Synoptic Situation today (Thursday):
The Monsoon trough continues to run North of the normal position and runs along the Himalayan foothills. Meanwhile the off shore trough along the west coast remains strong due to Wednesday's embedded vortex.
The Eastern trough has shortened and lies from Sikkim to the Bay.
The vortex has weakened on Thursday itself, weakening the off shore trough along the west coast.
An UAC has formed in the North Bay, and is at around 500 hpa.
It is likely to descend to sea level as a low by the 21st, Saturday, as a low at 998 mb. Should be positioned at around 20N, off the Orissa coast.
As it is likely to remain over the waters till Sunday, it could deepen to 996 mb, or even 994 mb by Sunday. Low will move west on Sunday/Monday and most likely fizzle out in the region around Vidharbha.
Once the low forms, we can expect the monsoon axis to slide southwards. It could be positioned from Pakistan thru Rajasthan thru North MP and Chattisgarh into the Low.(See Map)
Consequently, the West coast trough could strengthen and activate again.
Outlook Summery for Friday 20th/Saturday 21st and Sunday 22nd:
Good Rains Likely in Vidharbha, Eastern Marathwada, Konkan, North interior AP, Chatiisgarh and Eastern MP
Heat likely in Rajasthan and adjoining Sindh (Pakistan)
Friday: The Monsoon Axis remains in the North, hence heavy rainfall is expected in UP. Region around Lucknow can recieve heavy rains on Friday.
Precipitation remains good in South Konkan/Goa, but decreases in the North Konkan region.
Saturday: As the UAC descends, rainfall in the SW quadrant of the UAC/Low increases. We may see some precipitation gathering strength in the North MP, and adjoining Vidharbha. Rains will be heavy in the Ramagundam region of AP. Light rains, upto 10 mms penetrating into Interior Karnataka and Madhya Mah.
NW India and Gujarat almost dry with no meaningfull rains.
Strong Westerly winds blowing in Saurashtra.
Sunday: Heavy rainfall area spreads a little to the west, with Vidharbha region and adjoining Marathwada and North AP getting very heavy rains. Madhya Mah too will get medium to heavy rains.
Rains will also increase along the Karnataka coast and entire Konkan belt. As the Monsoon axis moves south the off shore trough gains strenghth by Sunday.
Friday/Saturday/Sunday: For Pakistan, rains will be restricted to the Northern plains. Light rains in the North. Lahore can get some light rains.
Sindh will be dry and hot. Hot westerly winds will sweep the sindh regions, raising dust storms in some regions.
Karachi will get light drizzles, but Hyderabad will be dry, and day temperature could touch 41c. Sukkur will be dry and hotter with the day temperature at 43/44c.
I do not think there will be any effect of this low in Pakistan...but we will observe and follow the developments.
Mumbai: Gone are the signs of rainy and monsoon days..at least till Sunday !
Friday: Partly cloudy with 3/4 showers throughout the day, out of which a couple of them will be heavy in some parts of city. Rain Amount: 20 mms.
Saturday: sunny spells and partly cloudy by afternoon. showers by late afternoon/evening. But not persistent, and distributed in parts of city. Rain amount: 10-15 mms
Sunday: generally cloudy, with more frequent showers. Intensity increasing by evening, and getting heavier. Rain Amount: 30-35 mms.
Pune: Hate to put up such a miserable forecast for this city ....hopefully a better forecast from Monday !
Friday/Saturday: Partly cloudy. Few light showers or drizzles in some parts. Rain Amount: 5-7 mms.
Sunday: Cloudy in the day with light drizzle. A light shower expected in some parts by evening. Rain Amount 5-10 mms.
Surat: Friday/Saturday/Sunday: No definite indications of any meaningfull rains approaching..partly cloudy with upto 5-10 mms/day.
Delhi: Friday/Saturday might see light drizzles in some parts, more likely on Saturday afternoon.
But Sunday will be dry and hot. Weekend temperatures to touch 40c and maybe cross 40c in NCR somewhere.
Bangalore: This city need more rains urgently...this is only an expression..and sadly the forecast is nowhere near it...Again, no rainfall increase seen these days. Just about 5 mms/day in some areas.
Chennai: Not much rain expected this weekend for the city.
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