Mumbai, Konkan and south Gujarat have been spared of heavy rains normally expected of a westward-bound rain being attracted to a low pressure system in the region of Gujarat.
Now, the low has fizzled out and moved away westwards in the Arabian Sea.
IMD streamline shows a fresh southerly winds being pulled in by activity in the west Pacific. This has resulted in good cloud formation over coastal Karnataka from Monday.
A round of revived monsoon rains will cover the west coast, pulling the rain up towards Konkan/Goa by Thursday.
A vortex forming in the north Konkan area is possible.
Hence, I expect Mumbai to get good rain on Thursday and Friday. Begining late Wednessday night, on Thursday, Visarjan Day, I expect at least 70 mms of rain in Mumbai. Thursday Morning/afternoon will see most of the rains. It could well be a wettish day for festivities. The rain amount will lessen to 30 mm on Friday.
Later, these rains will push into the south Gujarat coast.
We can now safely look out in the west-central Bay of Bengal and the neighbourhood for signs of a low-pressure area around September 3 (Thursday).
An upper air cyclonic circulation is already present over this region. It is expected to descend to the lower levels and deepen to form the ‘low.’
Today, ECMWF and IMD streamline maps show a line of discontinuity across north peninsular and adjoining central India today. As a result, the northern end of the line, H.P. got a very good bout of rains/snow. The day temperatures remained wintry and Kufri resort had a high of 14c on Monday, with Dalhousie at 15c during the day.
Now, a ‘low’ could get embedded into this trough by end of this week.
Thus the entire northern regions of the country would be brought under precipitation. This could last till September 10.