Sunday, July 15, 2012


When we talk about weak monsoons, let us first compare this year's figures with some of the other weak monsoon deficit years.

2009 saw the lowest rainfall (all India) in several decades. End of July in 2009 was at an unbelievable deficit of -47 %. It ended up with an end of season deficit of -28%. 
For an on date comparison of 2009, see Vagaries' Blog of this date here
On this page, Please move on to 16th July (2009) write up.
Check the rainfall figures for Gujarat on this date...havn't seen such figures in years.. 

1972 was also a drought year with the season's deficit at -24%. End July was at -31% in 1972.
The worst ever for drought ever in India was in 1877 when the monsoon deficit was at an ashtonishing -29%.

Current Weather:
Last few days, TN, AP and parts of Interior Karnataka got the much needed precipitation. As Venkatesh points out, it has reduced the deficit in the region and provided the much needed moisture in the interiors.
In TN, heavy rainfall was recorded in Alangayam  (dist Vellore) 11, Paiyur AWS (dist Krishnagiri) 9 and Vaniaymbadi (dist Vellore) 9, besides many station between 3-9 cms. With some rains, Chennai AP has crossed the 100 mms mark and is at 109 mms.

In AP, Chittoor (dist Chittoor) 13, Rajahmundry (East Godavari dt) 11, Avanigadda (Krishna dt) 10, Palamner (dist Chittoor) 10, Shriramsag.pocha (dist Nizamabad) 7 and several other stations below 7 cms.

Though Karnataka interiors did not recieve such heavy rains, at Bangarpet (Kolar dt) 8, Karwar 7, Manki (Uttara Kannada dt) and Hoskote (Bangalore rural dt) 6 each. A begining has been made with rains between 1-3 cms. Bangalore city got some rains, managing 12 mms, pushing up the season's total to 27 mms.

An off shore trough extends along the Eastern Coast of india, from the "low" over the NE States (the East end of the Monsoon Axis)crossing the coast into Interior TN. The trough encouraged and aided the formation of Thunderclouds in the Interiors of the Southern States due to drop in pressures at various levels.
The susequent rainfall along the trough was not predicted by any model, and formed as a result of the Eastern end of the Monsoon axis getting strong.

Outlook:Monday 16th:
Substantially reduced rainfall in TN and Karnataka. 
S.I. Karnataka will get some showers (10-15 mms) and Interior TN west of Chennai will get precipitation upto 15 mms. 
As the off shore trough off the west coast starts strengthening along South Konkan /Goa, medium/heavy precipitation expected in the region.
West Vid could get light to medium showers in the day.

Tuesday :17th
The off shore trough along the west coast extend upto N.Konkan, while, and UAC embedded in the Eastern coast trough moves West from Chennai (inland).S.I. karnataka gets light rainfall.
Heavy rain/Thundershower in Nagpur on Tuesday night, extending into Wednesday morning.


Wednesday 18th: 
Reduction in rains in Karnataka and TN. An off shore vortex could form off the Mumbai coast on Wednesday. Stations along Konkan will get between 100-150 mms.
Precipitation upto 15 mms expected in Vidarbha on Wednesday. South Interior Mah could get rains upto 30-40 mms.

Saurashtra region does not get any meaningfull rains on these 3 days.

Rains in N.Pakistan will decrease from Tuesday.Light rains along Sindh Coast will prevail till Tuesdaywith Karachi getting light rains. 

City Forecasts for Monday16th/Tuesday17th/Wed 18th:
All City Rain Amounts 8.30am-8.30am next Day:
Mumbai: 
Monday: Cloudy morning. A couple of sharp showers in the afternoon. Passing showers in some parts in the late evening/night. Rain Amount: 20-25 mms
Tuesday: Overcast morning, with 2/3 showers in the day. Rainfall increasing by evening. Heavy rains at night. Rain Amounts: 40 mms. 
Wednesday: Cloudy day with frequent showers, at times heavy in the afternoon. Heavy rains with thunder on Wednesday night. Rain Amount: 60 mms.
Satellite Towns like Panvel and Navi Mumbai could get heavier rains on Tuesday and Wednesday, possibly crossing 100 mms on Wednesday.


Pune: Monday partly cloudy with light drizzles. 
Rainfall shows a slight increase from Tuesday, with a heavy shower expected in the evening/night.
Wednesday: Overcast cool day. Several light/mdium showers with rain amount around 20-25 mms.

Surat: Monday/Tuesday: Cloudy with a few showers in the day. Rain amounts 10 mms/day.
Wednesday: Overcast with heavy showers with thunder. Increase in rain amount to 40 mms.


Delhi/Haryana: A thundershower in some parts on Monday. Rain Amount: 5-10 mms. Tuesday/Wednesday will be almost dry and partly cloudy.

Chennai: 
Monday: Could get a shower by evening.
Tuesday: A few showers in the daytime, with rainfall amounting to 10-15 mms.
Wednesday: Cloudy with light drizzles.

Bangalore: 
Monday: Light showers possible with a cloudy day. Rain upto 10 mms.
Tuesday: Cloudy with light rains in the day.





38 comments:

Atul said...

I hope a good news for interior Maharashtra :)

Rajan Alexander said...

Rajesh - Send you the Modokai draft

Pavan said...

I think july is also dry for pune it may not cross 100mm this july and no meaningful rains til mid august monsoon showing shades of yellow nt green

GSB said...

Thane city got 19mm rain today(from 00am) taking the season's total to 813mm. This means that it has reached 1/3rd the annual rainfall of about 2400mm....

penny said...

please explain why the mjo is so weak which is affecting the southern peninsular India.

venkatesh said...

For the past 4 days Tamil Nadu,Andhra is getting good rains.Infact TN deficiency reduced from 55% to 20%.What is the reason for the sudden surge in rainfall.Infact this is applicable for Bangalore and some parts of interior Karnataka.When every one predicted Lull in SWM.It turned otherway and it produced some critical rainfall for Andhra and TN.How long this is expected to continue?

Shitij said...

Today the weather was slightly different. Between 5am to 10am Surat got some frequent showers. These showers were not prolonged. Each shower lasted only for 5-15 min. At that time I thought that offshore trough has become little bit active but after 10 am cloud cover has been reduced drastically. Weather has become completely sunny. Some high clouds were seen in the sky.

junaid said...

@rajesh plz update about the total seasons rainfall received by panvel till today !!! Nd nowadays u r not putting panvel figures on mumbai page??ny problem in retreiving data?

Abhijit Modak said...

Today Badlapur, Thane Dist got 33mm from 12am to 10pm period. Nice heavy spells through out the day. I think now from tuesday rain spells will be increasing with frequent spells all through the day for Konkan belt . And Why Tamilnadu receiving spells as if North East Monsoon is set because rains looking like coming from NE side as per sat image actual from which directions clouds coming there I don't know !

Pradeep said...

Venkatesh,

If you are watching the radar daily, you can see that http://www.imd.gov.in/section/dwr/img/ppz_chn.gif

Thunder clouds form in the month of June to September near the Karnataka/Tamilnadu border belt around 250 kms from chennai and they move SW/SE direction towards the sea.

This is daily phenomenon when monsoon is not in a break stage.

So these rains are short but very heavy in nature. When the come near the sea. It may weaken if there is a strong sea breeze.

rajesh said...

Pavan: Where is the forecast for mid Aug ??
penny: MJO is almost 'neutral' not very weak as i have mentioned several times in last week's post.It is in waves, alternating between strong and weak phase, we are lucky to have a phase almost neutral now.
junaid: no difficulty..put up on Mumbai page..there was no response from my query so imagined you were away..anonymous also asked for them..

Pradeep said...

Tamil Nadu got battered for 3rd straight day.

see the daily graph

http://www.imdchennai.gov.in/hydro.gif

From deficient rainfall to normal rainfall in 3 days is awesome.

Yesterday the rainfall was more widespread.The coastal and delta areas got good rains.

The trend seems to continue till next week.


All is well for SWM for TN this year

Mithun said...

Hi Rajesh

Nice Blog, please update if the rains will be good to hold on till september in maharashtra and north karnataka ?

svt said...

@Rajesh, Your forecast for yesterday was almost spot on. Dadar had 2 sharp showers in the evening.. one lasting 5 mins, the other 20 mins. So function gone well without any hiccups. Thanks. :) I think this week gonna be wettest week of this season so far.

Vivek said...

Just as feedback. No rain in Gurgaon/Delhi today. It was mostly sunny.

Thanks,

Anonymous said...

Congrats on reaching 200 thousand visits :)

Regards, Ananth

sset said...

Last myself and relatives visited Malsej ghat, morbat. Place is extremely beautiful - dense forests, water falls cascading at all angles, clouds touching ground, dense green paddy fields - simply looks like painted figures- my wish leave my job in Bangalore and spend my days here amoung hills. Entire drive from Navi Mumbai - Kharghar- Taloja- Kalyan - Morbad - Malsej ghat was breath taking and non-stop torrential rains!!!!

Today I am back to Bangalore - same traffic, water problem - no rain - only 1 drop!!!! No rain water harvesting will work as there is no rain.

sset said...

Bangalore mirror says - 10mm of rain in 24hours - is too much!!!!!!

Wonder whoever has written this - has ever visited Mumbai or Chrapujii-> rains are measure in cms or meters - any thing less than 100mm is just normal light rain for Mumbai people.

Vivek said...

Wrote too soon! 5mm of rain in Gurgaon just now.

Congrats on 200k!

Anonymous said...

no rain today & i don't see much rain even in the evening,hoping things would change

Abhijit Modak said...

@ sset. yaa.. actually as per local geographic conditions their , so local people also are use to it from many years ! As Bangalore monthly average is just 100mm so if daily 10mm fallen then average cross in just 10 days ! So all will say excess rains now or this time too much rains ! Even if u take Pune peoples or Pune newspapers, they will say 40mm in 24 hrs are heavy rains for them ! As they know just drizzles ! And 40mm on daily basis is not seen at regular basis !so as rarerly seen, so 40mm is considered heavy in Pune! So mindset is set as per local geographic condition !

sset said...

GSB - last 3-4 years Mumbai rain exceeded its normal averge of 2500mm -infact it comes around 3500mm - 3800mm.

Ron said...

news channels are quoting met as saying that monsoon will be deficient in july,august,september...

Pavan said...

@sset i do nt know y u do not understand the geography of interior peninsula, if it rains like c'punjee or mumbai here the there will be minimum 200 deaths, u may be knowing when cyclone hits these areas the it rains the most may be max 40cm recent was in kurnool in june 2007, and in oct 2009 there was heavy loss of life and property it is is the normal for arid and semi arid

Anonymous said...

holy balls,what has happened to this blog,pls revert back to the old style,it looks highly cluttered,its also confusing.Didn't like the new look

GSB said...

@SSET, tomorrow I might do some analysis of Mumbai rainfall for the past 50 years. Meanwhile total monsoon all India as on today is 243mm. Required in the balance 76 days is as follows..

16/7/2012 243mm

to achieve min700mm 6.0mm per day
to acheive avg900mm 8.6mm p/d
to acheive max1100mm 11.3mm p/d

current runrate (err rainfall rate!!) is 5.28 mm p/d

I'll be putting up these figures every few days....

GSB said...

I don't know if this is permanent @Rajesh sir but all the fans can select CLASSIC view for some familiarity on the blog...

junaid said...

@rajesh plz update abt the total seasonal rainfall till date for panvel !!!!iwas keeping a tab of the figures ,,but in between i lost touch(expecting between 80 - 100cm)!!!one more thing i wanted to say u i cleared my f.e atkts and got 64%in 4th sem!!!:):):),,so now promoted to 3rd year!!

Ron said...

i am having to click on view comments a dozen times before it opens up..is anyone else facing this issue...

sset said...

GSB - so you are doing regression analysis - good estimates.

rajesh said...

thanks everyone...
vivek: iwas it as per forecast ?

Junaid: Congrats to you for your good scoring...best of luck and always wish you well for your future studies...reward for your good marks..Panvel total is 822 mms.
GSB: Thane total 858 mms.
mithun: thanks..cannot tell for aug.sept from now...only observing the MJO and El-Nino now...

Pavan said...

Congrats junaid hope ur marks and rainfall of panvel are directly propnl to each other

Abhijit Modak said...

@ Rajesh Sir. Blog's background image which you have putted with sea & above line type clouds with blue sky and yellow & reddish shade, that Exactly same shade was seen yesterday 7pm at Badlapur also.But IMD Satellite image & Wunder ground were showing thick cloud cover over the region so I asked the doubt on vagaries of the weather FB Group that why such variation in actual ! And our region Badlapur in the foot of Matheran range and Western ghat also starts on 30kms range from here, so were experiencing daily rains amounting in 20 to 40mm range. So Please provide the Barvi dam belt rainfall figure too till today. I think it must be nearing to 1000mm mark now !

Vijayanand said...

Back in bangalore after 10 days in mumbai. Except for early part of last week, it wasn't too wet. BUt every morning between 8.00 am to 9.00 am w/o fail we got heavy rain for 5 to 10 min. By weekend thw climate in mumbai was terrible. Warm and humid.
Back in bangalore now. Its cold and cloudy. Apeears like it rained a bit in my absence :)

Vijayanand said...

Guess its gonna rain heavily in mumbai this week. Bad luck missed rains by a week :(

Abhijit Modak said...

Thundery heavy rain spell just now at Badlapur here. 15mins produced 7mm rain.Thick Black Formation was formed over WWN side.

NT said...

Continuous medium / light rain since the last 1.5 hrs at Andheri. It's got very overcast and dark currently.

Looks like a very rainy patch is about to start for Mumbai, as per the COLA images the weekend too looks like a washout.

rajesh said...

NT: 44 mms at scruz and 25 at clb..vagaries' forecast 40 mms till wed morning...
forecast same as put up..no change.