New Delhi: The National Weather Forecasting Centre/Regional Meteorological Centre, New Delhi of the India Meteorological Department (IMD) has said:
Southwest Monsoon covered entire country today, the 26th June 2020.
The Southwest Monsoon has further advanced into remaining parts of Rajasthan,Haryana and Punjab and thus it has covered the entire country today, the 26th June 2020(Fig. 1).
The normal date for Southwest Monsoon to cover entire country is 8th July. Therefore, theSouthwest Monsoon this year has covered the entire country 12 days prior to normaldate.
In the recent past, such early coverage of Southwest Monsoon over the entire countryoccurred in 2013, The Southwest Monsoon covered the entire country on 16th Juneduring 2013.
During past 24 hours, there has been fairly widespread rainfall activity over WestRajasthan and adjoining Punjab & Haryana in association with the cyclonic circulation at lower tropospheric levels over northeast Rajasthan.
Considering southwest monsoon onset and advance over the country as a whole, there has been normal progress over south and east India, about a week delay advance over northeast India and about 7-12 days early advance over central & northwest India. The early advance over the central & northwest India was facilitated by formation of a low pressure area over Bay of Bengal which moved west-northwestwards and another cyclonic circulation over central India.
Update for ongoing intense southwest monsoon rainfall spell over northeast &
adjoining east India
Current Meteorological Conditions
Eastern end of the monsoon trough at mean sea level lies close to foothills of Himalayas.
Another trough runs from Bihar to east Vidarbha at 3.1 km above mean sea level. It is likely to perisists tilltomorrow.
There is high convergence of strong moist southerlies/southwesterlies winds from the Bay of Bengal overnortheast & adjoining east India and same is likely to continue for next 2-3 days. .
Forecast & Warnings
With the above favourable meteorological conditions, the enhanced rainfall/thundershowers activity ismost likely to continue over the northeastern states &adjojinig east India during 26th & 28th June withlight to moderate widespread rainfall over Bihar, Sub-Himalayan West Bengal & Sikkim, ArunachalPradesh, Assam, Meghalaya, Nagaland, Manipur, Mizoram & Tripura and decrease in spread &intensity thereafter.
Heavy to very heavy rainfall at a few places with extremely heavy falls (≥ 20 cm) at isolated places verylikely over Sub-Himalayan West Bengal & Sikkim on 26th & 27th and isolated heavy to very heavy falls on28th June, 2020.
Heavy to very heavy rainfall at isolated places with extremely heavy falls very likely over Assam &Meghalaya on 26th & 27th, isolated heavy to very heavy falls on 28th and isolated heavy falls on 29th June,2020.
Heavy to very heavy rainfall at isolated places with extremely heavy falls very likely over Bihar on 26th &27th, isolated heavy to very heavy falls on 28th and isolated heavy falls on 29th June, 2020.
Isolated heavy to very heavy falls is also very likely over Arunachal Pradesh on 26th & 27th and isolated heavy falls on 28th June, 2020.