Friday's Rains in Delhi. West UP and HP..were WD Rains...Why?..See Current Weather Page 

Severe Cyclone "Phailin" Update as on 10.30 am IST:

"Phailin"is something to be carefull of !. The storm is rapidly intensifying, and now at Cat 4, is having core pressure of 930 mb and estimated sustained core winds of 250 kmph !!
Location: 16N and 88.5E.

The current eye is warm, and almost 80c warmer than the outer bands. Current central clouds are at -6c, compared to -86c in the outer bands. The outer wall, has shrunk, and is seen almost consuming the original eye. So, temporarily, the intensification may halt for the next 6hrs..and may even weaken a bit. But, if a perfect new eye forms, the intensification can resume again.

Tracking at 15 kms/hour, in a NW direction, and seeing it is 530 kms from Paradip (SSE), Kalingapatnam (ESE) and Gopalpur (SE), we can calculate its landfall in another 36 hrs from 005hrs IST (Friday). This calculated to Saturday evening. 
That means, the outer storms will take effect on the coast from Saturday morning .

Alert warnings to North AP and Odisha coastline of strongest winds at 135-250 kmph, which are destructive. Please adhere to local warnings issued by govt. authorities.

Severe Cyclone "Phailin"  Cat 3: (10.30 pm IST)

"Phailin", getting stronger by the hour, has reached a stage of Rapid Intensification. The Intensity which was 4.0 at 0000Z has rsen to 6.0 by 1200Z. 
And that is tremendous !
With an well formed eye, 15 kms in diameter, it is but obvious that the central uprising warm air is turbulent, and at the "warm eye" the cloud temperatures in the centre of the system has risen to 0c, while the outer cloud top temperatures are imaged at -80c.

Wind speeds and core pressure indicate a Cat 3 status...Winds around the eye are estimated  at 185 kmph (though DVORAK calculates at 212 kmph). Core pressure is sliding down at astounding speed, is currently estimated at 949 mb.

Now, with core winds of 185 kmph, if the upward warm current mentioned is strong, an outer eye , a circle of severe thunder storms, can form, and "choke " the original eye. In this phase, the cyclone weakens. But, generally, an outer ring can form if the original eye is less than 10 kms in diameter.
Can only re -strengthen if the inner wall is completely wiped out by the stronger outer eye.
But all this can be superbly observed  by a reconnaissance aircraft. 

Located now at 15.5N and 89.5E...
Tracking NW, "Phailin" will move towards the AP/Odisha border. Srikakulam, Vizianagram and Vizag District (AP) should be seriously alerted. And Gajapati and Ganjam Districts of Orissa should be alerted.

Next Report Friday 10 am IST
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Severe Cyclone "Phailin": Cat 1: As on 1 pm IST Thursday.

Location: 15N and 90.5E..Track NW towards North AP coast.
Central core estimated pressure :  980 mb..Eye clearly Formed !
Core Winds..120 kmph !!. Cat 1  .... Cloud Temperature falls to -80c. Vertical shear mild "brushing" seen. But immediate intensification to Cat 2 seen within 12 hrs with winds expected to cross 150 kmph.

A possibility of intensity decreasing slightly before landfall...But still could be severe. Just a possibility.

Conditions and parameters have become favourable to exit the SW Monsoon from further regions in North and NW India. 
What we see are parameters like the OLR and UTH going the "non monsoon" way. The water vapour image also points out to reduced seasonal moisture from the region. This is due to the high pressure in the 850 hp zone moving in rapidly from the west.
Monsoon Axis has shifted down south. If the East wind blowing in the Notrthern plain is shown as the only parameter showing "pro monsoon" condition, let me clarify that the East winds are not from Bay but from far east (Myanmar).

So, according to Vagaries, the SWM has withdrawn from Haryana, Delhi and West UP regions. See Map.

This is the longest SWM tenure in Delhi, beating the previous IMD record of 111 days in 1956. But, to compare, we wait for the IMD withdrawal date.In 1956, the SWM withdrew from Delhi on 13th October.
The post Monsoon type of clouding was reported from Delhi on Wednesday 9th..Stratocumulus not resulting from the spreading out of Cumulus
Altocumulus, the greater part of which is semitransparent; the various elements of the cloud change only slowly and are all at a single level
No Cirrus, Cirrocumulus or Cirrostratus

A WD is moving in from the West, so we can expect South winds in NCR by Thursday or Friday. Light rains expected in some parts on Thursday or Friday.

BB-15, 02B  latest Below in previous Post v
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BB-15, 02B, as on 9PM IST Wednesday: Deep Depression heading to Cyclonic Storm...

Location: 13.9N and 92E. Winds :  90 kmph    Core Pressure:  997 mb  Cloud top Temperature at Centre:  -65c  Outer cloud temperature:  :-61c
Track Expected to continue NW towards the AP/Odisha coast. Very favourable Equatorial flow will produce extreme rains in SW and S quadrant. Wind shear minimal now.

Warning: As the  system moves, it will intensify into a cyclone by Wednesday Night/Thursday morning. Very heavy rains likely to commence on the Odisha and North AP coast from Friday. very squally and damaging gusty winds that could go up to 150 kmph along the coast at time of landfall. Landfall as of now expected around Saturday,12th October. 


Heavy rains expected along W.Bengal coast on Thursday evening onwards.

Another Posting of SWM withdrawal from Delhi tonite by 11 pm IST..

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1. BB-15 Report at 1 pm IST Wednesday:

BB-15,(02B), a deep Depression, is located at 13N and 93.5 E, thus having tracked NW. Current location is 170 kms N/NE of Port Blair.
Core pressure is estimated at 1000 mb, and is of T2.0 intense. Core central winds are estimated at 60 -65 kmph, but gusting to 80 kmph.
Cloud heights have increased due to force convection, and cloud tops are at -80c.
Favoured conditions show NW track to continue and head towards Odisha..

Next Report at 9 pm IST with map of track and estimated areas of possible effected regions and heavy rains.

2. Axis runs from Gujarat thru Chattisgarh and into BB-15. Embedded UAC over Gujarat and Chattisgarh, almost forming an upper trough parallele to sea level trough.


All parameters (barring 1) favour a SWM Withdrawal from Haryana and Delhi regions, West UP.....more in Note tonite..

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Conditions favourable for SWM withdrawal from Delhi region by Wednesday or Thursday..shall put up note here on Wednesday....

BB-15 report at 10 pm IST:
Since last Vagaries' report at 1.30 pm IST, Depression BB-15 has moved to location 12N 94.5E, that is due westwards. In  hrs system has moved 100 kms , and is T 1.5 strength, 1003 mb..Core winds at 35-45 kmph and clouds higher in height having top temperatures of -80c.
The vertical wind shear (resistence) has decreased even more, and is between 5-15 knts.
BB-15 will graduate to Deep Depresion tomorrow (Wednesday).

Track will be NW, and cross the Andaman Island chain North of Port Blair. Though, the S and SW quadrant are showing very intense clouding and heavy rains over the Islands.
Port Blair recorded 91 mms till 830 am IST on Tuesday and 43 mms on Tuesda till 5.30 pm.
Karthik Narayan informs of massive rains from Andaman Islands: Mayabandar -25cm... Long Island-24 cm from 8 30 AM to 5 30PM today...

Chennai can get some showers form the "outer bands" when the system is en- route to the coast. That calculates to some gusty showers on Thursday/Friday. (All calculations on Current situation and position).

BB-15 Report at 1.30 pm IST:
BB-15 ( Depression): slight deeper, at 1002 mb, than our 10pm IST report. Having moved to 12N and 96E, it has shown a W/NW directional movement by about 90 kms. Now, having to encounter 20 kts vertical wind shear, which is less than its previous position, it can show tendency to get deeper soon. Current cloud top Temperatures are -70c.  Core winds at 35-45 kmph, it is showing convective band formation at SW of core. Band convergence in SE is taking shape.
Track expected NW. 

Next report on BB-15 at 9 pm IST. 

Posted on Monday @ 10 pm IST

BB-15. As a low pressure area at 1006 mb, has entered the Bay waters. On latest evaluation  it is located at 11.5N and 97.5E. Winds at core are 15 knts. 

Clouds convergence seen building around centre. Though organised bands are still not prominent.
However, some wind shear is seen near the system, and prominent shear is seen in the mid levels.

Seeing the other factors, the system would move N/NW initially, and maintain strength at 1002/1004 mb. Later, it can curve NW around 14N, and track towards Odisha/Bengal coast.

In the previous article, we had mentioned about the Monsoon axis slidig towards Central India. The axis has placed itself in the central India region. 

Now, we wait for the next development: the UAC formation in the axis ! I estimate the formation of a UAC around MP, and head....west !

Rohit's Page just Uploaded with very interesting Details of Mumbai-Pune region rainfall for this Monsoon...Very Imaginative Diagrams...See Rohit's Page..

See rare Arcus clouds formation over South Mumbai on Friday evening..Mumbai Page
A Typical Image of a 2 day "mini break Monsoon" scene mentioned yesterday*, with Cb clouds popping up at random in Central regions...

Posted Saturday Night 5th October:
The Arabian Sea UAC off the Goa/S.Konkan coast effect is seen with these rainfall figures (in cms) as on Saturday Morning: 
The Rainfall was very heavy, as seen from amounts sent by Pradeep John and available on his Page.
Besides, Abhijit has put some amounts of today's rainfall in the comments also.

Besides, very heavy rainfall of 201 mms in Allahbad and 89 mms in Jhansi and 59 in Varanasi, was the effect of BB-14 floating Northwards.

Delhi was cool and cloudy with the day's high of 26c being at 8c below normal at Palam and S'Jung. But several spots like Lodhi Road, University and Ayanagar were at 25c. Faridabad too was 25c.
Delhi NCR may just get the shower in pats on Sunday 6th. Rainfall decreasing from Monday.
Some models show the UAC from central axis spilling some rains in Delhi and North MP areas from later next week. But it depends on the UAC position and stregnth, so we will monitor the system after it forms. Otherwise, call for withdrawal !

*BB-14,now in the foothills, will create a mini "break Monsoon" in central India and interior peninsula. But only till Tuesday 8th.
The axis on Tuesday "frees itself" and moves into the central India area, in the Gujarat/MP/Chattisgarh line.

But, it is very possible  that an UAC may form in the axis in the Southern MP region by Tuesday or Wednesday.
Hence, after subdued rainfall in the NW and Central India and interor peninsula  on Sunday /Monday, rains increase in MP and North interior Maharashtra again from Tuesday.

Surat and Bharuch, wait for the UAC in Central India to form, and get the rainfall increasing from Tuesday 8th and Wednesday 9th.

A low pressure forms in the Andaman region by Monday, 7th October. Seeing the present winds and upper jet streams, i would expect the system to track NW towards the AP/Odisha coast. Should be at least of Depression strength on reaching the coast by the 13/14th October.

The west coast trough weakening after the UAC has crossed the Goa coast, should spell well for Chennai. City may see an increase in its thunder showers activity from Tuesday and continue in the week.
However, the winds would remain W/SW. We will wait for the axis to slide down and track the outcome of the low/depression coming next week to determine the date of the NEM. Generally set in not before 19th/20th at least.

Parts of Mumbai had some thunder showers on Saturday. Bhandup 37 mms, Borivali 36 mms, Kandivali measured 14 mms, Mulund 12 mms, Dharavi 10 mms, Dadar 7 mms, 

Mumbai will be warm and partly cloudy with sunny spells on Sunday. Thunder developments possible in some parts. Northern and Eastern outer townships can get a thunder shower.
Monday and Tuesday will see mild thunder showers in parts of city in the evening. Heavier showers in Northern and Eastern outer townships.
Pune may get the thundery developments on Sunday/Monday/Tuesday with the thunder shower in some parts by evening.

As we anticipate an UAC in Central India, Monsoon remains in Mumbai/Pune throughout next week.

And oh yes ! Kolkata, just continue with your Thunder showers popping up in parts of city, some severe till Wednesday at least !
Very detailed and specific account of the Goa SWM season here on Weather in Goa blog. 

Karachi has been hot and sizzlng at 40c. Though Saturday and Sunday may see some relief of a few degrees, the North winds will bring very hot conditions to Karachi next week again.

For Kathmandu, October has started of rainy and cool. With 17 mms already measured, the capital has next week too, for thunder showers are expected to form for the next 4/5 days at least. Nights will be around 16/17c though. Neeraj will tell us of the latest.

2nd Part of NEM Watch ( Advance Parameters)  published on Current Weather Page

Posted on Thursday Afternoon: 

UAC in the West Coast trough is located about 210 kms SW of Mumbai. 
The jet stream Divergence ( UWD) and shear factor have created intense convection in the South and SW quadrant.

Expected to deepen a bit over current location.
Precipitation expected on Thursday over South Konkan and Goa. Heavy at times with gusty winds from SW.
Mumbai will be windy from the S/SE direction. Showers expected by Thursday evening and increasing towards Friday. 

BB-14 has moved North from Vidarbh, and may fizzle out in next 24 hrs over MP/South UP.

Vagaries' Monsoon Contest Results !  Congratulations to the winners, for winning a very tough and Challenging Contest. Forecasting skills and meteorology knowledge at its best !
1st Place...Kartik Raghavan
2nd Place..Junaid
3rd Place...S.Subramanian, Arpit S, Salil K, Puneet B. (all Joint 3rd.)
Congratulations and Thank You to all the Participants also !

See Details of Results on Monsoon Contest Result Page...
Thane District Overall SWM Rainfall for 2013 compiled by Puneet Bangera...on Stats and Analysis Page 

and Indian State Capitals SWM Rainfall for 2013 on Rohit's Page...

Posted Tuesday 1st October Night:

BB-14 now lies over Orissa, and expected to move N/NW into Madhya Pradesh. It should linger around the Northern MP region till Thursday 3rd October. 
After Friday 4th October, it is expected to fizzle out and float cloudiness in the Northern MP and adjoining Western and South Western UP region on Thursday/Friday. Of-course, a detailed forecast will follow.

Mumbai will see the same pattern of passing showers till Thursday. A heavy thunderstorm likely on Thursday or Friday. Maybe the penultimate storm ?? Seeing withdrawal next week.
Pune can also get a thunder shower on Friday.

Light showers in several parts of NCR will prevail till Thursday, before seeing a decrease thereafter.. 
Kolkata sees a continuation of thunder showers till Friday..

Meanwhile, till Friday, the Southern Part of East coast (AP and TN) remain in a high pressure zone.
Chennai: Likelyhood of a good thunder shower on Wednesday.

As no other low is expected till Sunday 7th, in the Bay, we can see a re-withdrawal of SWM from Rajasthan and adjoining regional states after Thursday, 3rd October.

A note on North -East Monsoon, 1st in a series of 2, published on the Current Weather Page ...