Rains loom large over coastal TN

The Upper air circulation (UAC) in South west Bay of Bengal and neighborhood persists. Under its influence, a Low Pressure Area (LPA) is likely to form and expected to move towards Tamilnadu Coast in the coming days.
Interior Tamilnadu will get some thunderstorm today as well, with increase in rainfall for coastal areas of TN. Depression over Arabian Sea becomes a named system as “Cyclone Megh” and it is expected to move towards Yemen again.
Chennai – Ideal conditions for moderate to heavy showers in Isolated Places . Beautiful Cumulus formation to occur during day break. Robust winds are likely. Maximum Temperature would be around 32c.
Vellore – Chill morning expected and with some rains in evening. Maximum temperature would be around 31-32 C.
Madurai – Day Temperature will hover around 31-32C. Thunderstorm formation likely in the area.
Tiruchirappalli – Chances of few spells of moderate rains. Temperature will be around 32c.
Coimbatore – Day time will remain cloudy. Breezy conditions during the day. One or two spells of rain at isolated places. Mercury will touch 30 – 31c.

UAC formed over SW Bay of Bengal, likely to intensify into a LOW in next 24-48 hour

UAC formed over SW Bay of Bengal, likely to intensify into a LOW in next 24-48 hours.

Upper Air Circulation formed over South West Bay of Bengal likely to intensify into a LOW Pressure Area in next 24 to 48 hours. This is likely to increase the rainfall activity across TN from tomorrow. This increased rainfall activity across TN and Kerala likely to continue until Diwali day.
Yesterday’s Depression over East Central Arabian Sea will move Westward and intensify into a Deep Depression by today.
Heavy rainfall is expected to commence over Coastal TN from tonight or tomorrow morning. Further heavy rainfall likely in one or two places over Kerala in the next 24 hours.
Chennai – Day to remain cloudy, one or two spells of rain or thundershowers possible in some areas. Day temp likely to be around 31C.
Coimbatore – Generally cloudy sky, with possibility of rain or thundershowers in some areas. Day temp to be around 31C.
Tiruchirapalli – To remain cloudy, with light rain possible. Temp to be around 33C.
Madurai – Generally cloudy, with showers or thundershowers possible in some areas, day temp to be around 32C.
Vellore – Day temp to be around 32C, light rain possible.

Possible depression in Arabian Sea

Another tropical disturbance in the Arabian Sea has shown signs of development and it is expected to intensify into Deep Depression in the next 24-48hrs. TN interiors and Coastal pockets have been getting good rainfall for the past two days. Isolated heavy rainfall would occur in one or two places over Western districts of Coimbatore, Nilgiris and Erode. Amongst the coastal regions, Nagaipattinam, Tuticorin & Ramanathpuram also would see some moderate to heavy falls. North coastal districts like Chennai, Tiruvallur, and Kanchipuram would also see isolated rainfall activity around noon.


Northeast Monsoon rainfall is expected to turn active from November 7th with a possible disturbance evolving in SE bay and it might enthrall us during the Deepavali celebrations. The conditions in the bay are being closely monitored over the developments.

Max temp is expected to be one or two degree above normal along major parts of Peninsular India and this includes Tamil Nadu cities as well.

Rainfall warning for District(s):

Coimbatore, Erode, Nilgris, Nagai, Ramnathapuram, Tuticorin, Vellore, Chennai, Kanchipuram, Tiruvallur might see isolated heavy rainfall.

Heavy Rains to continue across interior Tamil Nadu

The Upper Air Cyclonic Circulation(UAC) over east central Arabian Sea off Karnataka Coast continues to persist and is seen extending up to 3.1 km above sea level. Under its influence a Low Pressure area could form in the same area within the next 12-24 hours. Meanwhile, further to the east and north in the Bay of Bengal, another UAC is seen to persist near North Andhra Pradesh coast. Under the combined influence of these two circulations and the seasonal (Inter Tropical Convergence Zone/Seasonal Trough)ITCZ seen located in the region, the atmospheric flow patterns in the south peninsular region would continue to support convective cloud formations leading to Thunderstorms and rains across much of interior TN , south interior Karnataka and parts of Rayalaseema during the next 24 -36 hours. Meanwhile, the extreme south east Bay and the adjoining Andaman Sea is kept on a watch for a probable genesis of a “Tropical Low”.



Heavy Rainfall Districts:

Nilgiris, Coimbatore, Erode, Salem, Dharmapuri, Karur, Dindugul, Theni, Krishnagiri.

Moderate Rainfall Districts:

Delta districts, Chennai, Kanchipuram, Vellore, Thiruvallur, Villupuram, Thiruvanamalai.

City Forecasts:

Chennai will be cloudy, isolated areas may experience moderate rains, max. temp will be settling around 31 C

Madurai will have cloudy skies and rains could be expected in isolated places. Max. will be close to 29 – 30 C

Vellore will stay cooler at 29 – 30 C. Rains/Thundershowers expected in some parts of the city.

Coimbatore can experience some Thundershowers and day time max. will stay around 30 – 31 C

Trichy can expect some rains/Thundershowers and maximum temperature will hover around 31 C

Rains to increase in interior parts of TN

A disturbance persist in east central Arabian sea off coast of Karnataka and it is expected to develop into a low pressure in the next 48 hours. This disturbance remains in a area of favorable wind shear due to the presence of an upper anticyclone positioned over it Sea surface temperature looks favorable,with a threat of dry air which would inhibit any significant development. Computer models are showing some slow development of this system as it moves westward in the coming days. Widespread heavy rain is likely for coastaland South Interior parts of Karnataka due to this system. Isolated Thunderstorms are expected for the north and central TN coast, while Interior TN would be getting widespread heavy thunderstorms.


Heavy rainfall districts:
Coimbatore, Salem, Erode, Karur, Dindugul, Salem ,Ghats along Nilgiris, Dharmapuri and Krishnagiri.

Moderate rainfall districts:
Thiruvanamalai, Vellore, Villupuram and South TN.

City Forecast
Chennai : city will see max temperature moving closer to 31C. Rains are likely in the afternoon time.

Coimbatore : Max temperature will be around 30C.Thunderstorms can be expected during evening/night.

Madurai : City will be pleasant as the max temperature will be inching close to 29C. Sky will be cloudy with a high Probability of thunderstorm during evening/night.

Vellore : Temperature will be around 30C.Chance of rain is high during evening hours.

Trichy : Thunderstorm are likely during later part of day with temperature settling close to 32C.

North Interior Tamil Nadu to get very heavy rainfall

The Upper Air Circulation (UAC) over Lakshadweep Sea is expected to move north by tomorrow and will lie in parallel off North Kerala / South Karnataka Coast. The trough in the easterlies which runs from Lakshadweep to North East India also shifts up from the above UAC in the Arabian Sea through Salem, Dharmapuri, Krishnagiri, Vellore, Tiruvallur district and passes through the new UAC formed in the Bay of Bengal off AP/Odisha coast.


Heavy Rainfall districts:
Nilgiris, Salem, Dharmapuri, Krishnagiri, Vellore and Tiruvallur districts

Moderate Rainfall districts:
Coimbatore, Erode, Tiruppur, Tiruvannamalai, Kancheepuram and Chennai district

Chennai: The trend of daily rains is expected to continue with rains in the afternoon / evening. Maximum will be around 30-32C.

Vellore: Light Rains are expected with temperature settling to at 31-33 C.

Madurai: Temperature will range between 32-34 C and stray thunderstorms are expected during the day.

Trichy: Light to moderate rains are expected in the city with mercury settling close to 31-33 C.

Coimbatore: Temperature to be above normal at 32-33 C with rains expected in the city.

More Rain expected due to Trough & UAC

Rainfall occurred at many places over coastal Tamil Nadu including Chennai city. The upper air trough in the easterlies from South-West to West- Central Bay of Bengal extending upto 2.1 KM above sea level persists. The upper air circulation over Sri Lanka & Adjoining Comorin area extending upto 4.5 KM above mean sea level also persists. This would bring tropical downpours at most places over Kerala and many places over Coastal Tamil Nadu, parts of Interior & South Tamil Nadu and Puducherry. Chennai city will be welcomed with early morning showers and few scattered spells during the day.
A western disturbance would affect eastern Himalayan region from 2nd November onwards.
Rain would occur at few places over coastal Andhra Pradesh, Coastal Karnataka, Telangana & Rayalaseema, Sub-Himalayan West Bengal, Arunachal Pradesh, Sikkim, Bihar, Gangetic West Bengal and Odisha. Dry weather would prevail over rest of the country.

Chennai – Early morning showers and few spells of rain in day time over many parts of city with Max Temp of 32c
Vellore – Fair and cloudy weather with a thunderstorm in the afternoon. Max temperature may touch 32c
Madurai – Mostly cloudy conditions will prevail. Max temperature may touch 32c
Trichy – Light fog in the morning. Thundershower possible in day/evening. Max Temperature would be around 32c
Coimbatore – Thundershower possible in the evening over parts of city. Mercury may touch 33c

North East Monsoon
The Great Bhola cyclone remains the deadliest tropical cyclone ever recorded and one of the deadliest natural disasters in modern times. Nearly 500,000 people lost their lives in the storm, primarily as a result of the storm surge that flooded much of the low-lying islands of the Ganges Delta. The cyclone formed over the central Bay of Bengal on 8th November ,1970 and traveled north, intensifying as it did so. It reached its peak with winds of 185 km/h (115 mph) on November 11, and made landfall on the coast of Bangladesh the following afternoon.

Chapala Super cyclone in the making

The Upper Air Cyclonic Circulation (UAC) off the Sri Lankan coast continues to bring rains to coastal areas of TN. Heavy rains are likely to pound most places in Tamilnadu and Pondicherry over the next few days. Interior parts of TN will see some moderate to heavy rains in the coming days. Another easterly wave is a likely event after 5th November. The Extremely Severe Cyclonic Storm Chapala is expected to intensify into a possible Super Cyclone and move westwards towards North Yemen and adjoining Oman coast in a few days time.


Heavy to very heavy rainfall districts:
Chennai, Cuddalore, Karaikal, Tuticorin, Ramanathapuram, Kanyakumari

Light to Moderate rainfall districts:
Kanchipuram, Tiruvallur, Tirunelveli, Namakkal, Madurai

City forecasts:
Chennai – ‘Detroit of India’ will see moderate to rather heavy rainfall in isolated places with formation of more cumulus clouds through the day. Maximum Temperature would be around 32c

Vellore – Maximum Temperature around 33c. Cloudy skies will prevail. Likely to see a one or two thunderstorm development.

Madurai – Maximum Temperature would be around 32c. Moderate Rain expected in this region.

Tiruchirappalli – Temperature to remain around 31c with some scattered falls.

Coimbatore – City may see a comfortable temperature in the vicinity of 30c with scattered clouds. Light rain may not be ruled out.

NE Monsoon Active over Coastal TN

The Low formed over SW Bay of Bengal has weakened, but the associated Upper Air Cyclonic Circulation (UAC) is still seen in the same area. This is likely to bring more rainfall across Tamil Nadu and Kerala.
Heavy rain likely in many places across South TN and Kerala and in isolated places over North Coastal TN and Interior parts of the state. Isolated showers likely over Rayalaseema, SI Karnataka and Coastal Andhra.

Heavy to very Heavy Rainfall for Districts:

Chennai, Kanchipuram, Tiruvallur, Nagai, Chidambaram, Pondy, Cuddalore, Tuticorin, Rameswaram and Ramanathapuram.

Light to Moderate Rainfall for Districts:

Vellore, Tiruvannamalai, Salem, Namakkal, Karur, Madurai, Dindigul and Theni

City Forecasts

Chennai – Sky to remain cloudy with the possibility of one or two spells of rain or thundershowers. Temp likely to be around 31C.

Coimbatore – City to remain cloudy with occasional showers. Temp to be around 30C.

Madurai – One or two thundershower possible. Day temp likely to be around 32C.

Tiruchirappalli – Generally cloudy sky with one or two spells of rain or thundershowers. Day temp to be around 32C.

Vellore – Sky to remain cloudy with one or two spells of rain or thundershower. Temp likely to be around 31C.

Northeast Monsoon sets in over South Peninsula

After a couple of days of delay, finally Monsoon has made a breakthrough over TN, Kerala & parts of Karnataka & Andhra on 28th October as most of the coastal regions and few parts of interior reporting moderate to heavy rains under the influence of a weak disturbance in Bay of Bengal. Few days back official agency, IMD had already indicated the possible onset conditions falling on 27/28th October so now with the necessary criteria being met, IMD has officially declared the onset. The disturbance in bay likely to persist and move close to TN adjoining Sri Lanka so moderate to heavy rain would occur over most parts of coastal TN & Isolated heavy rainfall would occur over one or two regions. Few interiors would see moderate rainfall for next few days.


Moderate to heavy rainfall warning for district(s)
Villupuram, Pudukottai, Kanchipuram, Tiruvallur, Kanyakumari & Chennai

Heavy rainfall warning for district(s)
Tiruvarur, Nagapattinam, Cuddalore, Ramanathpuram & Tuticorin