Friday, September 14, 2012


As on Friday evening, the Monsoon axis is nestled in the Himalayan foothills, running thru from Pakistan Punjab in the west thru North UP and then thru North Bengal into the Bay.

Saturday/Sunday: Resultantly, rainfall will occur in Pakistan Punjab, Indian Punjab and Haryana, Delhi NCR, North UP and in Nepal. 
Hill states of HP and Utteranchal will also continue to get heavy rains. Heavy rainfall in Himalayan Bengal, Sikkim and Meghalaya.
Rainfall will be weak in Gujarat, Central India, West coast (including Konkan) and Southern Peninsula.

Mumbai City: 
Saturday,15th: After Friday overnight moderate rains, Saturday will become Partly cloudy with sunny intervals. A couple of showers , brief but heavy in some parts. Rain amount: 15 mms.

Sunday, 16th: Warm Sunny day. Day around 30/31c. Passing clouds will result in a few showers amounting to 10 mms.

Pune: Saturday/Sunday: Days progessively getting cloudy by evening. Light rains in some parts. Nights could drop to 19/20c.

Weather Analysis:

SST drops 0.1c in Nino 4 !The Oceanic Nino Index is still hovering around 0.1c. 

{El Niño: characterized by a positive ONI greater than or equal to +0.5°C.
La Niña: characterized by a negative ONI less than or equal to  -0.5°C.
By historical standards, to be classified as a full-fledged El Niño or La Niña episode, these thresholds must be exceeded for a period of at least 5 consecutive overlapping 3-month seasons}.

So, we have Neutral ENSO conditions, supported by neutral value SOI. Soi latest value is +0.8.

On the MJO front, an active wave is now moving towards the East. The MJO in our seas will see a weak phase from the 15th of September, as the current OLR charts show of the scene already getting weak in the sub-continent and moving East rapidly.

From next week, we keep a watch on the signs, if any, for the SWM withdrawal. Initially, we start , by keeping a watch on the Western Rajasthan and Sindh region of Pakistan. 

Track the pressure over the region, currently at 998 mb, For that is the first sign of the seasonal low weakening. We also keep track on the day and night temperatures in that region, for the days will riase corresponding with a fall in night temperatures. And of-course the daily rainfall.

On the charts, we observe and see if an anti-cyclone develops in the region. 
These are some of the indications to keep an eye on (besides many others), as these will give us the pointers to the withdrawal commencment. There are no indications yet !

My estimate is that the withdrawal (from Sindh) would commence around Thursday, 20th September.  

51 comments:

Anonymous said...

heavy rains in vasai very windy too at the moment.

Arpit Sharma said...

Thnx sir for the report

Anonymous said...

Mr rajesh thanks for the feedback

Anonymous said...

heavy rains are going on in vasai

rajesh said...

NT: seems Ganesh Chaturthi on Wednesday will be quite sunny and warm. Passing showers in different parts. Nothing very disruptive.

Anonymous: Thanks for vasai report..please put ur name too.

prakash:Mumbai will get rains as long as monsoon is still on..we have the heavy thundershowers still to come..

Anonymous said...

thanks rajesh sir . for mumbai report


prakash


Abhijit Modak said...

@ Rajesh Sir. Very nice explanation.. Helping me for learning weather. Yes Mumbai & mainland suburbs get North Easterly / Easterly thunderstorm rains in evening/night period with day very hot, temp touching almost to 35 C.. with huge lightening strike & some time very heavy around 70 to 120mm also in just 3hrs rains and mostly occurs from Ganpati festival ending period to Navaratri/Dasara..

sset said...

Last year Mumbai had rains till deepavali - big bang thunders - 3700mm rain total sharp @ 4pm.

Anonymous said...

What is the highest annual rainfall ever recorded in mumbai and delhi?

Pradeep said...

Preliminary rainfall in mm till 8.30 am on 15.09.12 from Twin Veppasalanam Storms in Chennai…..Its so humid in the morning itself….expect more storms today

Chennai AP – 42
Kolapakkam near AP- 40
Ennore – 39
Puzhal – 36
Tiruvallur – 36
Guindy – 33
Marina Beach – 31
Chennai – 27
Nungambakkam Kea – 27
Poondi Agro – 27
RK Pet – 27
Chemberabakkam – 27
Katupakkam – 24
Kelambakkam – 20
Sholinganallur – 20
Sholinghur – 19
Avadi – 18
Ellapuram – 18
Taramani – 17
Poondi Lake – 16
Kadambathur – 15
Tamaraipakkam – 14
Poonamalle – 13
Uthukottai (Entry Point) – 12
Korattur Anicut – 10
Madhavaram – 10
Redhills – 10

Abhijit Modak said...

Yesterday Badlapur had an cloudy & overcast conditions and passing showers to heavy showers at times and then today early morning 4am period also had an heavy rain spell.

So overall Badlapur records 23mms rain in past 24hrs.(i.e from yesterday 8.30am to today 8.30am on 15-09-2012).

Arpit Sharma said...

Minimum temperature recorded at Delhi S'jng is 24.8c showing signs of monsoon withdrawal.

svt said...

Seems like Mumbai will not get much more than 50 mm of rains for rest of theseptember. October in last 2-3 years have been good in heavy thunderstorms wise. So fingers crossed.

Arpit Sharma said...

@ Rajesh sir
Many sites including IMD is showing 18sep as the last day of monsoon rainfall for delhi-NCR.Is it true?

Anonymous said...

monsoon will withdraw from delhi on 19th sept , weather will be completely dry

Arpit Sharma said...

Raining moderately in Ghaziabad from the past 10 minutes.

Anonymous said...

@svt, its true that mumbai has been experiencing very heavy thunderstorms for past 3 years in october, but this this year chances r faint , but lets keep fingers crossed as things can change rapidly. n we can have those thunderstorms this year too.specially if the october humidity goes too high then we will definitely have those thunderstorm in mumbai.


thanks prakash

Anonymous said...

@anonymous
the highest annual rains for mumbai is 3700 mms till date where as for delhi its 820 mms.

Arpit Sharma said...

Data is not correct for delhi as delhi has received more than 1000mm rainfall in 2010.

Arpit Sharma said...

Rained moderately,then sun came out,now raining heavily.

RK said...

very heavy rains right now at G.Noida

Arpit Sharma said...

Now sun shining brightly here in Ghaziabad,seems that small thundercells are causing these spells of rain.

RK said...

@Arpit, yes...this seems to be scattered rains...sun is shining here too now :)

rajesh said...

Arprit/RK: Radar shows medium sized thich clouds scattered in the SW/S/SE of Delhi. A big one in the eastern region..
difficult to say the last day in Delhi now, but i think will extend surely beyond 18th..i see a weak UAC in the Bay on the 18th.

Prakash/SVT:as yet it seems we in Mumbai will get the parting thundershowers. the vertical lift may be favourable, and it seems that the thundershowers could start after the 25th...time period will depend on the speed of the other parameters of withdrawal..

rajesh said...

anonymous:Mumbai highest annual total is 3481 mms (1954) at colaba and scruz 3785 mms (1958). Delhi highest annual rainfall is 1533 mms (1933) at S'jung and 1306 mms (1967)at Palam.
Request all to please sign in your names..i DO NOT like answering to "anonymous"
While putting in your views PLEASE sign your name as well .

Abhijit Modak said...

Very nice sudden change in weather here in Badlapur. At 1pm temp was 30d C with bright sunshine.. From 2pm sky started to get overcast from WSW direction with spray showers in between. Now at 3pm full dark sky with medium to heavy rains with strong gusty winds from WSW. And temp drop to 24 C now. Feeling very awesome & chilly now so fans are turn off at home .

Abhijit Modak said...

Actually such afternoon spell in Badlapur are noticed on daily basis but temp would come down to 26 C while spell is on but today it has came further down to 24 C. So really enjoying & loving more such weather conditions.

Abhijit Modak said...

Now rain has stopped here. But thunder sounds are heard here in North direction.

Abhijit Modak said...

Now thunder sound also stopped here in Badlapur. Temp raised to 27 C now. 16mm rain measured here for last 1hr spell.

Arpit Sharma said...

Again some clouds are appoaching,might bring rain in the next couple of hours.

Vivek said...

Sir raining now in Gurgaon. Some lightening and thunder before it started raining.

Arpit Sharma said...

Lightening here in the west direction.

GSB said...

Again this week so far all six days starting Monday have been above normal. Yesterday (ending 8.30am today) Punjab received 14.8mm against 2.3mm ahich is 543% above normal. It's seasonal deficit is now at 50%.

Other notable subdivisions..

SHWB & Sikkim +423%
BIHAR +442%
A&N ISLAND +697%

ALl India deficit stands at 7%.

Arpit Sharma said...

Raining lightly here in Ghaziabad with lightening and thunder,can turn into a heavy shower at any time.

RK said...

thundery and windy with light rain here at G.Noida

Neeraj said...

Sept average and yearly average exceeded; its raining like anything here at Kathmandu, Nepal.

Anonymous said...

HEAVY SHOWERS HERE AT VASAI.

Abhijit Modak said...

Yesterday Badlapur had an heavy spell in afternoon period which cooled an weather here and today early morning around 3am also had an heavy spell.

So overall Badlapur records 30mms rain in past 24hrs.(i.e from yesterday 8.30am to today 8.30am on 16-09-2012).

sset said...

Bangalore day 16 sept NO RAIN. This must be driest september/worst drought ever recorded. Total rain since june 260mm. Mysore/Mandya...still worst.

pavan said...

travelling in south between kar mah border from last one week dry weather with clear cool morning and muggy cloudy thunder in the eve but no rain today going still south towards belgaum hubli, drizzling heavily now 20km north of belgaum heavy clouds coming from sw, today i wll be in queen of braganza ghat castlerock

Vikas(Gurgaon) said...

Heavy rains with severe thunder/lightening lashed gurgaon late evening yesterday. The heavy showers were intermittent but rain continued for a long time.

Arpit Sharma said...

Light to moderate rain continued in the night upto 3am accompanied with lightening and thunder.Now sky is partly cloudy and might be there another thunderstorm towards late afternoon/evening.

pavan said...

sir, r there any chances of bay low moving towards ne/wb/bangladesn

Ron said...

Rajesh sir:- wanted your views on the uttarakhand cloudburst...was it really a cloudburst or is the media mis interpreting it??Wasnt it already anticipated because of the monsoon axis shifting northwards to the hills...

Arpit Sharma said...

Partly cloudy weather here in Ghaziabad but chances of rain are very bleak.

Vivek said...

Sunny here in Gurgaon. Let's hope it does rain.

Vivek

rajesh said...

Ron: I would not call it a cloudburst. Though not official, a cloudburst is when torrential rains fall in a period, maybe upto 150-200 mms/hr. But here, i checked up the rain records, and see on the 2 days mentioned rainfall ranging between 100-150 mms in 24 hrs, Thats ok..for heavy rains. Musorrie recieved 91 mms in 24 hrs.
Would not say its unexpected when it was specifically mentioned and forecasted as heavy rains in Utteranchal (vagaries even mentioned the "hill states") for Thursday/Friday.And anyway , Ron, as you say , when it was stressed that that the axis is moving north towards the Himalayan foothills, it was expected.

Pavan: Yes, a system may move in that direction in the coming week...i'll mention it in my late Sunday article today.

Arprit/Vivek: Dont think Sunady evening now will bring any rains ...

Anonymous said...

rajesh sir , are there any possibilities of any circulation to develop in the arabian sea this year as the monsoon withdrawal period starts by next week.


prakash.

rajesh said...

prakash:As yet, during september i see no possibility, and do not think so for early october seeing the weak MJO...but...

Arprit/Vivek/RK: Raonfall in Delhi NCR till Sunday morning. Bhiwani 100 mms, Nurnaul 70 mms,Faridabad 40 mms, Palam 34 mms, Ayanagar 32 mms,Mungeshpur and Ridge 27 mms, S'Jung 24 mms,Gurgaon and Lodhi 17 mms. Narela 8 mms and Indirapuram 7 mms.

Arpit Sharma said...

Yes sir,chances are very less for rain today but what is the forecast for next couple of days?

GSB said...
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