Wednesday, October 08, 2008

With the 200 hpa westerly jet stream gradually pushing its way south, now having come down to 26N, the south-west monsoon has to give way and recede further down south.
As per my last blog, the winds and the jet stream patterns, and the atmospheric conditions, show, and, as per my assumptions, confirm with the complete widhrawal of the monsoon from all regions north of 20N.
The last of the stray isolated thundershowers will pop up in Maharashtra on the 8th. ,and, I feel, the monsoon should be bidding farewell to Maharashtra, Goa, North Karnatak and A.P. from the 9th.
By next week, the reversal of the south-west winds would be complete in the peninsula area, and the westerly jet stream should slide to the regions below 15N. Hence, it would be safe to predict the North-East Monsoon current to be picking up and rain bearing systems to start forming for the commencement of the reverse monsoon thereafter, say around 14th./15th. of October.
For the north-east monsoon systems to form, the influence from the equator region decreases, and the formation of a system in the bay directly depends on the strenght of the north-east winds, and the high pressure in the north China region, which is the main "power house".

The northern regions of the sub continent, are now getting some showers/winter rains due to a fairly active W.D. crossing the belt along N.Pakistan/H.P./Kashmir regions. Higher reaches in Ladakh had snowfall today. A sharp drop in night temperatures in the northern regions is expected once the skies clear on the passing of the W.D.

Some meteorologists and a few forecast models had foreseen the formation of a cyclone in the Arabian Sea by the 2nd. week of October. I do not see any signs of a cyclone forming off the west coast of India in the next 15 days at least. I limit myself to 15 days now, as the formation of a cyclone in this area is directly related to the "October heat" in the region. So, a lot depends on how much the land would heat up in the first 2 weeks of October.
kapadias@gamil.com

2 comments:

Anonymous said...

mr rajesh,
the rain have started in chennai from today 11th. It has been raining from 9:30 pm on and off. I believe the N.E monsson is in the process of setting in. I need to know if any forecasts has been made on this year N.E monsoon

rajesh said...

Forecast of the N.E. monsoon is been made on the IRI site. That is an overall forecast of the 3 months is made on the site.
Refer to my blog of 8th. and 12th. for my observations of the progress of the reverse monsoon.

Estimated amount of rain will be made by me periodically by observing the actual developments.