Sunday, June 03, 2012


No, there is NO anti-cyclone in the Arabian Sea resisting the SWM progress into Kerala. 
There is no hindrance of a low "sucking" in the SWM away from the Indian Coast. In fact, the existing low has already faded from sea level and has become a "favourable- for -the-monsoon" UAC ! 



The SW winds are strong enough to bring in the monsoon, they have been since the lasy 2 days, and are now blowing at an optimum 30 knts in the central Arabian sea. 


The SWM should then move into Kerala! What's the delaying it now ? It should (have) hit the Kerala coast by today, 3rd June. That's what Vagaries has been harping on since the last 10 days ! What's stopping the SWM now ?


After a thorough detailed scanning of all the factors, and studying the parameters individually, (it was puzzling), I think I have hit upon a minute and to an extent a significant parameter that is playing spoilsport. 
A para meter that could have been overlooked by many a forecasters. 


The SST off the Somali Coast is still above normal ! The Somali current factor, one may recall, has been stressed by Vagaries in almost all the MWs. And it seems it is creating the hindrance to a SWM advance.


The role this factor plays has been explained in many a MWs. The SST off the Somali coast should be cooler, much cooler by at least 10c, from the Central Arabian Sea. As the cool winds blow from the Somali Coast region, they sweep over the warmer Arabian Sea, and form mass clouding, Monsoon cloudings. 







In fact, this small but significant factor is playing on. As the latest SST map shows, the Sea temperature off the coast is still above normal by around 1.5 to 2c.
Without detailing, I would say it has created an un favourable wind shear in the Arabian Sea.


Now, something to cheer up. The SST off the Somali Coast can, in the present conditions (without any system interference) cool down fast, maybe in the next 36 hrs !
Presently, it needs to drop by another 2/4c, and it IS possible to happen sooner than expected. Look out for mass cloud formation off the coast, indicates cooler air condensing quickly.


Therefore, the Monsoon has been "trying" to creep into Kerala as a weak current for the last 2 days. 


Yesterday, Kerala stations recieved between 4 cms- 8cms of rain and today the rainfall was:
Vadakara, Vaikom, Enamackel 3 cm, Thrissur, Kudulu and Chalakudy and  Kottayam 2 cms each, Cial kochi, Piravom and Kodungallur 1 cm each.


Meanwhile, the SWM has advanced into Meghalaya and assam and a few other NE States (see advance map on Current weather Page).
Tezpur 16, Karimganj 15, Mushalpur (AWS) 14, DRF 12, Cherrapunji 11, Motunga 10, Biswanath chariali(AWS) 10, Badatighat 8 and Beki-mathanguri 7

11 comments:

Viravanalluran said...

Dear Rajesh Sir,
Here we too are thinking in the same line. We could see SST values off Somalai coast and just down south and west of Kanyakumari. I was told that this region comes under East IOD region too. My boss on verifying 03.06.2012 rainfall over Kerala and the lone rain fall reported in Tamilnadu at Uthagamandalam_agro AWS, come to a conclusion that weak SWM may hit Kerala coast near or between 10 to 13 Deg N latitude within another 36 / 48 hrs.

Bhavik Shah said...

Currently there are monsoon clouds extending from Mumbai coast all the way to south. This is something intresting. My guess something different will happen this year, monsoon will hit the whole of west coast from Goa to Kerala at the same time within next 48 hrs.
The delay in Kerala is due to the low that formed last week. But since this low did'nt turn into the cyclone, it will actually help bring SWM early for the entire West coast

Shitij said...

I don't understand why the low doesn't turn into cyclone??? If you see the temperature of northern Arabian sea it is still above 28C which should help in the development of the system.

Bhavik Shah said...

Low did'nt turn into cyclone because of the high temperatures present in the Arabian sea west coast and the interiors of the sub-continent.
The low thankfully was pulled by the sub-continent and slowly it will bring SWM to west coast.

rajesh said...

Bhavik/Shitij:There is no need to be confused. If you recall, from day 1 of the announcement of the low formation in Vagaries (10 days ago), i have been stating that it will be present in the A.Sea for 2/3 days only. There was no question of it forming a DD, leave alone a cyclone. It was expected to fade away as it would track a short distance into the cooler waters of the western A.Sea.
Now, only thing to wait for next 24/36 hrs is the SST near the Somali coast. And the wind shear.
Anyway..i shall discuss this and the SWm progress, and future expectations in the evening publication. By 10 pm IST (Please recall the MJO thing I have mentioned in MW).
Viravanalluran: Thanks for the feedback. Yes, I have mentioned earlier too, a weak Monsoon is expected initia;;y, I agree with your boss. There are other factors supporting this, which I will put up tonite. Awaiting your comments on that..

Bhavik Shah said...

From the satellite images I can see a weak S/W monsoon winds blowing over south Karnataka and some parts of Kerala. By today or latest by tomorrow monsoon will enter the sub-continent with force

Shri said...

I am not sure...but i have heard in the news that due to a low formation in South-East Asia , the monsoon is getting delayed.Is it one of the reasons why monsoons is getting delayed..Rajesh. ??

Anonymous said...

hi All doing a great job.

Anonymous said...

i m from pakistan,sindh,karachi i wish that u also predict for my city...and a question.....THIS YEAR 2012 IS THE YEAR OF CYCLONE is it true? it is about Arabian sea

Bhavik Shah said...

Good News ---- Monsoon has set in Kerala

Pavan said...

Saswad a smal twn ese of pune 19km frm hadapsar, since last 1hr heavy rain with gusty winds lashng