WP-dateline to create any fresh WWB to reinforce the decaying EKW (though this doesn’t prevented warm Niño). So 2014 doesn’t turned to strong Elnino year (even not a Elnino year and stayed as Elnino-like year).

    Similar trend in MJO happening in 2015 also 😦

    Figure 1:
    Figure 2:

      • In 2015 also similar like conditions will exist if something drastic things doesn’t happen in near future (especially MJO has to enter WP-dateline in strong amplitude, nino3.4 SST indicator-PDO has to gain amplitude, nino 4.0 SST must cool down).

  31. Without knowing the cross section of our weather-cycles (Hadley-tropical, Ferrell-sub-tropical and polar cycle), we can never be “masters” in weather-dynamics. Please view 3D-cross section of our tropical Hadley cycle.

    So mostly during seasonal rains, our weather will be confined to our Hadley-cycles. any changes in weather-dynamics within our Hadley cycles are interlinked within short-time lags.

    Please don’t think that our earth (Hadley cycle) is so big, then there will be lot of time-lags. Please don’t forget that earth (Hadley cycle) is too big for us, but not for earth (Hadley cycle) itself 🙂

    3D-cross section of our weather cycles:

  32. 1) relative-increase in PDO during elnino and relative decrease in PDO during lanina.
    2) the probability of more number of Elnino years in warm phase of PDO is very high
    3) the probability of more number of lamina years during cold-phase of PDO is very high

  33. There will be time lag (expecting 3-7 days depend on the distance wrt to ENSO-effected area (area of walker-circulation) in Hadley cycle.

    As per my understanding Hadley cycle (other cycles) won’t start its dynamics freshly each and every day from 1. Entire weather is based on “anomalies”. Need to understand these anomalies also work in continuous form (without starting from 1 each day)

    For example:
    If we take Elnino-concept. Can a super elnino turn east-pacific SSTs very warmer relatively to west-pacific SSTs in (may be in future it may). I don’t think it has done in the past and may not in future too. So super-Elnino is the consequence of SST-anomalies. This means SEALED (leakages to Ferrell/polar via Ferrell) Hadley cycle (I don’t know when it started, might be millions of years ago when weather has formed) is changing its balance between Elnino and Lanina via walker circulation with only slight changes in SST-anomalies to effect the global-weather drastically.

    Weather dynamics are continuous (unstoppable at any point). This 3-7 days time lag is for sub-variations (not for whole ENSO)

    NOAA SSTs:
    NOAA SST anomalies:

  34. Title: Eastern Pacific tropical cyclones intensified by El Niño delivery of subsurface ocean heat

    reference: Nature, volume 516, Pages:82–85, 2014; DOI:doi:10.1038/nature13958 (published 04 December 2014)

    The El Niño Southern Oscillation (ENSO) creates strong variations in sea surface temperature in the eastern equatorial Pacific, leading to major climatic and societal impacts1, 2. In particular, ENSO influences the yearly variations of tropical cyclone (TC) activities in both the Pacific and Atlantic basins through atmospheric dynamical factors such as vertical wind shear and stability3, 4, 5, 6. Until recently, however, the direct ocean thermal control of ENSO on TCs has not been taken into consideration because of an apparent mismatch in both timing and location: ENSO peaks in winter and its surface warming occurs mostly along the Equator, a region without TC activity. Here we show that El Niño—the warm phase of an ENSO cycle—effectively discharges heat into the eastern North Pacific basin two to three seasons after its wintertime peak, leading to intensified TCs. This basin is characterized by abundant TC activity and is the second most active TC region in the world5, 6, 7. As a result of the time involved in ocean transport, El Niño’s equatorial subsurface ‘heat reservoir’, built up in boreal winter, appears in the eastern North Pacific several months later during peak TC season (boreal summer and autumn). By means of this delayed ocean transport mechanism, ENSO provides an additional heat supply favourable for the formation of strong hurricanes. This thermal control on intense TC variability has significant implications for seasonal predictions and long-term projections of TC activity over the eastern North Pacific.

    link: journal:

  35. Flash….

    Something wrong in the agencies prediction about strong-Elnino. They need to reassess their predictions regarding strong-Elnino (some even forecasting super-elnino).

    It looks all dynamical MJO-forecasts come in agreement with “loss in amplitude at MTC” and remerging towards Indian ocean/western hemisphere except ECMWF/BOM (these 2 also reduced the amplitude at MTC/WP to their initial forecasts).


    1) if the anticipated strong-Elnino doesn’t evolve then this event will turn Lanina-modoki (but relatively warm nino 1+2 SST compared to nino 3.4 SST but with warm nino index compared to 2005 pattern).

    2) So there is high chance for SWM to turn vigorous from Mid-late July again.

    3) This doesn’t prevent bumper NEM-2015 like 2005-style.


  36. very interesting question, which can give the correct answer for very repetitive doubt put forward by almost everyone.

    Suppose assume ONGC completed the new gas-pipe line (with valves arrangements to adjust the pressure) from Chennai to Vellore. As a first run ONGC released X cubic meters gas to Vellore through “new-vacant pipe line” Assume it has taken 1 day for reaching this 1X cc of gas to Vellore. But due to more demand, ONGC wanted to double the volume (by 2X cc) of gas-supply, through valve-adjustments. Then how much time it will take for reaching this 2X-cc of the gas to Vellore? will it be more than 1 day/1X cc or less than 1 day/per 1X cc?

    what is your answer?

  37. super….flash…

    (1) As everyone expecting SOI may not decrease sharply and stay permanently at -ve values. SOI will show frequent increase in values.
    (2) Moreover BOM revised that IOD to increase further to previous forecasts during July, august and September months.

    In conclusion:
    SWM will be in normal-excess mode during July, August and September months.

    1) After skymet, I am also too +ve regarding normal SWM prediction.
    2) This normal SWM rainfall doesn’t result in bad NEM. So no worries about NEM-2015 🙂

  38. Sriram, the examples of normal June rainfall with deficit SWM in Elnino years like 1991,2002, 2004 given by IMD looks rational. But we can remove 2002 & 2004 from the list to compare with 2015 phenomenon based on IOD itself. Both years had -ve IOD during May-JULY. So crucial month-july recorded (post JULY too) deficit rains in both 2002&2004. So 1991 only leftover to compare with 2015 based on normal June. But 1991 year, despite +ve IOD with neutral range SOI during SWM season, JULY (post JULY) recorded in deficit and hence SWM-season by -10.0 (not so big deficit). But this deficits also can be explained based on MJO behavior and unfavorable QBOONI (discovered by me). In 1991 during SWM MJO never entered indian ocean (even Western Hemisphere). Moreover most importantly QBOONI equation is unfavorable. Hence SWM-1991 ended in 10% deficits despite just normal June. However June-2015 going to end in 20% excess. Most importantly (if we keep IOD & SOI aside) QBOONI equation is highly favorable. Also expecting MJO will be entering Western Hemisphere frequently unlike 1991 episode. So SWM-2015 rainfall must end in normal mode (we will asses NEM-2015 by the end of September).

  39. during break-monsoon:
    the trough of LPA directly exist along foot-hills of Himalayas (over Gangetic plains near UP-Bihar-Jharkhand) in alignment with TN (Chennai)-longitude.

    Moreover under the absence of WP-typhoon, the SWM winds will be of no guidance, hence dump all of its moisture over S-Kerala, TN and Srilanka.

    So during break monsoon VS-TS in these areas will be intense. Due to presence of trough over same longitude with TN (Chennai) over SWM-axis, the definition of pure VS-TS fails.

  40. During major SWM-months (especially june & july, even till mid-august):

    First there should not be any Arabian system to give good VS-TS over Chennai/surroundings. If at all if there is system over Arabian it has to move into Indian mainland. Arabian system’s N/NE journey will enhance SWM-flow into interior TN, hence fast moving TS.

    can compare the difference between ashobaa & present Arabian DD

    • under absence of Arabian system, BOB-LPA might have moved far inland and could have oriented along same longitude with Chennai, thus could have reduced the SWM-winds.

      So on a sunny day with less SWM-speed, Chennai could have got wide-spread VS-TS (hybrid) with good quantum of rains.

      something is better than nothing, as Arabian system moving in N/NE direction to give at least these rains. At ashobaa time we even didn’t get single drop despite so many other favorable conditions 😦

  41. Flash….as SWM completing its grand marching till NW-India with bountiful rains (20% excess), I am expecting QBO might have increased (proportionally with ONI-index) further from present value of -12.0.

    June-QBO-value can be known in July 1st week.

    QBO forecast indicating westerly phase in coming months at least till September. This will enhance good SWM-spells in remaining SWM-season as against agencies’ forecast.

  42. Complete global dynamics especially ENSO-related can be explained by the heat transfer of “Pacific Oceanic kelvin wave (EKW)” through ‘ocean currents” along global conveyor belt mostly in 5 stages.

    Stage 1: Heat transfer to polar region, can induce arctic ice melt indirectly prior to Elnino dynamics peaks before spring.

    Stage 2: West-African Atlantic ocean SST (Elnino/Lanina-modoki exhibit abnormal cooling before northern hemisphere spring by May 31st/maximum June 30th).

    Stage 3a & 3b: Indian ocean’s tropical/subtropical IOD related pattern.(In a strong Elnino year stage3a becomes warm due to relative warm flow A, and stage 3b will become cool due to cut-off heat-from Nino region along with relative cool sub-flow B).

    Stage 4: Nino 4.0 exhibits cooling trend in a strong Elnino year.

    Stage 5: PDO exhibits relative warm trend in a strong Elnino year.

    2015 Elnino scenario:
    Stage 1 & 2 completed successfully. Stages 3,4 &5 are under progress to make 2015 as complete strong Elnino year.

    1. This complete NOVEL global dynamics’ explanation by Thermohaline-circulation is based on self-imaginary and may lack solid scientific proofs in the literature.
    2. Lanina dynamics may involve quite opposite dynamics to Elnino dynamics
    3. Thermohaline circulation-wiki:

    complete-global-dynamics related to ENSO through Thermohaline circulation:

  43. what is the speed of gulf stream? The Gulf Stream has an average speed of four miles per hour (6.4 kilometers per hour). It means 153.4 KM/day. 13806 KM/90 days (almost equal to distance between India & USA).

    1. The above speed is absolute speed. So relative speed still more rapid.
    2. If we take the speed of heat transfer (if we take conduction between neighboring water particles) will be still speeder
    3. So no need to have any doubts regarding heat-transfer originating from Equatorial ocean’s Kelvin wave (EKW) to the polar region and thus setting the global-dynamics in matter of months (not years as everyone thinking).

  44. Flash….Alert…Expecting SWM-2015 cumulative rainfall may exceed 1997’s average of 102%. I will come to final opinion for this excess SWM-rainfall to 1997’s after watching June’s real-time QBO value, which can be known by July 1st week.

    1. ONI index going to increase further.
    2. Already QBO is in increasing trend.
    3. According to SWM-QBOONI rule, under favorable rule SWM-dynamics including all parameters will orient to give normal-excess rainfall.
    4. Please not in kea-voting I had been more cautious to estimate SWM-rainfall around 93%, which is IMD’s 1st prediction.

  45. Flash…alert…WP super typhoon in the initial genesis stage (yellow circle) under the support of MJO.

    1. This super-typhoon will create wide-spread havoc along its path and can exactly mimics the super-typhoon Haiyan-2013’s path and destructive intensity.
    2. This particular super-typhoon will hold W/NW track below 10N till Philippines (little deviating from GFS- initial forecast). So Philippines might be on the red-zone.

    Special features:
    This super typhoon can ignite a powerful WWB, which will reinforce with east-pacific EKW and thus have the 100% flipping ability of walker circulation towards a strong Elnino.

  46. Predicting rainfall pattern with timing by Naked Eye Technology (NET):

    On a HIGH hot/warm and humid day in SWM season (can be known by morning itself, before noon 12:00 AM),

    1) If all level low, mid & high clouds (know the clouds’ type from wiki) present before noon, then by early evening/late afternoon itself there will be highest chance of wide-spread TS with good rainfall.

    2) If only mid-high clouds (know the clouds’ type from wiki) present before noon, then by late evening/early night itself there will be highest chance of wide-spread TS with good rainfall.

    3) If only high clouds (know the clouds’ type from wiki) present before noon, then by early late night/mid-night/early morning (rare during SWM) itself there will be highest chance of wide-spread TS with good rainfall.

    1) 6 more combinations can be derived from humid/hot levels in the order of MEDIUM and LOW with respect to cloud types/hence rainfall pattern.
    2) These NET points learned with experience by watching SWM-rainy days for years since childhood.
    3) One can become NEAR perfect by practicing NET carefully with broad vision to judge the correct combination among 9 probabilities for that day.

  47. Ehsan and Others,

    The reason is Westward Moving Planetary Wave which will move along equator and up to mid latitude mesosphere and lower thermosphere. This is nothing but westerly moving rossby wave. This is why the trough at mid levels dipping south.

    This one forms in West Pacific and extends upto Indian Ocean, this creates impact upto 15N latitude.

    From March to May which is the warming time of SST over Indian Ocean and West Pacific, so convection develops in both the areas, these 2 convection interact with each other some times, that is when the convection intensifies. This wave was in Maritime Continent until 25th and reached East Coast by yesterday as per the pic attached. Fine example of this wave extension towards Indian Ocean and up to mid latitudes, the 200 HPA winds have changed its direction to westwards over South Asia. This is why MJO has not emerged into Phase 2 or 3 as we were expecting few weeks back.

    As we were expecting that this MJO the eastward propagating wave will skip or weaken in Phase 5, but it had strengthened and moved through Phase 5 and now in Phase 6 as usual. The wind direction at 200 HPA levels has changed to Westward. since this wave has moved along.

    The below link shows that Westwards moving Negative OLR strong over SE Coast of India since yesterday, this is why we are getting TS today. In the northern summer, on the other hand, the amplitude of the westward-propagating waves is
    com-parable with that of the eastward-moving waves, and significant northward-propagating waves appear. Thus,
    the northern summer has more active transient waves and more complex wave patterns.

    Hence either Sea Breeze nor Break in Monsoon is not the reason. Please underline this statement.

    Finally my observation is successful.

  48. 2D-gyric map model track prediction by “DOUBLE vortex concept” (Figure 1):

    1. MOST PRECISE TRACK, drawn considering west-side vortex interaction and its merging with main-vortex of typhoon.

    2. So according to this track South-Korea will bore the brunt of this super-typhoon’s fury by its direct landfall.

    3. This south-Korean landfall predicted based on 2D-gyric map model to ECMWF’s which showed East-china or Japan Landfall in earlier runs.

    4. Unsymmetrical extrapolated innermost convergence line arising due to double vortex concept.

    5. DILF drawn by fixing the innermost divergence line as there is “no near by land like BOB.”

    Figure 1:

    2D-gyric map model track prediction by “SINGLE vortex concept” (Figure 2):
    1. LESS PRECISE TRACK (compared to above double vortex track), drawn WITHOUT considering west-side vortex interaction.

    2. So according to this track JAPAN will bore the brunt of this super-typhoon’s fury by its direct landfall.

    3. This Japan landfall predicted based on 2D-gyric map model to GFS’s which showed East-china Landfall in earlier runs.

    4. Symmetrical innermost convergence line due to single vortex concept.

    5. DILF drawn by fixing the innermost divergence line as there is “no near by land like BOB.”

    Figure 2:

    • Please don’t think that above diagrams’ are school children drawings. There is scientific gyric dynamics involved in the diagrams.

      Moreover this 2D-gyric map model completely depends on 2D-satllite pictures.

      No need any super computers to predict almost accurate-tracks well in advance when the system is at LPA/D/DD stages.

  49. I am not finding any reason for WP-typhoon NOT reaching super-status (cat.5). At the moment due to SW-Pacific (near NE Australia) cyclone’s peaking in intensity, this west-pacific typhoon not intensifying at faster rate.

    Once this Australian counterpart weakens, then WP-typhoon will intensify rapidly. Moreover SST & TCHP conditions are too conductive between 10N-25N (especially E/NE to Philippines/Taiwan). MJO already there with good amplitude to look-after any unfavorable condition arising at tropics.

    1. The reason you pointed may not do any harm for the system especially to attain cat.5 typhoon. Moreover west-pacific is not like BOB/Arabian basin to exhibit frequent -ve effect from arising from sub-tropics.

    2. The weakening for any typhoon/hurricane/cyclone after reaching sub-tropics is a common phenomenon. But this can not prevent the catastrophic effects rising from a devastating super-typhoons/hurricanes/cyclones. Moreover this sub-tropical -ve effect is very less in other 2 big oceans like Atlantic/pacific when compared to bay-like oceans like BOB/Arabian.


  50. TS confined to West of Chennai??

    Thing I found on why TS mostly not reaching Chennai or a weak one is reaching?

    Large cumulus and cumulonimbus requires an inflow of moist air in the lower levels. In fact,
    the sea breeze can provide the moisture to help form thunderstorm clouds.

    First on a cloudy day convection currents over the land (due to solar heating) are prevented
    or restricted. Thus the sea breeze circulation does not develop to any appreciable extent, and
    on many occasions of cloud cover will be non-existent.

    The location and amount of thunderstorms will vary depending on the overall weather pattern
    over the region. For example, the amount of sunshine and prevailing surface wind over the region has a large impact on sea breeze thunderstorms. If the wind is relatively calm then sea breeze can move well inland but with only scattered thunderstorms occurring about 1/3rd of the
    way across the region.

    2015 for example so far:
    The sea breeze front most of the time moving far interior means there was no lifting of warm
    air happening near the coast. The front move far interior and the sea breeze remains stronger
    near the coast, then the coastal belts will not get thunderstorms. It means that the lifting of air
    is happening inside the land and cumulus not moving towards coast or does not remain stronger while moving. Hence there is every chance that TS develops inside the land will weaken while
    reaching the coast.

    If the front stays near the coast or approx near to the Bermuda circle, then it seems that land
    breeze lifting above and cumulus or cumulonimbus will form. Once the cumulus or cumulonimbus formation begins this will push or weaken the sea breeze at lower levels and westerly winds will
    pick once again. Once this scenario happens, we can expect strong and widespread thunderstorms near the coast land.

    To Summarize:
    Finally, the sea breeze should not be too strong, hence it will not push the land breeze far
    inside, so the lifting happens far interior, hence the cumulus or cumulonimbus does not reach
    the coast.


    If even the TS forms in interior, the wind at upper level should become stronger enough to
    push cumulus towards coast, once this clouds near the coast the lower level sea breeze
    decreases its strength, so that the TS movement towards the coast is not disturbed.

    I hope that I have come closer to find out the reason for TS not entering the 30KM circle of Chennai.

  51. Flash….2D-gyric map model correction:

    If CHAN-HOM makes East-China landfall, then 2d-gyrci map model need to be corrected by considering 3rd vortex (intensified to typhoon LINFA) influence on CHAN-HOM.

    1. 2D-gyric map model faced problem in Arabian ocean due to closed basin 😦
    2. 2D-gyric map model facing problem at WP (may be in Atlantic) due to multiple vortexes? I will correct this later on when CHAN-HOM completed it journey.

  52. West-Pacific typhoon “CHAN-HOM’s” landfall prediction based on 2D-Gyric map model:

    1. If we consider single vortex (1st) to draw the 2D-gyric map model, which indicating SW-japan landfall (Figure 1)

    2. If we consider double vortex (1st & 2nd) to draw the 2D-gyric map model, which indicating South-Korea landfall (Figure 2)

    3. If we consider triple vortex (1st, 2nd & 3rd) to draw the 2D-gyric map model, which indicating Taiwan landfall. (Figure 3)

    It looks 3rd vortex intensified to typhoon Linfa (now forecasted to increase towards cat 1.) going to exhibit some influence on Chan-Homs’ final track. So now one more track based triple vortex-concept (Figure 3) can be drawn, which is indicative of Taiwan landfall.

    Under the absence of mid-latitude westerly trough and continuous intensification of CHNA-HOM, Taiwan-landfall may happen in contrast to GFS & ECMWF’s East-china Landfall. Need to wait and see whats’ really in store.

    Figure 1 based on single vortex:
    Figure 2 based on double vortex:
    Figure 3 based triple vortex:

  53. Flash….Core Chennai hybrid VS-TS rainfall alert….. between July18th-July 20th:

    Reason for rainfall:
    (1) As strong indications are evolving LPA/D formation along SWM-axis at higher latitude and its movement will be at the same longitude of Chennai between July 18th-20th. So there will be high chances of dry NW-winds to turn to moisture filled SW-winds between July 18th-20th. As a result of this SWM-axis oriented LPA pull effect, more moisture incursion from west-coast towards Core Chennai (30 km circle) will take place between 18th july and 20th july.

    (2) The intensity of these winds will be peaked on July 19th with the perfect alignment of this LPA with Chennai longitude, which could enhance the SWM-wind strength over Chennai due to pull effect.

    Rainfall quantity:
    Core Chennai will witness good wide-spread rainfall between 18th July and 20th July. The rainfall intensity will be peaked on 19th July. Most places will receive 10-30 mm rainfall if the LPA doesn’t intensify. If the LPA intensifies to depression then few places will receive more than 30 mm rainfall.

    Rainfall timing:
    Late afternoon to late-night.

    1st rain-spell:
    First spell might occur on Eid-al-Fitr evening (most probably on 18th July) between late afternoon and late night.

    This is my 3rd direct forecast (June 27-30 and July 8-13 are 2 previous successful forecasts) for core Chennai. Hope it will happen 🙂

  54. Guest11k,

    It looks SST gradient between spanning R1 & R2 playing crucial role in altering MJO & SOI behavior in accordance of IOD & ENSO. What’s your take?

  55. Both eqSOI (genesis area of SPCZ) ) and traditional SOI (middle of SPCZ) following similar pattern. Viewing SOI at different places is like watching a river at different places. For example river Ganges (main river) will be having same name entire track. Also flood situation will vary at different places depending on inflow from sub-rivers. Like that if any one asks me then I will prefer to make one more SOI (at the extreme southern tip of SPCZ), then to calculate average SOI of all these 3 SOIs (eq SOI + traditional SOI at middle of SPCZ + tail SOI that calculated at southern tip of SPCZ) to get cumulative SOI, which can give even clear picture about ENSO strength.

    • In actual sense MJO’s phase at 1&2 and 5&6 will provide good favorable wind pattern (Partha given nice wind pattern analysis in last year with respect to MJO phases) for TN & AP. But due to close to the equator TN grabs most of its advantage when compared to AP especially in SWM season. I will bring few past records of good systems that crossed at TN with MJO phases 1&2 and 5&6 later.

  56. all cycles Hadley, Ferrell & tropical are completely formed and saturated/balanced like “mechanical balance” over a millions of years in millions of years ago. Its only relative-variations in these cycles causing the weather dynamics (which human beings are monitoring in the form of indexes like MJO, SOI, SST, AO, NAO, IOD, AMO, PDO, etc.).

    Still human beings are unable to interlink 2 indexes that is ENSO & IOD in 100% till today. I can’t imagine how much time we can take to interlink all these indexes to understand the mother nature in absolute manner. Nature’s dynamics are continuous. so unless we interlink all these indexes we never ever understand it in 100% in future (we may need to take help of the GOD to establish complete interlink between these indexes in 100% to understand the mother nature n 100%) 🙂

  57. In Chennai itself it won’t rain in all similar pattern in a season, then how we are expecting “nationwide sub-divisional” cumulative index to be same with 100%??

    OK. Let the natural act be aside. We will discuss only one example (can discuss so many like this), which is in human hands. Lets take one class room filled with all intelligent students (with same IQ, no problem). Then can anyone try to make all students to get 100% marks in all subjects in regular exams (or in IIT-JEE/any entrance exam, etc).

    My answer for the above question is “simply highly impossible for all student to get 100% marks in all subjects (due to various factors)”.

    (1) Hope we all can understand the difficulty for our mother nature in giving 100% rainfall for all subdivisions in a single seasonal year (thank god as we didn’t expected all sub-divisional rainfall equally on each and everyday towards 100% rate).

    (2) IMD might have developed some formulae/process to calculate cumulative sub-divisional rainfall pattern based on law of averages. Even skymet (IMD) giving similar view about seasonal cumulative sub-divisional rainfall pattern (read the following article). Then why we have to blame IMD when even skymet supporting this uneven rainfall pattern??

    (3) Even human controlled biological in vitro or in vivo experiments will be made “the average of 3 experiments”. One has not to forget that “mother nature” is a biological system unlike a “computational-digital system 🙂

    (4) Still who doesn’t convinced with my argument then please try to calculate the average of all sub-divisional rainfall pattern in between “a Lanina & Elnino episodes (or at least 3 years average may also good)”.

  58. i used to say always that for better rainfall prospects either of SOI & IOD must increase. This hypothesis exactly proven in 2015. In June 2nd half both SOI ( drastic increase of 20 points till +3 from -17) & IOD increases to +ve so ultimately June ended with 16% excess. In July 2nd half only SOI increase (that too moderate from -20 to till -14 of 6 points) with no +ve IOD (instead decreased continuously). So ultimately July ended with -15% in deficit. This clearly proved the hypothesis of trade wind strength relatively on SOI & IOD parameters that effecting SWM rainfall pattern.

  59. WP-super typhoon SOUDELOR landfall at “Shanghai region” indicated by 2D-Gyric map model. This typhoon forming under single vortex scenario. So its track prediction by models will be very easier task.

    (1) Both GFS & ECMWF predicting Soudelor to make landfall at Fuzhou region.
    (2) If 2D-gyric map model fails wrt both GFS & ECMWF then 2D-model must be included with little correction to draw DILF, “by considering the entire complete divergence and convergence bands” instead of using innermost convergence and divergence lines alone.

  60. I have drawn small graph by taking ONI, QBO and SWM-cumulative rainfall in strong Elnino years. Its clearly evident that both 1957 & 1997 years have very favorable QBOONI equation and hence SWM-RF ended in normal/excess mode.

    SWM-2015 exhibiting similar trend of 1957 & 1997 with respect to QBO & ONI. So SWM-2015 definitely will end on normal mode at the end of September 30th, 2015.

    (1)QBO further increased to +7.45 from previous value of +2.18. As we already know that ONI is increasing trend due to strong Elnino conditions. So 2015 SWM will be having favorable QBOONI. So expecting good SWM-2015.
    (2) please note that ONI & QBO indexes are monthly during SWM-months, where as rainfall is cumulative SWM-RF

    graphical QBOONI-SWM-strong Elnino years.

  61. After seeing the real time track of WP-super typhoon Soudelor, I redrawn its track by considering the total influence of convergence and divergence bands. This new DILF drawn at the center point of between total convergence and divergence bands (green lines), from there final corrected track was drawn which closely matching with real time track.

    earlier track (figure 1) :

    corrected Sodelor’s track (figure 2) :

  62. As per my understanding “if moist surface winds travel to the top-most upper-level (blue colored, 100-250 mb level), then those winds shed all its moisture to form good convection to result in good rainfall events” (Figure 1). This indicates that the rainfall yielding dynamics (either monsoon/any tropical systems) are working in good health.

    For example:
    Good convection regions indicated in blue circles (Figure 2) having only upper-level 100-250 mb winds (blue colored) when compared to other upper-level winds (green/yellow).

    upper-level winds’ cross section (Figure 1):
    good convection regions (Figure 2):

  63. The following 2 upper-level winds diagrams (figures 1 & 2) indicate about the strengthening of SWM-dynamics today when compared to yesterday.
    Correction: upper-level winds direction will be in complete opposite direction to the lower level winds.

  64. Flash…deluge alert for Core Chennai between August 19th & 22nd: A very high intensity electric VS-TS (hybrid) may occur at many places of core Chennai between August 19th & 22nd (most probably around August 21st/22nd evening/night). Most places will cross 50 mm with 1 or 2 places crossing 100 mm mark. This electric TS can be more intense than August 4th TS that occurred at core chennai. Height of confidence based on: MJO’s close proximity at phase 2 (both by GFS & ECMWF) with perfect orientation of left side west Pacific typhoon (both by ECMWF & GFS) to pull the SWM winds hardly into southern tip of peninsular India.

    • 1st reason: MJO not come close to phase 2 as expected by both GFS & ECMWF earlier. 2nd reason: Goni weakens after nearing WP near Phillipines/Taiwan seas that too with recurving pattern (unlike its precedor W/NW tracked super typhoon Soudelor’s) 3rd reason: Now it’s UAC only when compared to August 4th Land based LPA. In conclusion based on the above 3 reasons, strong pulling of 850 HPA streamlines lacking over core-chennai when compared to august 4th/5th scenario.

  65. Flash..encouraging alert… Please don’t worry about present poor performance of rain-GOD over core-Chennai. MJO taken back seat only to bounce back at phase 2. So no worries as MJO will be entering phase 2 by this month End. When MJO entering phase 2, core Chennai doesn’t need support (like July last week non-stop rain Dhamaka) like either synoptic pulling form BOB/WP to strengthen 850 HPA streamlines. MJO:

  66. Flash…..july-2015 last week type continuous Chennai RF alert…. No need to disappoint about disappointed show a far below than expected due to MJO’s delayed entry at Phase 2 (Chennai’s RF hotspot). But it looks MJO re-boosting itself at phases 7/8, before entering comprehensively at phase 2 as per both GFS & ECMWF. So July-2015 last week type non-stop VS-TS event is in due. So stay focus on MJO’s movement today onwards. MJO-dynamical:

  67. Fresh Oceanic tropical convergence zone (OTCZ) was ignited by MJO+ER+KW+MRG. First time all equatorial waves are in action at IO to ignite much needed OTCZ. I never seen this type of active waves working all at same time in IO. One more interesting point is that new MISO-cell along ITCZ gets ignited over south-China sea, which will travel in W/NW direction to enter BOB. In combination of these dynamics, rainfall quantum over west-coast, peninsular and central India will increase many folds stating from September 1st week.

    Special VS-TS rainfall alert for core-Chennai:
    During this period Core-Chennai may witness violent VS-TS (In the order of august 4th, 2015 strength) more than once starting from September 1st week onwards . Good quantum of rainfall might be recorded at many places over Chennai.

  68. Flash…high intensity electric VS-TS (hybrid) for Core Chennai on September 3rd night (late night):
    A very high intensity electric VS-TS (hybrid) may occur at many places over core Chennai on September 3rd night (most probably from late night onwards). In most places RF will cross 50 mm within short time & with 1 or 2 places to receive RF close to 100 mm mark. This electric TS can be more intense than august 30th and close to August 4th TSs that occurred at core Chennai.

    Height of confidence based on:
    MJO’s close proximity at phase 1or 2 with ER at phase 2(both by GFS & ECMWF) with perfect orientation of trough line extension from CC around Orissa/WB/Jharkhand till TN with abundant moisture available at 700 hpa level on September 3rd.

  69. Flash..July last week type heavy rain alert for core Chennai….between 10th & 16th there will be continuous heavy TS formation over core Chennai more than 2 days just similar to July last week type event (but with less number of days unlike that July event). Core Chennai may get good amount of heavy rains during that period👍

  70. This is my own experience: Which gives strong support to “bullock-cart” principle. In weather dynamics it will be “gyric-bullock cart” principle.

    As per my own experience:
    I use earlier NCMWRF 850 hpa streamlines for knowing the direction of BOB-cyclones in advance. For example if a system forms with predominant E/NE 850 hpa streamlines, then I used to observe that cyclone to travel in W/NW direction. If a cyclone forms by predominant W/SW winds then I used to observe that cyclone to travel in N/NE direction. If a system forms with equal strength in E/NE & W/NW 850 hpa streamlines, then I used to observe that cyclone to travel perfect NW direction.

  71. Flash….Chapala alert….It looks MJO going to gain very surprising Intensity between September 14th & 20th at Indian Ocean. So during this time BOB can host the forecasted system, which has better chances to become “Chapala-Cyclone” (A cyclone in September month is very rarest phenomenon, a recent one is Pyarr-2005). Interestingly as per models’ earliest forecast, This Chapala-2015 may exactly follow the track of Pyarr-2005.

    If this forecasted Chapala-2015 forms and follows the expected track, then there will be very dangerous rains all along its track of AP, TS & MH states. So rivers Godavari, Krishna and Tungabhadra may receive one of the historical floods similar to 2009 (as these pre-Chapala rains going to saturate the soil over these AP, TS & MH states). Government agencies must take very early precautionary steps to prevent huge property and life loss.


    Pyarr-2005 & Chapala-2015 tracks:

  72. NEM onset this year will be between October 10-15, that too with a DD/Minimal cyclone crossing at NTN/SAP (centering Chennai). Rains will be pounded these regions between October 10&15, especially Chennai will be flooded👍

  73. Schematic representation (Figure 1) that why my September 3rd prediction failed (due to MJO’s reverse loop). Why the heavy rains started now with slight delay at Core Chennai (due to forward movement of MJO at phase 2).

    One can see the newly developing strong MISO under the effect of MJO +ER +MRG (Figure 2). This MISO will flood entire peninsular and central India with flooded rains in coming days. Especially Krishna and Godavari river catchment areas will receive exceptionally heavy floods.

    Figure 1: MJO at phase 2:
    Figure 2: MJO+ MISO:

  74. Flash….VS-TS hybrid alert over core Chennai on September 11th & 12th….due to combination of MJO at phase 2 with BOB-synoptic pulling/formation effect, there is high probability for Core Chennai to receive wide-spread VS-TS on 11th & 12 th. Most places may receive 50 mm rainfall. One or two places may receive more than 50 mm. So be on high alert for next 2 days👍👍👍

  75. Flash…alert…there is good chance for wide-spread TS (hybrid due to Vamco) between September 20th and 22nd at core-chennai. Many places might receive 30-50 mm heavy rains. Note: I decreased the quantum of rains due to recent failures.

  76. Flash..alert…blind synoptic formula for Core-Chennai…I said 1000 times this. Please let me brush-up its again. When the following formula going to happen, then no need to see other factors like NET/NBT parameters.

    Chennai-synoptic VS-TS success formula:
    Whenever a synoptic CC stays at between junction of Jharkhand/Orissa/WB (East-central India) and MP (central India), then there will be high chances for Core-Chennai to receive good quantum of rains.

    Recent examples (happens without MJO’s presence at hot-Phase 2):
    (1) Komen has given a catastrophic hybrid-VS-TS on august 4th recently.
    (2) Now Vamco going to give almost such intensity rains.

    my earlier forecast:

    850 hpa:,17.49,1205

  77. As usual NE-curved WP-typhoons, models started confusing. GFS is somewhat better when compared to ECMWF in foreseeing the future track of Dujuan.

    Dujuan’s track based on 2D-map model:
    It looks Dujuan will be encountering mid-latitude upper-level trough (indicated as yellow lines) after it comes close to E/NE of Taiwan. Due to this interaction Dujuan will take very sharp E.NE track, which will brush off entire Japan. This 2D-gyric map model track (indicated in white line) is in good agreement with GFS track.

    Unfortunately ECMWF, JTWS, CIMSS will miss their forecast very badly. GFS may emerge as sloe winner.Time will reveal the real track.

    Dujuan’s 2D-gyric map model:

  78. Flash…alert for Nunga/Meena (core Chennai violent TS alert) between 26th & 29th (especially on 27th/28th September)……..No need to worry about missing wide-spread rains for Nunga/Meena in September. But slowly few important parameters turning rain friendly for Core-Chennai from September 26th onwards.

    Especially on September 27th/28th, all must be on high alert due to possibility of violent electric thunderous wide-spread VS-TS that arriving from N/NW. Most places my cross 50 mm within no time. 1 or 2 places may even cross 100 mm. So be careful 🙂

  79. I (with all acceptance) would like to introduce impact factor (in general this IF terminology will be used in estimating the quality of scientific journals) in our bloggers’ comments impact. Nature journal has 41.456 impact factor (highest among all scientific journals). Science journal has 33.611 impact factor. I don’t have idea how they calculate this IF value.

    nature IF:
    science IF:

    so the formula for our blogger impact factor:
    number of likes/number of comments made. The higher the impact factor (IF) then higher will be the influence made by that particular blogger among readers.

    1. Any suggestions will be most welcome to calculate this IF value of the blogger.
    2. hope this introduction of IF of blogger will enhance the quality of the comments to get more likes (hope there won’t be any biased likes to improve their IF value) with good contended comments. hence the quality of blog automatically gets elevated.
    3. this IF will be added to bloggers’ profile page by the administrators.

    For example if we calculate my impact factor:
    I made 25441 comments and received 19795 likes.
    therefore my impact factor will be 19795/25441= 0.778

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