Northeast Monsoon rainfall is very likely to turn vigorous over Tamilnadu and AP

As predicted by Numerical weather models , a low pressure area has formed over Southwest bay of Bengal adjoining equatorial Indian Ocean. It is likely to move in a NW direction and come close to Tamilnadu. With Marginal support of atmospheric conditions , it has good chances to intensify into Well marked low pressure area and has “marginal chances” to intensify into Depression in next 48-60hrs.

Rainfall activity is likely to pick up its pace from tomorrow onwards over coastal as well as interior areas of Tamilnadu. Moderate to heavy rain likely over many places in coastal areas tomorrow, 11th of November

With low pressure area closing in, Easterly surge will be amplified due to which, rainfall is expected to increase from 11th nov early morning onwards. Heavy to very heavy rains are expected over North coastal Tamilnadu, delta districts and South AP coasts from 11th of Nov and will continue upto 13th Nov. South TN will also see heavy to very heavy rains at scattered places.

Huge amounts of moisture advection is seen straight from PBL to mid levels of troposphere which can bring strong and sustaining rain clouds.

There is a possibility of lock mechanism happening at Mid levels of troposphere with ridges on either side and weak westerly trough over North India and WML vortex near us, which could enhance rainfall over coastal’s and interiors. So due to these following factors, localised extreme spell of rain at very isolated places cannot be completely ruled out over coastal TN and KTCC districts.

Forecast for Chennai city and surrounding areas

Rainfall is expected to pick up from tomorrow onwards with heavy intermittent rains likely tomorrow night. Heavy to very heavy rains with breaks are expected over many parts of city and suburbs from 11th to 13th. And heavy rains are likely on 14th November too.