Monday, July 23, 2012


BB2 merges with the monsoon axis.....and the axis slides Southwards. An associated axis trough also aligns itself with the sea level axis at 850 hpa.


On going thru the Monday's Forecast put up yesterday, we see the rains have weakened in Vidharbha. (Chandrpur which recieved 223 mms in the 24 hrs till 8.30 am Monday, and then recieved 41 mms in the day till 5.30 pm Tuesday. But, all other stations in Vidarbha except Yavatmal (19 mms) managed less than 10 mms on Tuesday. Bhopal saw 28 mms.
Other regions in AP and N.I. Karnataka too had reduced rains Monday.


But, the big let down was the Konkan and South Coastal Gujarat..where we had expected 40-60 mms in the Konkan. 
What actually was measured was around 20 mms in the Konkan stations (till 5.30pm..we have the night still).


Surat too did not recieve any rains on Tuesday. 
Mumbai had a couple of showers in the afternoon. But, rains were forecasted to increase in the evening, so the 5 mms recorded till 5.30pm could still add up to the forecasted 20 mms. expecting sharp showers at night tonite.


All other forecasts (cities and All India) remain valid for Tuesday and Wednesday.


A new Low is being much discussed and mentioned in comments. It may be noticed that vagaries has not even mentioned its possibility as yet....I am not too sure of its date and strength ..whether it will be a low or an UAC...shall put up when i am convinced.



38 comments:

rajesh said...

All Vagaries Readers: It really saddens me when we, as a Vagaries' family start arguing and doubting each other. Please refrain from unkind worths to each other, and let us maintain the "family relations" that Vagaries is striving to keep.
Please bear in mind that vagaries has always respected, or even published on various pages, any usefull and informative matter (pertaining to Weather) sent by you all.

We have international readers, and to bring in any type of politics or "non weather" discussions on vagaries is a no-no.
All of you readers has made this blog sucessfull, and have full confidence you that all care for the reputation of vagaries as clean and honest...
in fact, i hope to make this blog more interactive and let us all know each other's view more often..weather wise :-))

BTW, what do you think of the new low? is it coming ?

sridhar said...

talking about being interactive... ever thought about making a smart phone weather app.:)...india seriously lacks a decent weather app unlike the west....

Pavan said...

Sir i pledge my apology if any of my words directly or indirectly to you or any respective readers of the blog

GSB said...

.....aapka hukam sar aankho par...

sset said...

It seems Sri Lanka is facing same velocity of drought as south peninsular India. Wonder it is directly proportional???

Chandrapur received 250mm of rain, yesterday it was 200mm - so 500mm in 2 days. Naughty place is trying to compete with Konkan??? Anyway good for tigers and oranges.

I wish atleast Bangalore gets 1 UAC this monsoon - all my tree plantations have started drying- we an IT group planted drought resistant fruit sapling for poor muncipal schools.

Thanks

METD WEATHER said...

IT will come and cause another rainfall event for Central India.

Rajan Alexander said...

Rajesh. IMD downgrade forecast to 92% LPA. Even that looks a long shot now.

But puzzling the rains:

- ENSO neutral
- IOD neutral with positive bias
- MJO favourable71 gViewar

Atul said...

Hi Rajesh sir,
How we can decide low will take which path? If you have already explained in earlier blogs please point me to that.
I don't know low will get created or not but if it gets created will travel through Maharashtra so that western Maharashtra will get much needed rain? If not can you please make it to pass through :) just kidding :). But we are eagerly waiting for rain here in Pune and western Maharashtra.

Thanks,
Atul.

Abhijit Modak said...

@ Rajesh Sir. Why this low BB2 not produce any meaningful rains for Konkan belt even direction of low was WWN dir ! Otherwise past years when Bay produces any low then off shore would get strenghthen and moisture flow from arabian would pass over Konkan to flow or gets attracted towards Bay Low which would produce flooding rains for Konkan ! But this year Bay low not activating Arabian flow !

rajesh said...

Atul: A system normally follows the "corridor" created by the monsoon axis. It actually also brings the axis down, and merges in it..situation can differ in rare cases.
Abhijit: You are grasping it well...yes ,that is the reason i had estimated good rains in Konkan and Mumbai for Monday. strong incomimg wind laden with rains rushes towards the low in the Konkan.

In rare cases, even if the low is still in the bay, then exactly opposite, on the same line, we see a heavy clouding rush on the Konkan coast. Its called a "sympathy" wave. But that is not seen since last year.

Anyway, this BB2, weakened off very fast, too fast, to give an opportunity for Konkan to get rains..even though vagaries had forecasted an early fizzling out, Konkan rain was expected on Monday. The off shore trough did not activate..but with the low away, and the axis south, it can still activate slightly...

GSB said...

I just ran my archive of monsoon cloud cover from 1st June 2012 onwards and I see that after the 11th of July very little cloud formation is visible over the Arabian sea. This is very unusual in this part of the season. Maybe with my limited experience (4-5 years) I might be missing something but definetly evaporation/convection over the arabian sea is lower dramatically after the 11/07/2012.

Whatever moisture laden clouds reach north konkan are probably spent by the time they reach here having started in the BB.

GSB said...

By the wy going on a holiday to Panchgani/Mahab for two days tonite. Will be reporting from there..

Ron said...

imd also predicting that monsoon axis will shift north again after 2 days...

Rajan Alexander said...

@GSB. I'm not sure of Arabian Sea side. In general, one of El Nino signals is less cloudliness. Till 3 weeks while Nino3.4 and SOI reached El Nino threshold levels, cloudliness remained La Nina like. Now it is the exact opposite

rajesh said...

heavy rains continuing since 10 mins here (Mahalaxmi)...

Pavan said...

Clear sky in pune nt even a drop frm morn very much worried july is almost over but we havnt crossd 100mm, hope for typical thundershowrs of august, if this case continus then may be pune may get max 300mm rain of these 122day season

Abhijit Modak said...

Here at Badlapur today 8.30am to 11.30pm period measured 15mm rains. There were occasional rains some time heavy but none of spells not lasting beyond 10 mins !

GSB said...

3.15 am at lonavala. Very very slight drizzle about 1 mm per hour all the way from Thane. Some places dry in between...

Abhijit Modak said...

Night too disappointing here, just 5mm added. So total (yesterday 8.30am till today 8.30am) in past 24hrs 20mm rains recorded at Badlapur.

emkay said...

Is the expected low in BoB a pulse of the storm expected today in HongKong ?

Shitij said...

Around 6am light rain in Surat but this rain was no meaningful as this rain lasted only for 5-10 min. At present sky is completely cloudy.

Pradeep said...

Dear Rajesh,

Chennai is very humid and not even a drop of rain on both 22 and 23rd July. Temperature is in higher side at 37 C. Cola predicts some rain on 24th Night. whats ur call.

Anonymous said...

Hello im john from belgium staying in delhi. Before coming here i was told to get ready for heavy rain in july and august but here in delhi scenario is totally different.And indian weather department(belgium weather department is much better) is predicting rains for the whole month but we have only 2-3 days that can called as rainy days.But i must say your prediction is very much accurate. keep doing this work.

Vijayanand said...

Agumbe showing some good numbers. 17 cms and 9 cms on subsequent days.

svt said...

Any chance of Typhoon Vicente sending pulse in Bay Of Bengal later next week. We badly need Depression in bay to cut down the rain deficit.

Anonymous said...

Very heavy shower in borivali at 11am..and agin now another heavy shower..seems short term forcasting falling correct...chetan

Vikas said...

Dear Rajesh-ji,

Thanks a lot for sharing your immense knowledge/understanding of weather for the benefit of others. This is my first post on your blog but i have been following it regularly since last few months.

Most of NW India is very dry this year and i am preparing myself for major water/power shortages in the coming months.

Today i read about Typhoon Vicente in China. My question is that wont it impact normal monsoon (whatever that was happening) in bay of Bengal? We were expecting some rains in coming days in Delhi and with this latest disturbance the possibility may go down even further.

emkay said...

I found South Mumbai to be very gusty around 10 AM. Swirling winds. Must be localised isnt it ?

Anonymous said...

Hi Rajesh,

In concurrence with what Rajan righly pointed out, if we face a 22% deficit despite
Neutral to Slight El-nino
Neutral IOD
Neutral MJO

i wonder what will happen if any or all of these factors turn adverse . Are we missing anything that will explain such poor performance. This has been the worst monsoon since 2002 and 1987. Although 2009, was low the rains were normal in catchment belts thus helping Rabi production.

Now with IOD turning negative, MJO going into dry phase and El nino a distinct possibility, will be end up with sub 30% deficit ?

Regards, Ananth

GSB said...

Panchgani experiencing light to medium showers from 10 am on wards.. must be 30_40 mm by now 4 pm. I also checked that Thane city has received 13mm since 00am today..

Vivek said...

Sangria in Punjab has revived only 12mm on rain this season! What are the prospects for a low developing over the northwest this week and therefore of good rainfall ?

Thanks,
Vivek

Abhijit Modak said...

Here Badlapur received 20mm rains from 8.30am to 5.30pm period today . It was full overcast day with no sun out. Rain started from 11am was continous in form of drizzle to light showers till 4.30pm. And in between there were also heavy spells with strong SW gusty winds.

Vivek said...

That should be "sangrur" in Punjab .

Vijayanand said...

http://www.weather.com/weather/map/interactive/INXX0012:1?interactiveMapLayer=sat&baseMap=r&zoom=8

At 2.30 pm , its clear on west coast from Goa to North Kerela. Good clouds over central India.

Vijayanand said...

The water level at the KRS dam yesterday stood at 88.90 cusecs as against the maximum level of 124.80 ft.
Very worrisome picture.
It has to reach 120 ft by end of sept.

Vijayanand said...

http://www.weather.com/weather/map/interactive/INXX0012:1?interactiveMapLayer=sat&baseMap=r&zoom=8

Taken at 2.30 pm. Appears like Kanpur, Jhansi is getting good rain.

rajesh said...

GSB: Thanks for Panchgini report..have a good trip.
Generally clouds are seen accumulating over Arabian sea only during the system approach or trough deepening...
Vikas: welcome to vagaries...We had put up rain for delhi ncr for wed..i got report of rain today..shall put up next forecast...typhoon impact is not this week, and expect some improved rains as axis moves north..
Pradeep: Thanks...i stick to my forecast put up for Tuesday..no rain yet :-))

GSB said...

Very heavy rainfall at mahab when I was there between 6.45 pm to 7.45 pm. Must be about 20_25 mm in that hour not sure, clouds dark greyish and visibility very low due to heavy fog, difficulty in driving back to panc...very light rain at panch right now...