The India Meteorological Department (IMD) has forecast ‘heavy to very heavy rain’ in Mumbai and Thane on Wednesday and Thursday, while issuing a red alert for Palghar for the same days. A low pressure area that is likely to intensify into a cyclonic storm in the Arabian Sea will result in pre-monsoon showers at least until Thursday.
The usual date for onset of monsoon in Mumbai is June 11 every year. However, the actual onset varies depending on weather systems, and last year, it was delayed till June 25.
On Sunday, a low pressure area formed over south-east and adjoining east-central Arabian Sea in the early morning and remained till forenoon. It is very likely to concentrate into a depression by Monday and could intensify into a cyclonic storm over east-central Arabian Sea. It is very likely to move nearly northwards initially until June 2 and then recurve north-northeastwards and reach near north Maharashtra and south Gujarat coasts around June 3.
Owing to this, IMD has forecast that Maharashtra, especially its west coast, will experience a wet spell between June 1 and 4. IMD has issued a red alert (extremely heavy rain at isolated places) for Palghar district for Wednesday and Thursday. It has issued an orange alert (heavy to very heavy rain at a few places) in Mumbai and Thane for the same days. Meanwhile, all three districts will get rain and thundershowers on Monday and Tuesday.
Owing to high wind speeds and sea conditions being very rough, fishermen were asked to return to coast on Sunday itself.
Commenting on the situation after June 4, Akshay Deoras, a Ph.D scholar at University of Reading, U.K., who follows India and especially Maharashtra’s weather, tweeted, “From 4 June, normal #weather conditions (mostly clear sky & humid weather) will make a comeback in #Mumbai. This period will witness at the most a few odd passing pre-#monsoon showers. It will be surprising if the #monsoon’s arrival in #Mumbai is announced before ~15 June. The Arabian Sea low-pressure system will lead to a transient rainfall phase, but surface/near-surface wind pattern won’t be westerly so as to declare the monsoon’s arrival. I’d like to cite the case of Cyclone Vayu which didn’t allow the onset of westerly surface/near-surface #monsoon winds over #Mumbai for a long period around mid June 2019. Due to the same reason, @Indiametdept had waited for many days for announcing the monsoon’s arrival.”
Source: https://www.thehindu.com/news/cities/mumbai/wednesday-may-bring-rain-to-mumbai-thane/article31718592.ece