Southwest Monsoon 2021 has defied the official withdrawal date and is unlikely to commence anytime soon. The western most posts of Jaisalmer and Barmer have recorded decent showers during the past 24hours : Barmer-13mm and Jaisalmer- 5mm. Also, intermittent light to moderate showers lashed other parts of the state : Jodhpur, Udaipur, Kota, Bundi, Chittorgarh and Ajmer recorded sporadic showers.
Earlier, the stipulated withdrawal from extreme West Rajasthan was slated with effect from September 01. This was revised last year and the new date from the last posts of Rajasthan has been fixed at September 17. Withdrawal dates have been shifted by 7-14 days across most parts of the country including the national capital, where the new date is taken as September 25.
Variability of monsoon withdrawal is also large as it is in case of onset. The difference in the two being : withdrawal is always retrospective and the onset is on real time basis. The onset dares have been revised based on past data from 1961- 2019 and withdrawal dates commensurate with data set from 1971-2019.
In the year 2019, the southwest monsoon commenced withdrawal rather late on 09thOctober and got completed in the shortest record time of 8 days, on 17thOctober. During last year 2020, the process started late yet again, on 28thSeptember and delayed withdrawal completes a hat trick with 2021 following same track.
The withdrawal process is invariably complete from the South Peninsula by 15thOctober. That is also the time to welcome Northeast Monsoon, tentatively from 20thOctober onward.
A visible change in the atmospheric conditions have to precede before the announcement of withdrawal. The rains over the region, by and large have to cease and the reversal of wind pattern to drier northwesterly has to follow.
Drop in the humidity along with mostly sunny days become a norm. Rise in the day temperature at least for a week or two, nearly coincides with the 2nd summer for the region.
Courtesy low pressure area persisting over East Rajasthan and West Madhya Pradesh, rains continue to visit the state. After the current spell, yet another wait in the wings.
The cyclonic circulation over the Bay of Bengal has moved inland and will soon cut across the central parts to reach in the proximity of East Rajasthan. This weather system will push the monsoon rains, right till month end and hopefully recede thereafter.