Thursday, September 08, 2011


We will now shift our attention eastwards towards BB-6. Located at sea level and at 998 mb over Jharkhand, it is generating rainfall in Orissa and parts of Jharkhand on Thursday.

Where will it track ? Normally, as per met. "rules'', it should travel in the corridor "provided" for it, that is the monsoon trough line. Today, the axis is along the line from Jaisalmer (Rajasthan) thru Varanasi (South U.P.) thru the system into the Bay.

It is probable that the Western end of the axis might just shift a bit Southwards.The system may move along it, with moisture support from the Bay, as the East winds above the axis are strong. But, there are more chances of the West wind South of the axis dominating, being stronger than the Easterlies. In such a case, we should see more clouding and precipitation South of the system along the route. Hence precipitation wise, we will have rains on Friday in Jharkhand, Chattisgarh and adjoining East M.P.

This forecast map is prepared on Thursday night, and the rainfall is projected progressively from Friday, 9th thru Sunday 11th.. (Moving westwards).See enlarged map here.



I feel BB-6, may not deepen much, and will track into Central M.P. region by Friday/Saturday. Meaning rainfall in M.P. and Vidharbha on Saturday. Nagpur can get rains on Saturday and Sunday.

Saturday/Sunday, BB-6 will then track towards South Rajasthan, with rains moving into Eastern Gujarat and rains commencing in the North Konkan/south Gujarat coast due to SW winds attracted to the system.
Delhi and adjoining Rajasthan regions will have cloudy weather with light rains this weekend. Mah. ghat stations (Mahableshwar/Lonavala) would again get good rains this weekend.

SE winds can push some rainfall into central Nepal ,and Kathmandu on Sunday/Monday.

System will persist in the extreme west position shown in map for a day or so, and precipitation in West M.P, Saurashtra and North Konkan will continue into Monday, albeit lesser amounts. We are not expecting extreme heavy rains in this case in Gujarat or Konkan.

Frankly, according to me, precipitation moving beyond Saurashtra or East Rajasthan into Pakistan is doubtfull.

Mumbai:

Friday: Partly cloudy, with sunny spells. A few passing type showers. Rain amount upto 10 mms.

Saturday: More clouding, with passing showers, a few heavy. Rainfall frequency increasing slightly from night. Rain amount 20-25 mms.

Sunday: Cloudy with intermittent showers. A Heavy shower possible in evening with thunder. Rain amounts 30-35 mms.

Pune

: Chances of Thundershower on Saturday evening. Sunday cloudy with thundershower in the evening.


There will no updates or articles next 4 days, as I am going to Kaas Plateau of Flowers. Located in the Maharashtra Western Ghats, its a place to see natural carpets of flowers, and the right season is now. Shall put up pics in the links on Vagaries.
Next article will be in place on Monday night.







3 comments:

svt said...

Apparently La Nina conditions have returned in pacific. North-east monsoon could be very good this year. And I personally feel that Mumbai might get surplus rains in october & november just like last year. May be next poll should be about whether this year Mumbai (scz) will get highest annual rainfall in its history. We are not too for away from record. :)

sset said...

As stated earlier - Rajisthan,Gujarat,Saurashtra,Kutch are no more dry deserts but have become extreme rain intense areas. Recent fall of 400mm in 24hours over Saurashtra/Kutch has amazed us - infact all UAC,low pressures regularly cross - 8th time in this season and SW monsoon extends beyound sept/oct in these areas. These areas may become major fertile agricultural, forest areas - rice,sugarcane cultivation. This change in weather pattern over saurashtra/kutch over last 10years is subject of reasearch for weather scientist.

On other side southern India - interior karnataka,Rayalseems,TN,SriLanka are in path of desertification. No low pressures,UACs,vertex have ever formed- september also dry no rain. In fact 24hours max rain never crosses beyound 150mm. Also over the years we observe decreasing NE monsoon with less days and may or may not form. Even if cyclones form either do not cross TN or fail to produce rain.

Do we find any co-relation between increasing intense rains over central,Rajisthan,Gujrat,Maharastra and decreasing rain over southern India? Myself strongly feel this is happening.

sset said...

La Nina implies weaker NE monsoon - so southern India again runs into problem???