Saturday, September 10, 2016

Posted Saturday 10th Night:

BB-11 is expected to form on 11th as expected. It may track W/NW into Telengana and clouding in Western segment will bring rains to interior Mah next week. Rainfall expected in A.P./Telengana and Vidharbh next 2 days. It may track NE later and weaken further...

Conditions for Monsoon withdrawal may commence from West Rajasthan and adjoining South East Sindh from 13th September.

Chennai received heavy rains on Saturday, and between 5.30 pm and 8.30 pm, 52 mms were recorded at Minambakkam.
Hyderabad received 8 mms till 8.30 pm IST Saturday.

Southern Indian Peninsula Deficit at -13%:
The monsoon axis has remained in the far north, or more North than normal for a very long time now, almost a month (or more). When this happens, naturally, the seasonal low in the Kutch region becomes weak, or also moves North.
Now, as i have stated, the off shore trough along the west coast in monsoon season "pivots" and is anchored from the seasonal low in Kutch. If this gets weak, the off shore trough (west coast) weakens also. This has caused weak and deficient rains along Karnataka Coast (-31%) and Kerala (-31%) this year. 
Also, the position of axis (in North) prevented the formation of a trough or LWD in the Central Peninsula region this year. We have not heard of a trough forming North -South this year from any system positioned in MP, even though BB-6,7 and 8 went thru MP. With the syetems from the Bay, only the Eastern side of axis came Southwards, while the Western end remained far North.The Arabian Sea and Bay sytems are also "instigated" by favourable MJOs.
Thus South Interior Peninsula got less rains...NI Karnataka 0%,SI Karnatak -13%, 
Though Interior Mah (Maratwada -2% and Madhya Mah +7%) got rains from the BBs over MP. 

4 comments:

sset said...

Rajesh sir Vagaries - best scientific explanation given for "Southern India Scanty rains". No other blogs, nor IMD was able to explain this. Guess this is new discovery - where in even west coast goes dry. It may open new doors, new factors to predict droughts much early. Who know next few years may happen same?

Saurabh Dwivedi said...

@Rajesh
The figures from Northern parts are even worse.
Punjab -22
Haryana -21
Himachal -21
UP -12
UK - 9
J&K -5

To be precise other than Rajasthan(+35) and MP(+22) and to a far lesser extent Maharashtra(+3), AP(+2) and Bengal(+3) every state has received less than the average rainfall.

Far far better than the last two years but not exactly the surplus monsoon that was expected.

Still three weeks to go but for sure northern parts are unlikely to see any significant reduction in rainfall deficit as the monsoon window is fast closing for these parts.

East, west and south still have a chance to get good rains. Lets see how things unfold.

Keep up the good work.
Regards
Saurabh

Jiva Bhammar said...

Sir what you expect for suarashtra in next week?any chance of good shower?

abizer Kachwala said...

Rajesh sir,Some forecasts which I have reffered to show heavy rain in mumbai -konkan region between 18-22september?Can you throw some light on it.please-your forecast about mumbai roha region ?