With wind pattern changing to South West, Rains are expected in Chennai

For the past one week, the wind pattern in Chennai was blowing from east, which means storms have to come from Sea, which is climatologically not possible unless you have strong LPA or Depression near Chennai Coast, which will become one of rarest of rare event. After lot of hopes, storms dissipated every-time storm reaches close to Chennai from sea.

Now the wind pattern has been restored to its natural course with good moisture carrying winds at all levels (500-850 hpa). In addition to this, the trough line from the upper level circulation extends to Chennai latitude. If we are going to get rains for balance part of August, nothing looks better than today.

Note: The above summary is based on the Charts of 12 UTC of 23-08-2014.

684 thoughts on “With wind pattern changing to South West, Rains are expected in Chennai

  1. With the recovery of three more bodies from under the massive landslide debris at Malin village near here, the death toll in the calamity has climbed to 109, even as the NDRF(National Disaster Response Force) operation to locate possible survivors entered the sixth day on Monday amid intermittent showers. The Geological Survey of India (GSI) has issued a advice to rescue team and district officials to evacuate remaining houses near the landslide site.

    “If it continues to rain for another 3-4 days, there is a possibility of further sliding in the adjacent portions of the landslide that has already taken place,” a statement issued by the GSI said. The 109 dead included 44 men, 49 women and 16 children, district administration officials said. Carcasses of 22 animals too have been extricated from the mound.PTI

  2. Japan gears up for Typhoon Nakri
    “Very heavy rain is expected to fall in western Japan, mainly on the island of Shikoku, until Tuesday noon,” the Japan Meteorological Agency said.

  3. Evacuees desert relief camps in BiharVishwanath Inter College in Bhaptiyahi on the outskirts of the Supaul district headquarters is bursting at the seams, on paper. The college has been turned into a relief camp for evacuees who live within the embankments of river Kosi. It has 1,200 people on its roster, but less than 60 are to be found.

  4. Woman drowns in swollen stream, youth goes missing in river

    Two shutters of the Banasura Sagar dam in Wayanad were opened by 50 cm on Monday morning after the water level in the reservoir crossed the danger mark of 775.5 metres; and a flooded rice field at Kannannur in Palakkad
    Ernakulam suffers heavy loss in rain
    Minister blames rain for potholes on roads
    Officials designated to attend to waterlogging

  5. Conservation drones for Nilgiri tahr count
    The Wildlife Institute of India, Dehradun, is drawing up a plan to introduce the unmanned aircraft for population estimation and tracking the movement of the endangered mountain goats. The drones will be equipped with high-resolution mapping cameras that can click pictures for a pre-set period. The images can be stitched to obtain a picture series of the animals, K. Ramesh, scientist at the institute, said.

  6. Pradeep, kindly post the cumulative figures of important cities of India from June 1st till Now..Weekly twice if possible post the cumulative figures.

  7. Kolkata experienced a wet and windy Sunday while the sun played hide and seek with the clouds on Monday. With the Regional Meteorological Centre, Alipore, predicting a similar weather for the next 24 hours, Kolkata and its adjoining areas are likely to receive heavy rain. According to the regional weather department’s official website, an upper cyclonic circulation was lying over the Bay of Bengal, extending between 5.8 and 9.5 km over the sea level.

    The cyclonic formation over the Bay of Bengal and its surrounding areas is moving towards central India. Due to this, many of the sub-divisions in central and western India received excessive rain over the past week.

  8. Idukki district gets super rains, Keral rainfall ending 8.30 am on 04.08.2014
    The offshore trough at mean sea level from south Gujarat coast to Kerala coast persists.

    in mm (min 40 mm)

    Peermade – 165
    Piravom – 149
    Pambla – 147
    Neeriyamangalam – 119
    Lower Sholayar – 108
    Perumbavur – 101
    Idukki – 99
    Vazhathope – 98
    Parumbikulam – 93
    Munnar – 86
    Sengulam – 83
    Kochi CIAL – 81
    Kakki – 78
    Thodupuzha – 76
    Chalakudy – 76
    Kozha – 74
    Kottayam – 70
    Idamalayar – 68
    Kurudamannil – 65
    Madupattey – 62
    Vyttiri – 60
    Poringal – 60
    Kanjirappally – 58
    Pamba – 57
    Myladumpara – 57
    Alwaye – 57
    Kochi AP – 57
    Irinjalakuda – 56
    Kuttiyadi – 55
    Ernakulam South – 51
    Hosdurg – 50
    Perinthalamanna – 48
    Mattanur – 47
    Pattambi – 45
    Karipur AP – 44
    Alathur – 44
    Aryankavu – 42
    Vadakara – 41
    Iikkur – 41
    Angadipuram – 41
    Konni – 40
    Kodungallur – 40
    Thrissur – 40
    Cherthala – 40
    Manantoddy – 40

  9. Courtesy: Accu Weather

    While the United States will escape a direct hit from Hurricane Bertha, increased surf and the threat of rip currents will still develop along the East Coast this week. On Monday, an aircraft investigating Bertha detected hurricane force winds. This week, Bertha will turn northeastward into the open waters of the Atlantic Ocean and will stay away from the United States. Showers and thunderstorms affecting the southern Atlantic coast on Monday were not associated directly with Bertha, but rather an old frontal zone and a non-tropical disturbance.That does not mean that the beaches of the U.S. East Coast will escape impacts from the bypassing tropical storm.

  10. Why do Oceans and Rivers Suddenly Change colors?

    Weather and other factors may play roles in why mysterious changes in color, sometimes overnight, occur on oceans, rivers and other waterways. A Chinese river changed colors overnight in mid-July, prompting a government investigation into why the river in Wenzhou turned blood red. Government officials said there was no sign of environmental pollution from nearby factories,the Voice of America reported. However, they didn’t rule out environmental pollution as the reason for the sudden color change, according to the China News website.


    • ITCZ’s line of action very much visible, and Halong’s long reluctance to move quicker is also evident with those bright colors to the east of Philippines ……..

  11. Valparai – 80.2 mm. What will be Chinnakallar total rainfall today. It has got 750 mm in last 5 days.

  12. imd report :
    Cumulative Rainfall: Total rainfall during the past 24 hours reported by 404 stations in the plains is 450.9 cms. Normal for these 404 stations is 433.2 cms.

  13. Madden-Julian Oscillation over western tropical Indian Ocean

    The Madden-Julian Oscillation (MJO) remains weak and is moving slowly eastwards over the tropical western hemisphere. Wind and cloud patterns indicate the MJO is probably located over the far western Indian Ocean, but may not be a strong influence on current tropical weather.

    Most models forecast the MJO to maintain a weak influence over the tropical Indian Ocean for the coming week. When the MJO is over the Indian Ocean at this time of year, stronger-than-normal easterly winds are usually present over northern Australia.

    Based on the location of the MJO, the northwest Pacific Ocean would typically be under suppressed conditions; however, typhoon along (Jose) is active over the west Pacific and is tracking north, toward southern Japan. As evidenced by typhoon Halong (Jose), it is important to remember that cyclonic activity is still possible even when the broad scale MJO set up may discourage it. Sea surface temperatures in the western Pacific Ocean are in excess of 28 °C and large-scale tropical convergence is present across South East Asia and the central Pacific Ocean. While tropical cyclones can form over the northwest Pacific at any time, the typical tropical cyclone season runs from May through November with peak activity in August. Hence, the risk of tropical cyclone development across the Pacific Ocean remains heightened for the coming month regardless of the strength and location of the MJO.


  14. Precipitation all over India may come down slowly in the next 48 hours.
    The next spell would start by 10th or 11th as per indications.
    MJO may not be strong as expected, but it will also not disturb the flow of SWM over India.
    When MJO enters Phase 3 by 10th or 11th, this should trigger more westerly winds, once again SWM will rejuvenate and then we will get more rain by that time.

    Hence MJO in Phase 2 is expected to suppress rains all over India.

    Chennai and TN may also need to wait till 10th.

  15. ENSO state: neutral
    Across the equatorial Pacific Ocean, the latest NINO3.4 sea surface temperature anomaly is at +0.2 °C. The latest official Southern Oscillation Index (SOI) value for the month of July is −3 and the average SOI over the last three months is nearly zero. While the chance of an El Niño in 2014 has clearly eased, warmer-than-average waters persist in parts of the tropical Pacific Ocean, and the (slight) majority of climate models suggest El Niño remains likely later this year. Hence the establishment of El Niño before year’s end cannot be ruled out. If an El Niño were to occur, it is increasingly unlikely to be a strong event.

    • If ENSO and IOD neutral before NEM then we should wait till 2015.
      NEM will be a big failure this year too.

      If IOD is negative, it has to remain negative till NEM onset.

      • yes, i would say atleast till first week of October.
        if both becomes neutral, then gone.
        if IOD becomes neutral before October, then at least ELNINO should emerge strong, this will take care of NEM.

      • I have my doubts in ElNino this year, the iod being negative as of now is the only card available for us, so it’s a gamble which we will have to live with.

  16. Crops destroyed, houses damaged in Idukki

    The continuing rain wreaked havoc in Idukki district on Monday, completely damaging a house in Udumbanchola taluk and partially damaging another one at Erattayar. Earth caved in on a two-storeyed building under construction at Adimaly early on Monday. A major accident was averted as the workers had not reached the spot when the earth caved in around 6.30 a.m., said the Adimaly police The entire building was affected with pillars falling down. http://www.thehindu.com/todays-paper/tp-national/tp-kerala/crops-destroyed-houses-damaged-in-idukki/article6282414.ece

  17. Rain causes crop loss of over Rs. 27 crore in Alappuzha

    The heavy rain witnessed in the district during the past few days has resulted in widespread agricultural losses.The district administration has pegged the total loss of crops, including paddy, to be worth Rs. 27.54 crore. Farmers also suffered losses worth Rs. 35,000 due to cattle deaths. http://www.thehindu.com/todays-paper/tp-national/tp-kerala/rain-causes-crop-loss-of-over-rs-27-crore-in-alappuzha/article6282415.ece

  18. Siruvani Dam continues to overflow

    For the third consecutive day on Monday, water continued to overflow from the Siruvani Dam, one of the three important drinking water sources for the city. According to sources in the Tamil Nadu Water Supply and Drainage Board, the water level at the dam stood at 50.32ft, more than a foot over the full reservoir level of 49.54ft. http://www.thehindu.com/todays-paper/tp-national/tp-tamilnadu/siruvani-dam-continues-to-overflow/article6282109.ece

  19. Precipitation all over India may come down slowly in the next 48 hours.
    The next spell would start by 10th or 11th as per indications.
    MJO may not be strong as expected, but it will also not disturb the flow of SWM over India.
    When MJO enters Phase 3 by 10th or 11th, this should trigger more westerly winds, once again SWM will rejuvenate and then we will get more rain by that time.

    Hence MJO in Phase 2 is expected to suppress rains all over India.

    Chennai and TN may also need to wait till 10th.


  20. Water logging spreads panic in Cuttack
    While the two rivers—Mahanadi and Kathajodi surrounding Cuttack city on three sides are in full spate, the perennial water logging problem of the city has multiplied. With three days of continuous rains, vast stretches of low-lying areas of the city are reeling under water logging and the situation is unlikely to improve for next few days when more rains are predicted. “Since both the rivers surrounding the city are flooded, accumulated rainwater cannot be cleared even using the pumps”, said a city civic body official overseeing the deployment of water pumps. Over hundred pumps are now pressed into operation across the city to remove the water logging.


  21. Water-level in Bhadra Reservoir in Shimoga district has reached 183 feet on Monday against full reservoir level of 186 feet, owing to copious rain. The water is to be discharged from the reservoir at the rate of 30,000 cusec from 4 p.m. today. People in low-lying areas along the downstream of the dam asked to move to safer places.

  22. Bridges, road closed
    The bypass road at Puttur remained closed on Monday due to stagnation of rainwater on the road. The low-lying bridges at Hosmatha in Puttur taluk and at Kukke Subrahmanya in Sullia taluk were closed for traffic late in the evening on Monday as they submerged due to heavy rain. Belthangady recorded 81 mm rainfall in 24 hours ending at 8 a.m. on Monday. Puttur recorded 62.2 mm, Kadaba 50.2 mm, Bantwal 41.1 mm, Moodbidri 39.2 mm, Mangalore 22.2 mm and Sullia 19.2 mm, during the period.

    • As per BOM latest update “The latest IOD index is −0.7 °C. All dynamical models surveyed by the Bureau of Meteorology forecast the negative IOD pattern to dissipate within the next month or so”.

  23. IMD
    The Deep Depression over Jharkhand and adjoining Gangetic West Bengal has
    moved westward and lay centered at 0530 hours IST of today the 05th August 2014
    over north Chhattisgarh and adjoining Jharkhand and northwest Odisha, about 100 km
    east­ southeast of Ambikapur. The system would move nearly westward direction
    during next 24 hours.

  24. As per BOM “the latest IOD index is −0.7 °C. All dynamical models surveyed by the Bureau of Meteorology forecast the negative IOD pattern to dissipate within the next month or so”.

  25. Low-lying areas in Kottayam district flooded; highland faces landslips
    School, three houses damaged in rain
    112 people moved to relief camps

  26. Like yesterday the window for rains is small today as well, between 5 and 8 PM when there is good support available at 700 and 500 HPA levels.

    Yesterday I was sure there was no rains I don’t see much hope today either, the chances are lesser than 50:50.

  27. Top 10 dams of India.
    Cheruthoni Dam is the biggest one, it is from Kerala’s Idukki District, constructed on Cheruthoni River. It is 450 feet height and 2300 feet length.

    2 dams featured from TN. Mettur and Bhavanisagar from Erode.

    Mettur dam is 04th biggest with 120 feet height and 1700 metres length.
    Bhavanisagar 10th biggest with 105 feet height and 1700 metres length.


  28. El Nino and La Nina

    El Nino and La Nina events tend to develop during the period Apr-Jun and they
    tend to reach their maximum strength during Dec-Feb.
    Typically persist for 9-12 months, though occasionally persisting for up to 2 years.
    Typically recur every 2 to 7 years.

  29. Guys..look outside immediately…strange cloud shape formation over city…visible NE of Porur…check it out..butterfly shaped medium level cloud..

  30. That 13 is a lucky number for Central and North Madras and unlucky for South..That has been the case last few weeks..

  31. Even in close range one will need a magnifying glass to identify these popups, let’s see how they develop

    • Think we can look beyond the local conditions in case of TS..Where it originates is the key. It may or may not be cloudy, still we can expect something from areas like Nagari, TPT where it may be very hot.

  32. Mahabaleshwar 31cm….
    Departure 421 mm excess….
    What a run it had from deficit of around 700mm to excess of 421 mm in just 20 days…

    More rains on the way to the region as the DD is expected to move west-North west…

      • But our TN interiors are facing drought like situation… At least the Southern distrcits had a good Pre-monsoon rains, but northern districts are facing huge deficit this SWM. No big rains reported in Kgiri, vellore,TVM, villupuram, cuddalore, Salem, dhramapuri, Kanchi dists for the past 2 months..

      • Ganesh. SWM is for every other state except TN to a large extent..That has been the case for a long time..Only TS are saving grace for us…I mentioned about areas other than TN.

      • I was discussing this with sri the other day, its strange that TS are not forming in KG and vellore district..

        We see storms forming from Gudiyatham and Vellore and moving towards chennai.

        This July its absent completely.

      • not only those areas, the areas in AP & TS states, except drizzles.

        Very active convection developing in SW-SC BOB from next week onwards. Hope those leftover areas will receive heavy rains during this period.

        Expecting MJO at Indian ocean will do miracle this time for the remaining rain-deficit areas in TN, KTK, AP, TS & MH states.

        At the same time IOD index has to become little positive value than present value, so that that convection will travel towards southern states.

      • Pradeep, its just a matter of time to see those areas you mentioned ..I will not be surprised if it does not start forming in those areas sooner or later…

      • Like the “langote” there used to be stream of water that used to flow always. for the last 3 years thats also evaporated. “No rains for 3 yrs” – farmers refrain

    • Even before butter melts Pennai floods goes the saying, though I have seen it overflow quite a few times, the frequency has been coming down

  33. Friends,

    Not only the areas in NTN, the areas in AP & TS states (especially central-southern parts) also did not receive any heavy rains except drizzles.

    Very active convection developing in SW-SC-WC BOB from next week onwards. Hope those leftover areas will receive heavy rains during this period.

    Expecting MJO at Indian ocean will do miracle this time for the remaining rain-deficit areas in TN, KTK, AP, TS & MH states.

    At the same time IOD index has to become little positive value than present value, so that that convection will travel towards southern states. Otherwise this convection lose all its steam in BOB itself.

      • present value around -0.7. Expecting IOD to become little positive i.e. around at least -0.6 (instead of -0.8). So that the active convection will enter southern states.

        reason is that dynamics are SWM, increase in IOD will help SWM-condensation towards sub-continent contrary to NEM-dynamics.

        Otherwise 2013’s Lehar story will repeat, I.e. this convection lose all its steam in BOB itself.

  34. Friends,

    I had seen south pennar flowing above the danger mark in 2011, when i visited in train to Kumbakonam.

    The water was almost touching the railway bridge.

    Also could see the floods in Colledam while traveling on the same day.

    That time it was pouring in south TN, when came back to Chennai after crossing Villupuram, nothing, it is totally dry.

  35. POAMA latest forecast came out yesterday and its showing neutral iod in NEM season and neutral( la nada) conditions in EP.

    [ this model is performing well from past two years. It correctly predicted 2012 will not be el nino, and it also correctly predicted neutral condition in M,J, J when every other model were predicting strong el nino beginning from May. I think we should give some attention to this model]


    • no need to worry about this neutral values with negative shade. NEM will be excess this yr, unlike 2012 & 2013.

      Main reason very abnormal warm SST near Alaska & California NE-pacific coasts at present till september (before NEM-onset) will give excess NEM-rains.

      • As per latest BOM update ” The latest IOD index is −0.7 °C. All dynamical models surveyed by the Bureau of Meteorology forecast the negative IOD pattern to dissipate within the next month or so.”
        Negative iod will dissipate by august end, so during NEM season we will be left with neutral iod and la nada condition which is not a good sign for NEM. It should be either negative iod with neutral( la nada) or neutral iod with warm nino 3 region sst for good NEM season.

      • But the warm SST around NE-pacific ocean near Alaska & California coasts prior to NEM-season will do miracle this season even if IOD & ENSO return to normal.

      • Yes, you’re right. 2012 was neutral iod and la nada but it had cool sst around NE pacific, that’s why NEM failed. This time we have warm SST around NE pacific which should help in bringing good NEM season.

  36. Rami,

    No problem with Negative IOD so far.

    It bought rain in most part of the country and many places flooded.

    As far as Chennai is concerned it has received normal to excess rainfall so far.

    Many places in TN is still getting good rain, especially the foot hills of western ghats.

    Lets wait and see how things progresses.

  37. When was the last time someone saw at least stream in Palar ????

    @Kea , Can answer this, as a native of Ambur…

    • As a native of North Arcot, in all my years, ive seen water flow in Palar only 2 or 3 times till now..I don;t even remember when i last saw water flow there. All i remember is the flow once or twice when i used to travel by bus from Katpadi Township , Gandhi Nagar,till Sainathapuram, Vellore during my school days..Must be November month.

    • I have seen Palar flood a few times as well, including somewhere around 2009 if my memory is correct .

      Pre 2000 I have seen it flow right up to the road bridge in Chengalpet

      • I have seen water flow in Palar even near Kalpakkam, the point where it meets the sea

      • Used for off roading now a days – Palar Challenge. Organizers claim it to be the toughest in India.
        Challenging it to carry water would be even more challenging

      • Palar challenge, the Holy grail for of roaders used to know a few guys who were part of it.

  38. IMD Evening Update

    The Deep Depression over north Chhattisgarh and adjoining Jharkhand & Odisha
    moved west­ northwestwards during past 06 hours, weakened into a depression and lay
    centered at 1430 hours IST of today the 05th August 2014, over north Chhattisgarh and
    adjoining east Madhya Pradesh, about 150 km east of Umaria. The system would move
    in west ­northwesterly direction during next 24 hours and weaken gradually further

    • You are looking everywhere except Siberian high directly effecting sub-tropical pacific ocean index (SPOD).

      The warm SST anomalies prior NEM-season around NE-pacific near Alaska & California coasts will give excess NEM-rains even though IOD & ENSO turn neutral in 2014.

      • Would it mean the SST anomalies near Siberia play a far greater role than ENSO and IOD for NEM

      • the index between west subtropical & east subtropical pacific ocean (till prior NEM-onset) has full dominance than all other factors, which is directly effecting NEM-winds via Siberian high.

  39. Rami,

    Global surface temperature in relation to northeast monsoon rainfall over Tamil Nadu

    The local and tele-connective association between Northeast Monsoon Rainfall (NEMR) over Tamil Nadu and global Surface Temperature Anomalies (STA) is examined using the monthly gridded STA data for the period 1901–2004. Various geographical regions which have significant teleconnective signals associated with NEMR are identified. During excess (deficient) NEMR years, it is observed that the meridional gradient in surface air temperature anomalies between Europe and north Africa, in the month of September is directed from the subtropics (higher latitudes) to higher latitudes (subtropics). It is also observed that North Atlantic Oscillation (NAO) during September influences the surface air temperature distribution over north Africa and Europe. Also, the NAO index in January shows significant inverse relationship with NEMR since recent times. The central and eastern equatorial Pacific oceanic regions have significant and consistent positive correlation with NEMR while the western equatorial region has significant negative correlation with NEMR. A zonal temperature anomaly gradient index (ZTAGI) defined between eastern equatorial Pacific and western equatorial Pacific shows stable significant inverse relationship with NEMR

      • There is no clear cut cause and effect relationship in my opinion

        Each study focuses one part while ignoring the others.

      • Everything is studied except the warm SST anomalies near Alaska & California coasts over NE-pacific till at least September interlinking with NEM.

        This is novel concept I think.

    • North Atlantic oscillation index (NAO) and arctic oscillation index (AO) inversely related with NEM-rains.
      The relation between subtropical pacific ocean index (SPOD) wrt to SWM is published in 2014. But its relation wrt NEM not reported in the literature.

  40. @guest11k:disqus

    Do conditions again turning not favourable for NEM ?

    In your below comment the news does not look good .
    what does that mean ?

  41. For those who wanted to know when palar was last flooded, manage to take my memory and get the answer, November 2008 just after Cyclone Nisha

Please restrict Comments to Weather only

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s