Sunday, July 31, 2011

The all India SWM performance for 2011 as of end July is seen in this IMD map. Overall departure for the season is -4%. Corresponding Overall departure as of end July in 2010 was -5%, and in 2009 it was -19%.

For Maharashtra, Vidharbh region is the most deficit with -14%.
Gujarat is lagging behind this year. With East Gujarat region showing a deficit of -40%.Kutch is dry, with having received only 16% of its required normal seasonal rain. Lakhpat town in Kutch has received only 6 mms till end July Season's normal for this town is 360 mms.. Abdassa has totalled 22 mms.

Mumbai Page updated with July amounts and Sunday rain figures.

Defying odds, UAC lingers on and expands on Saturday night off the west coast. Much against expectations !
strengthening the trough and precipitating very heavy rain on Saturday night in and around the Konkan.
Colaba recorded 147 mms in the night, and S'Cruz 120 mms. Both figures are for 8.30 pm Satrurday to 8.30 am Sunday.
And seems the vortex is still maintained at -30 as on noon Sunday... Analysis done on personal level indicates creation of wind shear, within a short span of 6 hrs, of upto 40 knts , created unstability in the atmosphere. This has occured from south Gujarat to Karnataka coast. Promising heavy rains all along with very heavy 6 hrs.

Saturday, July 30, 2011

For Mumbaites interested…Mumbai Page just up dated with Sunday/Monday forecast.

31 cms in Panvel, 25 cms in Thane...and 20 cms for 24 hrs...that heavy rain for Konkan !! Updating forecast tonite.

via gmail

Friday, July 29, 2011

See Mumbai page for Rainfall

JU-2 has precipitated good rainfall in H.P, Utterkhand. Some of the heaviest falls in H.P.was in Dharamsala with 12 cms and Chamoli in Utterkhand notching up 11 cms today (Friday), with Mussoorie measuring 15 cms yesterday and 8 cms on Friday.In Punjab, Amritsar came up with 7 cms.

Meanwhile, the Konkan downpour came up as expected. Amongst the heaviest was Uran, east of Mumbai with 19 cms as on Friday morning. Dapoli and Ratnagiri had 15 cms. Mumbai figures on Mumbai Page.

The monsoon axis hangs along the normal position, and the UAC in the SE bay persisits. The monsoon axis runs from Rajasthan thru M.P. and then branches off to the NE states. Another branch from M.P. runs SE into the Bay. This double branching is quite common and not unusual. UAC over Saurashtra has vanished.
Off shore trough shows a vortex at 700 mb level off Karnatak coast, and as anticipated, runs along the coast till Karnataka. The vortex, strengthening, would bring heavy downpours to the Konkan, Karnatak coast and Goa on Saturday. N.I.Karnatak, would get some heavy rain on Saturday.

Due to this, expect some rainfall, say up to 40 mms , to move up the south Gujarat coast and bring some rainfall into Surat on Saturday. Bharuch can expect a few showers too on Saturday.Probility of rain decreasing by Sunday in the region. Decreased rain in rest of Gujarat for the next few days.

No possibility of any meaningfull rains in Sindh or Karachi till an organised system crops up. Maybe an odd "un-organised " shower. North Pakistan rainfall continues due to JU-2, with Risalpur notching up 98 mms and Lahore 39 mms, Islamabad had 33 mms. Karachi had an odd shower, as per our reader Tyrone quite heavy in his area. But station measured traces of rain. Rainfall decreasing in N.Pakistan from Saturday as JU-2 moves eastwards.

Rainfall has also moved into central Nepal. Kathmandu received a good 39 mms on Friday, July Rainfall (till 29th) = 412.6 MM, which is +15.74% of average (till 29th, still two more days to go). Keeping the day pleasant at 26c. Rainfall to ease a bit after Saturday.

Nagpur has received 140 mms in June, and 210 mms of rain in July ( 10 actual rainy days in July), as yet, with the seasonal total reading 350 mms, which is 103 mms below normal, -23%.

Lowest rainfall in Vid is at Wardha, which has measured up only 265 mms till 29th, 178 mms below normal.That is -41%.

Absence of direct systems from the bay could be the reason for deficient rains in Vidharbh.

Mumbai/Pune forecast for Saturday valid as put up yesterday.

New forecast for Sunday onwards will be put up tomorrow. Performance of Monsoon up to July end will be up on Sunday.

Thursday, July 28, 2011

As on Thursday morning, the monsoon trough is seen placed in its normal position. And, the MJO seems to be accomodative, postponing its supressed stage by a week. So, we go and chase up the scenario (2) discussed on 25th July.

Reproducing the scene of 25th for convienance: "
-"2. In case of MJO showing no weakness and remains active (at least till this coming week):
a) Monsoon axis remains along current line, with normal precipitation along its length. West coast trough can fluctuate from weak to strong. Southern Sindh coast showers may linger along coast for a couple of days into the week. Western Nepal continues to get rainfall.
b) An UAC can form in the bay and move inland towards the end of the week (27th/28th).
c) Another weaker UAC, seen forming in the in the southern Bay, can form and bring some precipitation into T.N."

And where are we vis-a-vis this projected today ?
a) Monsoon axis is back very dutifully in line again, west coast trough showing its moods, flucuating between yes and no. Southern Pakistan coastal rainfall has diminished though.
Nepal rains continue, with an increase expected on Friday, specially in the Kathmandu (central) region.
b) UAC has formed in the SW Bay, and remains off the coast as on Thursday morning. Do not think another UAC will form (as anticipated), but the current one can become a low (BB5) and move inland in another two days.

As anticipated, rainfall along the U.P./Delhi corridor has increased, with Delhi measuring 58 mms of rain in 24 hrs. Some heavier rainfall spots were also recorded in U.P.
Monsoon rains along the axis was good, in Rajasthan Jodhpur measuring up 32 mms and Dehra Dun 119 mms.

Expect heavy falls in U.P. (west) and good rains in Delhi Thursday thru Friday. Some heavier falls in Utterakhand. Heavy rainfall in central Nepal and Kathmandu region Thursday night/Friday.
W.D. (JU-2) is tracking east, and will precipitate rains in Kashmir and H.P. on Thursday/Friday. Expecting mild snowfall in the higher reaches.

A persisting UAC over Gujarat may swing the off shore trough from "off" to "on" again. In fact, I would think the trough may activate and spring up an off shore vortex in the south Konkan region by Friday.
Heavy rainfall expected in South Konkan and Mumbai from Friday thru Saturday. Can anticipate up to 10-12 cms in certain places along south Konkan Friday/Saturday.
Interior Mah will be without any meaningfull rain next few days. Except light rain showers in Vid. Expecting rainfall in North interior Karnatak Friday.

Pune: Thursday: Cloudy with drizzle in some areas.

Friday; Cloudy, with a shower in some parts in the evening. Rain amount 5 mms. Saturday: Cloudy with a shower or two in parts. Saturday rain amount 5-10 mms.

Mumbai: Tuesday and Wednesday weather was on expected lines. 3/4 showers, some heavy in certain areas. We had intervals of sunshine in the afternoon. The average rainfall between Colaba and S'Cruz recorded was 25 mms on Tuesday and 32 mms on Wednesday. Vagaries estimation was up to 25 mms on each day.

Thursday: 2/3 heavy showers in some parts during the day, interrupted by bright intervals. Tendency for rainfall to increase by night. Rain amount during day around 15-20 mms and another 30 mms at night. (All rain amounts mentioned are average rain between Colaba and S'Cruz).

Friday: Frequent showers with overcast day. Showers will be heavy and with gusty winds. Increase itowards evening /night . Rain amount around 70 mms.

Saturday: Frequent showers with gusty winds. Some showers accompanied by thunder. Rain decreasing after night. Rain amount around 55 mms.

Tuesday, July 26, 2011

Tuesday evening the monsoon trough axis was south of normal position, and the UAC over south Gujarat running into the Arabian Sea is now south of Saurashtra coast. Setting the conditions for re-activating the off shore trough along the west coast.

Yesterday's UAC mentioned in vagaries also persists off the A.P. coast. I see the UAC persisting ( as a UAC) for a few days more in the same region.
International MJO forecast models Forecasters have pushed the MJO in our region getting weak (date) to 3rd August. On checking various models, i summerised the weak phase to now commence from around 3rd/5th August. Previously, in the begining of June, vagaries had estimated, based on other models, the weak phase to beginaround 25th July.

As the west coast trough remains partially active, average (normal) showers along the Mah.and Karnataka coast on Wednesday/Thursday, with light/moderate rains in Gujarat for Wednesday.
N.Interior Karnataka may see some enhanced rainfall after Friday, assuming the off shore trough activates by then.Some heavy falls can move into the N.Karnataka region from Friday, as there is a possibility of an inland vortex forming.
Some rainfall to continue Wednesday/Thursday, 27th/28th, in South interior Karnataka, and in coastal T.N./ Southern A.P. due to UAC.
Rainfall sure to increase from Wednesday thru Friday in U.P. and Delhi.

I see the precipitation moving away from the Sindh coast, from Wednesday, as the original system has weakened and moved west. Cloudy weather for Karachi next 2/3 days, with minimum precipitation.

Seeing the situation as very fluid, i will not attempt to forecast beyond 2/3 days. I beleive Forecasts changes should be minimum to avoid confusion.

See Mumbai Page for those interested in Mumbai weather (updated on Tuesday night).

Monsoon Axis "Falls of the Hook" !!

Yesterday’s Monsoon trough line on Vagaries Map is the Normal Position for this time.

Just observed it has slid South.

If it remains in this position for next 24 hrs: Then with embedded UACs in it, it can bring very good rainfall to Gujarat, North interior Mah. And Vid and North A.P.

It can re-activate the west coast off shore trough (meaning enhanced rains for Mumbai), and it also indicates the MJO will remain active for another week beyond 26th July.

Please let us not jump to any conclusion , as the axis can move back North in next 12 hrs.Wait and watch.

Monday, July 25, 2011

Please note, yesterday's weather formation possibilities put up are "long Term" that is the possible weekly change. I have stressed upon the "Coming Week" terminology, meaning the 2 mentioned probibilities are the changes probable DURING the week, not overnite. MJOs change from active to supress gradually, and the change indicators are mentioned in the first option (1).
On the first day of our analysis, point (a) and (c) of option {2}. seems to be prevailing.


On Monday, heavy rains have been reported from almost all the regions of Saurashtra and some places in central/south Konkan.
W.D. has brought precipitation to Jammu region and H.P. Also Northern Pakistan faced the W.D. with 129 mms in Islamabad on Monday. System moving East.

Reason best explained thru the vagaries map below.

Comparing yesterday's map, the 850 UAC has moved south-west, and the 700 UAC also south-westwards.Yes, these can move SW, as the upper air trough runs along about the 21N line.

Rainfall has pushed into the Sindh coast on Monday. On the basis of the vagaries map put up, i think south Pakistan coastline can receive rains on Tuesday as well.
Karachi may get rains upto Wednesday it seems.

Moisture from the UAC will continue to precipitate rains in Saurashtra, and since there is almost an overlap to 2 turbulences, the region could get thunder showers.
Bharuch could be cloudy, with a few showers on Tuesday.

Expect precipitation in Vid. on Tuesday/Wednesday.
Nagpur can expect cloudy weather with few showers on these days.

South Mumbai received a couple of sudden downpours in the late afternoon. Showers were not widespread but in some parts of Mumbai. Colaba measured 74 mms till 8.30 pm while S,Cruz recorded 5 mms.

Tuesday: Partly cloudy, with a few heavy showers in some areas. Sunny intervals will make it reach 31c in the day. Rain amount 20-25 mms.

Wednesday: Partly cloudy with sunny spells. 3/4 showers, a few heavy downpours in parts of the city. Rain amount 20-25 mms.

Pune: Tuesday/Wednesday: Parlty cloudy with sunny spells. Light drizzles in some parts. Max temperatures around 30c.

Sunday, July 24, 2011

First, the actual situation:
BB4 as an UAC hangs around the Gujarat/Sindh border as an UAC at 700 mb. Another UAC lingers over south Rajasthan at 850 mb.
The monsoon axis line is shown in the vagaries map.

Now, for next week, there are a 2 distinct possibilities of weather formations:

1. In the event of the MJO getting supressed (this coming week):

a) The west coast trough gets weaker, and reduced rainfall along the west coast and south Gujarat. Both the existing UACs vanish.
b*) The monsoon axis shifts northwards (gradually), and reaches the Himalayan foothills. Reduced rainfall along west coast, NW India, Central India and Northern and interior Peninsula. Also dry into southern regions of Pakistan.
But, Increase in rains over the Himalayan states, Northern U.P., and Gangetic belt and NE states.
Subsequently, increased precipitation in Nepal, and Kathmandu can overshoot the month's normal figure. More precipitation for Northern regions of Pakistan, upper Punjab and adjoining areas, and Northern regions.

(b*) developments would would gradually occur in 3/4 days during this week.

2. In case of MJO showing no weakness and remains active (at least till this coming week):

a) Monsoon axis remains along current line, with normal precipitation along its length. West coast trough can fluctuate from weak to strong. Southern Sindh coast showers may linger along coast for a couple of days into the week.
Western Nepal continues to get rainfall.
b) An UAC can form in the bay and move inland towards the end of the week (27th/28th). Possibilities of precipitation in Delhi, Haryana and NW India.
c) Another weaker UAC, seen forming in the in the southern Bay, can strengthen and bring some precipitation into T.N.

Next 2/3 days developments will be the indicators.

Saturday, July 23, 2011

Mumbai By-Passed ! In fact N.Konkan region totally by-passed. BB4 weakens fast, real fast. And moves away very fast. Precipitation as per late Saturday night has already moved into extreme west Gujarat's Kutch region and across the border.
Anyway, i had mentioned not to expect much from this system. Light rainfall will now move into lower Sindh and Karachi on Sunday. Would not be surprised if it fades away fast, looking into the last 24 hrs behaviour.

For Mumbai, Sunday will be mainly hot with sunny intervals. Residual moisture might just bring a few showers into Mumbai on Sunday.Showers could occur around satellite towns of Mumbai on Saturday night.
But, rainfall in decrease mood from Sunday into next week.

Pune will be warmish on Sunday. Partly cloudy with drizzles in some parts. Decrease from Monday

The west coast off shore trough is now weak. OLR map indicates (light blue) this weakening off the Konkan region.
Chances of strengthening would have been there as long as the system was present.

Is the supressed MJO phase setting in ? Will the axis move north and create break monsoon conditions ? what's in store next week ? Shall discuss the possibilities of next week's weather, for N. India, Central and S.India in tomorrow's (Sunday) blog. Chances increase for Nepal rainfall.
Will be put up by 5 pm.

Ok, now Imd announces BB4 has weakened since morning and an associated upper air cyclonic circulation extends upto mid­-tropospheric levels. Fair enough !

But, the associated precipitating clouding has moved westwards even faster. Morning we noticed thick clouding over Western M.P. and approaching Eastern regions of Gujarat. Presently, at 4 pm, we see the mass of clouds having slid into the Saurashtra peninsula, and having thinned out in eastern Gujarat. Current intensity of rain has decreased since the morning observations.(BB4 going weaker).
For Bharuch, light rain showers remainder of today, reducing by night.

Infact, at this rate, I see much of Gujarat rainfall decreasing by Sunday evening. And, the rainfall, though weak, creeping into Sindh coast a day earlier. By Sunday evening Karachi should get its anticipated (light) showers.

Signs of West coast off shore trough getting weak ! MJO effect ??
BB4 tracks westwards, and has maintained its low status at 996 mb. Currently over M.P. and extends vertical as a UAC up to 700 hpa height. Tracking west, precipitation expected on Saturday over West M.P, Eastern Gujarat, and to a lesser extent over Saurashtra and North Konkan. Shall put up position again at 4 pm.

Check Vagaries’ International Page for U.S. Heat Wave, and For an in depth Detail of U.S. Heat Wave..catch up on Mark's Blog...

Friday, July 22, 2011

According to IMD latest reports, the low, BB4, is now a depression over SE Uttar Pradesh.
Maybe, though I do not read the situation as such. BB4 is moving west on same strength. Varanasi witnessed (depression centre as per IMD) peak winds gusts of 27 knts (avg 20 knts), and Easterly. And calm conditions (peak at 11 knts) in Allahbad (very nearby). Ambikapur, with SW winds at 3 knts. Pressure has not gone below 992 mb at either place today. These are the cities around the "depression" as per IMD.

I feel BB4 does not justify the up-gradation. It is left to the readers to take their call.

Anyway, BB4 is moving west, and has precipitated good rainfall in Vidarbha and East M.P. Jabalpur recorded 94 mms today, Ambikapur 56, and Gondia (Vidarbha) saw 61 mms.

Moving west, it will bring rains to remaining parts of M.P, North interior Mah, and Konkan by Saturday, and move the precipitation into the Gujarat region.
I feel rainfall will be concentrated in the Saurashtra peninsula and South Gujarat region. Baroda and Bharuch regions will get some heavy showers on Saturday.

In spite of the IMD up-gradation, i feel, as stated yesterday, one should not expect too much fom this system, and precipitation will be moderate, not too heavy. And short lived, maybe till Monday.

BB4 clouding shows bright chances of moving into the Sindh coast from Monday. With moisture laden winds, and level of convectivity favourable, precipitation along southern coastal Sindh is possible. Karachi will get light showers on Monday and Tuesday.


Saturday/Sunday: Cloudy to overcast conditions, with 4/5 heavy showers. Possibility of heavy showers on Saturday night. An increase in rains compared to Thursday/Friday. Rainfall lessening from Sunday night onwards. Rain amount 50 mms accumulated for Sat/Sun.

Monday: Rainfall decreasing.


Saturday/Sunday: Overcast to Cloudy. Light/medium showers in some areas. Rain amount 5-10 mms. Rainfall decreasing from Monday.

Earlier Post>
IMD says system ,lets number it, BB4, becomes a depression and is now at SE Utter Pradesh, 75 kms from Varanasi.
Few questions !! Varanasi pressure at 5.30 was 993 mb, Allahbad pressure was 992 mb and 1 mm of rain. Ambikapur , again nearest, pressure 993 mb, with only a drizzle. Gaya, nearby, pressure was 994 mb and traces of rain.
Original BB4 pressure as a low was 994 ! And, there is no clouding near the centre, in the nearby peripheri in central U.P. Seeing clouding around Mah.
More later tonite.

Thursday, July 21, 2011

click HERE for larger map

Low, (not giving it a nomenclature), formed on land over West Bengal, is extending up to 850 hpa level over the same area.

Expect it to move west and fizzle out over M.P.around 23rd. Rainfall along its track is shown in the weekend Vagaries map.

A slight increase in rainfall along the Konkan and Karnataka coast could be expected at the weekend. It must be remembered, that its a temporary boost, and rainfall can decrease after Monday.

Since this low has an associated upper air circulation, there are even chances of an upper air circulation from this low continuing and moving west after Sunday into Gujarat and later into the Sindh coast, albeit as a very weak circulation. Needs to be observed on day to day basis.


Thursday was almost dry with a few shaowers. Rainfall measured in the day was 5 mms, with sunny intervals.

Friday will be partly cloudy, with a few showers. Rainfall on the increase from night. Rain amount 15 mms.

Saturday/Sunday: Cloudy to overcast conditions, with 3/4 heavy showers. Some parts could get a few prolonged showers. Nominal increase in rains compared to Thursday/Friday. Rainfall lessening from Sunday night onwards. Rain amount

30-35 mms.


(Tentative estimate): Rainfall decreasing.



Partly cloudy to sunny, with light drizzle in some areas.

Saturday/Sunday: Cloudy, with sunny intervals. Light drizzles in some areas. Rain amount 5 mms.

The All india top 6 this SWM till 21st July 2011. All information from Pradeep's blog (highly recommended reading).
1. Kollur – 4452
2. Agumbe – 3638
3. Gaganbawada – 3558
4. Sangameshwar – 3337
5. Cherrapunji – 3048
6. Kadra – 3029

The 10000 club:Major inputs from Pradeep's blog again.
1.Cherrapunji (Meghalaya)
1974 - 22763
1961 - 10933 mm (This includes an mind boggling 3046 mm rainfall in 11 days starting from July 1st to July 12. During July, 1961 Kottigehra got 5370 mm rainfall in one month)
1959 - 12026 mm (During July, 1959 Hulikal got 5026 mm rainfall in one month)
1961 - 12720 mm (During July, 1961 Hulikal got 4234 mm rainfall in one month)
1961 - 10527 mm (During July, 1961 Agumbe got 3592 mm rainfall in one month)
1921 - 10294 mm (Starting from July 22 to August 21, Matheran got 5693 mm in one month. This includes 485.9 mm on July 23 and followed by 657.4 mm on July 24)
6. Mahableshwar (Maharashtra)
1896 - 10221
1976 - 10316 mm (During July, 1976 Shirali got 4206 mm rainfall in one month)
1978 -11381 mm (During June 1978 Shirali got 4439 mm rainfall in one month)
1980 - 11180 mm (During June 1980 Shirali got 3779 mm rainfall in one month)
1981 - 11477 mm (During June 1981 Shirali got 4121 mm rainfall in one month)
1921 - 10004 mm (During July, 1921 Buxaduari got 3267 mm rainfall in one month)

Latest on weather tonite at 10.30 pm

Tuesday, July 19, 2011

It would be worth recalling that an active MJO period was forecasted on this blog from 5th July. About 2 systems from the Bay were expected and a re invigorated monsoon all over India during the period was forecasted.

BB2 moved in from the Bay on the 5th of July and brought good rains in central India and extended the rains into the North. BB3 followed, though not as strong, and precipitated over central India and later again into North India.

An UAC from a Bay system tracked across M.P. and towards Gujarat bringing rain a plenty into M.P.and Gujarat. All along, the west coast benefited with the off shore trough getting a continuos lift.
Last week, an UAC had moved across interior Mah. and attracted inflow of moisture clouds on the Konkan coast.Again, copious rains in interior Mah, and the UAC lingerd over Gujarat for 2 days. An "urgent" vortex formed over the North Konkan coast on the morning of 17th.

Today, Monday, we see the UAC lingering over Gujarat, having extended its stay by a day. The monsoon axis is at its normal position.

But, the rains seems to have given interior Karnataka and T.N. a partial miss. Not much benefit and precipitation advantage for these states last 15 days.

But, i would re-read the blog published on 30th June again. The MJO was slated to remain active till around the 25th of July. It seems, as per calculations and observations today, it is heading towards an in-active period. A supressed MJO seems to be on the cards from around 25th July.

A supressed MJO, in the sub-continent region, would mean less than normal ,and supressed monsoon activity. One of the possibilities could be transalted in the monsoon trough pushing far Northwards into the Himalayas.

Vagaries will keep readers informed on this.

Mumbai Page updated with latest on city weather.

Sunday, July 17, 2011

24 cms at Koyna, 19 cms at Tala, 18 at Murud, 13 at Ratnagiri, 11cms at Mumbai Colaba and S'Cruz. These are some of the heavy rainfall figures from the Konkan region as on Sunday morning. These may not be exceptionally high, but worth the mention as the development towards this sudden rainfall is worth a study and mention.

To start with, Vagaries had put up a note just last night (Saturday 16th) of the possibilities of the west coast off shore trough re-organising and strengthening from next week, i.e. earliest could have been Monday 18th.

Late (Saturday) sees the pressure fall at the 700 hpa, over the South Gujarat coast, and form a UAC. Coincidently, the sea level pressure along the North Konkan coast started falling, and reached a nadir of 997 mb at 5.30 a.m.(also mentioned by a reader).

At the tropospheric level, a vortex ran down from the South Gujarat vortex, to form another "thin" vortex along the Konkan coast. (Seen on the map). This development "occured" at approximately 2.30 a.m. Sunday, as the winds changed from South to North in Mumbai.

The natural result of all this was quick clouds forming along the off shore trough around the vortice.

The Gujarat UAC is expected to survive, and the temporary "thin "vortex along the Northern Konkan coast was too weak to stay put. Hence, i estimated, in the morning flash, the heaviest of the rains for Mumbai from this to occur before afternoon time, Sunday.

Predictions can be made and calculated as per the synoptic situations, but quick, fast and contrary developments and changes are very difficult to estimate. Most of the forecasters fumbled on this as far as the timing was concerned. Many a times, different models calculations and estimates differ.

Outlook: UAC will precipitate rains over the North Gujarat ,Saurashtra peninsula and adjoining Kutch on Monday, and move west. If the system persists over the region, maybe for a day , the rains will naturally linger on over Gujarat for an extended time.

It could be a possibility now, that this system could bring some rains to the Sindh coast from Monday/Tuesday. Expecting, and hoping, Karachi to receive its monsoon rains from this system early next week.

Meanwhile, the precipitation along the monsoon axis (with UAC embedded) would be heavy over the M.P. region. North M.P. can receive heavier rainfall of up to 100 mms on Monday. Region around Sagar in M.P. seems to be vulnerable.

The Konkan region precipitation will return back to "normal".

Mumbai Colaba received 111 mms and S'Cruz 106 mms till 8.30 am Sunday, most of it after 3 am Sunday. Panvel measured 70 mms up to 8.30 am Sunday.

During the day on Sunday, Colaba measured 22 mms and S'Cruz 24 mms.

For Monday, i would estimate a normal monsoon day. Cloudy with 4/5 showers and strong gusts during the showers. Bright intervals between showers. Rain amount 30-35 mms.

Viewing and seeing the present situation, would estimate a reduction in rains intensity (with sunny intervals) Tuesday and Wednesday.

Rainfall total at Colaba: 1114 mms. and S'Cruz 1455 mms. Last year, 2010, on date 16th July it was 1389 mms and 1383 mms resp.

Pune: Due to moisture incursion, i estimate some showers in Pune in parts on Monday and early Tuesday. A showers in some areas could be moderately heavy. Raiin amount 10-15 mms.

Reduction in rains from Wednesday.

After a dry Saturday, heavy rains lashed Mumbai commencing pre dawn.It was observed that the winds suddenly changed from a Southerly direction after 3.0 a.m. Sunday, to Northerly. Indicates a abrupt development of a "thin" line of low pressure vortex off the Konkan coast from South Gujarat to South Konkan coast.
Between 3 am and 8.00am Sunday, Colaba measured 50 mms of rain, while it was 23 mms earlier from Saturday 8.30 am till 3.00 am Sunday. Correspondingly, the figures were 90 mms and 12 mms for S,Cruz. A wet Sunday morning indeed for Mumbai.
Satellite townships of Navi Mumbai and Panvel can get very heavy downpours in the pre noon hours of Sunday.

Saturday, July 16, 2011

"Ma-On" could devastate Japan...Rare Snow in China....All on Mark's Blog...
See also International Page...

BB3 now weakening over M.P. Chances of UAC vortex over Konkan next week bright as off shore trough re-organises.

Seeing no prospects of rain over Sindh (and Karachi) soon.
Rainfall Toppers from 01.06.2011 to 15.07.2011 (45 days).
Rainfall in mm's (Min 1750 mm)

1. Kollur (Karnataka) - 3605
2. Gaganbawada (Maharashtra) - 2732
3. Cherrapunji (Meghalaya) - 2715
4. Agumbe (Karnataka) - 2548
5. Sangameshwar (Maharashtra) - 2532
6. Quepem (Goa) - 2510
7. Kadra (Karnataka) - 2445
8. Valpoi (Goa) - 2112
9. Siddapura (Karnataka) - 2076
10. Gerosoppa (Karnataka) - 2051
11. Gorkhana (Karnataka) - 1981
12. Karkala (Karnataka) - 1941
13. Bhagamandala (Karnataka) - 1926
14. Kanakavali (Maharashtra) - 1882
15. Piravom (Kerala) - 1882
16. Canacona (Goa) - 1870
17. Chinnakallar (Tamil Nadu) - 1864
18. Rajapur (Maharashtra) - 1847
19. Ratnagiri (Maharashtra) - 1844
20. Vadakara (Kerala) - 1838
21. Bhira (Maharashtra) - 1838
22. Mahabaleshwar (Maharashtra) - 1829
23. Bhatkal (Karnataka) - 1808
24. Lanja (Maharashtra) - 1800
25. Sawantwadi (Maharashtra) - 1790
26. Sanguem (Goa) - 1780
27. Buxaduar (West Bengal) - 1726

Taken from Pradeep's Blog. His blog has always fascinated me, with his on-the-spot details and rain amounts. Recommended reading and can be found here.

Friday, July 15, 2011

See Mumbai Page for weekend forecast and latest review of July

BB3 , stubbornly weak, is positioned over M.P. And it is today enveloped by clouds. Embedded in the monsoon trough now, and due to its sudden pulling of the clouds, fairly good rainfall can now be expected over north M.P, Delhi, H.P. and Utteranchal. A weak W.D. will interact with BB3 on Saturday and bring heavy rains in H.P.and Utteranchal.
Warning of flash flooding and landslides in the mountains of Utteranchal.

Good rainfall reports received from Nepal today. Kathmandu with 23 mms was pleasant at 30c.Highest rainfall was in Birendranagar with 85 mms. The above system brings rain into the region.
BB3 not expected to go westward into Pakistan.

Cloudy with moderate showers over all regions of Gujarat (except Kutch) on the weekend. Rains between 10-30 mms.

Rainfall has reduced in interior Mah and Karnataka. As per the attached "precipitable Water" map from NuWe, there could be future cause of concern for south interior Karnataka and interior T.N and Kerala.

Thursday, July 14, 2011

BB3, as seen in the Thai map, has moved inland, and as on Thursday evening was a weak low over south Chattisgarh and adjoining Vidharbh. IMD report also confirms this.

Yesterday we had forecasted good precipitation in interior Mah. and N.Gujarat. Well, these regions were blessed.
In N.Gujarat, Dangs reported 27 cms and Kaprada 21 cms amongst the heavy weights. Vortex over Marathwada (see blog) is weakening.
Marathwada region had heavy rain, with Udgir recording 16 cms and Jalkot 13 cms.till Tursday morning.
In Konkan belt, highest was at Ulhasnagar recording 19 cms and Thane 18cms. and several places between 14-16 cms. The rainiest spots in Konkan.
Vagaries had estimated a few places with 15 cms. Panvel measured 13 cms. All till Thursday morning.

On Thursday, rainfall moved into E.Rajasthan and North M.P. regions.

The Monsoon axis at sea level runs thru Rajasthan, M.P. and then southwards into the low pressure (BB3).
The upper level troposphere axis runs thru North Arabian sea thru Mah. and North A.P. This is keeping the SWM active over the region

Upto Thursday morning, Mumbai measured up 93 mms and 57 mms at S'Cruz and Colaba, averaging 75 mms for the city. (Exact estimation by Vagaries).

Mumbai had heavy showers pre noon, with a decrease in intensity after around 1 pm. Till the evening, the city measured 44.mms and S'Cruz 84mms. The other AWS stations mesured between 35 mms (Worli) and 65 mms during the day. (Vagaries estimate 35-40 mms).

Lakes got copious rainfall, with Tansa notching up 20 cms.

Thursday Night will be wet with heavy showers. But, showers are expected to "slow down" after around 2 am (Friday morning). Satellite townships expected to witness real heavy downpours around mid night, reducing gradually by morning.

Friday will be cloudy, with bright intervals. Much less rainfall as compared to Thursday, with a few 3/4, heavy showers of much lesser duration. Rain amount average 30 mms.
Saturday/Sunday: Parly cloudy with sunny intervals. Some heavy passing showers, giving an impression of a rainy day, but stopping abruptly. Rain amounts 20 mms per day.

Interior Mah. will be drier from Friday, as the Vortex fizzles out. A distinct decrease in rains in Marathwada from Friday, but BB3 will precipitate some thunder showers in Vidharbha on Friday, only to decrease from Saturday. BB3 is showing clouding in the western and SW segments.

Pune will be partly cloudy on Friday. Week end will be cloudy with sunny intervals. Light drizzles and very light showers in parts of Pune.

For Nagpur, a showers or two on Friday. Clearing after Friday evening. Cloudy on the week end with drizzles in some parts.

This week's UAC over Gujarat was expected to shift westwards, and benefit the Sindh coast of Pakistan. But the system got stuck over the Gujarat region for 2/3 days, and got embedded in the upper level monsoon axis.

Expected to push some clouding into Karachi on the weekend. Except for some traces of rain in some areas, no rains expected till Monday in Karachi.
Hyderabad (Sindh) will be dry and temperatures in the 40s during the weekend.

Wednesday, July 13, 2011

The low in the Bay, BB3, has been acknowledged by IMD today, and is now off the North A.P./Orissa coast. At present, today, it is devoid of any clouding, but should attract clouds within 24 hrs. It could be in the west or southern segment.

The UAC over Gujarat mentioned yesterday persists over the Gujarat and adjoining M.P. region. We had expected this UAC to move west by Wednesday, but seems to have taken a voluntary delayed decision to stay put !
The vortex over Mah. has resulted in good precipitation in interior Mah and parts of Vid. Good precipitation is expected next 12 hrs in interior Mah. and eastern Vid, and in North Gujarat regions.

Konkan will get heavy rains on Thursday with heavy falls up to 150 mms.
Interior Karnataka and T.N. will be almost dry with very scattered rainfall.

As the Monsoon trough had moved North, Fairly good rainfall has commenced again in Eastern Nepal. Expect the rain to reduce for some time from Thursday evening thru Sunday.

Mumbai : A few prolonged heavy showers on Wednesday night.

Thursday will be cloudy with 3/4 fairly heavy showers of prolonged durations up to 30 minutes and high winds. Post late afternoon, the rain frequency will decrease. Rain amount average 35-40 mms.

Friday: Showers frequency decreases as compared to Thursday, and bright sunny intervals during day. Rain amount average 20 mms.

Pune: Light rains on Wednesday night. Thursday will be cloudy with a few showers in parts of Pune. Drizzling on and off. Clearing by evening.Rain amount 10 mms.

Friday: cloudy with a few drizzles in parts. Less precipitation compared to Thursday. Rain amount up to 5 mms.

1. A weak low has formed in the Northern Bay off the Orissa/W.Bengal coast.

2. Resultantly, the Eastern end of the monsoon axis has dipped southwards. The monsoon trough has an embedded UAC, NE of Mumbai

3. Our third expectation, the west coast off shore trough. This has now strengthened,(map above) and has an embedded UAC, at 700 hpa. The map also shows a vortex formed over Marathwada and adjoining Madhya Mah.

Expecting heavy precipitation, due to the vortex, on Wed/Thurs over Maratwada, and Madhya Mah. And,Vid. will have moderate rains. Rains decreasing from Thursday evening in interior Mah. and Vid.

Nagpur will get some rain on Wednesday evening thru Thursday, maybe around 20-25 mms. accumulated Wed thru Thurs.

West coast will be lashed by heavy rains.
Heavy fall in Konkan, with some readings going upto 150 mms by Thursday morning. Interior Karnataka not expected to get the brunt.

Mumbai: Wednesday will be wet with regular showers, most of them heavy. Heaviest showers in South mumbai possible around 1pm-2 pm. A decrease in rain intensity and frequency around afternoon. Resuming heavy showers by evening. Rain amount upto Thursday morning averaging 75 mms, could measure up to 100 mms in some parts.

Thursday: Lesser frequency rains from afternoon onwards. Overall rain amount decreasing, with few showers in evening. Rain amount 50 mms.

Latest report tonite by 10.30 pm

Tuesday, July 12, 2011

2 awaited parameters for SWM gaining start materializing : 1. Low forms in Bay off Orissa/W.Bengal coast. 2. Monsoon axis eastern end slopes down southwards towards low.
Watch now on 3). Off shore trough. (Posted @ 1 p.m. Tuesday).

Widespread clouding is seen in the Dahanu to Alibag belt. A rain patch covering the Dahanu region was expected (see last night's Blog), but it has stretched southwards to Alibag.
Showers expected to decrease post-noon, though Navi Mumbai and Panvel can get some heavy falls late morning. Matheran expected to be lashed by heavy rains today.

Monday, July 11, 2011

The Monsoon trough line is "oscillating", as the IMD puts.Yes, it is hovering N/S of its normal position. The axis line, today, is North of its normal position, and is near the break monsoon position.

In fact, the upper tropospheric trough has also shifted North, and is almost aligned with the sea level trough (See Thia Map). As this (upper) line moved away North, the prospects of the Northern end of the west coast off shore trough strengthening diminished on Monday.

And alongwith the axis line, our forecasts also oscillate ! The fortunes of the off shore trough now hangs on the behaviour of the monsoon trough. Infact, on Monday,11th, the Northern end of the off shore trough vanished, and a ridge is seen in place! Another 24/36 hrs, before this ridge reforms back into a weak trough.
Since a low (BB3) is expected to form in the Bay by 12th or 13th, I expect the monsoon trough to slide down as soon as this (BB3) is formed.

Renewed rainfall for Mumbai once BB3 emerges, sea level trough moves down, and off shore trough reforms along the N.Konkan coast (in that order -:).

As mentioned earlier, the upper air trough was expected to move its moisture into the Sindh coast from Monday. But, as the "parent" body has moved North, Karachi's wait for rains is prolonged by a couple of days. An UAC (at 700 mb) has formed over Gujarat. It is precipitating heavy rains over the state on Monday.
N.Gujarat, Sabarkantha dist: Bhilda 180 mms, meghraj 170 mms and Wakaner 166 mms. More rains are expected along the Baroda/Ahmedabad region. Heavy rains could be the scene in Dahanu regions of N.Mah.

This, as a expected to move west in the Arabian Sea, West of Okha,Gujarat around Wednesday, 13th. Hopefully, Karachi and the Sindh coast can get some precipitation from this, though by then, it will not be heavy.

The ENSO-neutral conditions are present across the equatorial Pacific. Since some atmospheric circulation anomalies still reflect aspects of La Niña, international models estimate a possibility of a return of the La-Nina by September 2011. But, only 33% of the various models estimate a return of the La-Nina event.
Too early to judge impact on SWM .
In fact, I feel, SWM will be out of it, and the NEM impact could be studied at a later date.

Not seeing a rosy picture today (Monday) for the predicted strengthening of the off-shore trough (west coast). Possibilities of this west coast trough gaining strength was seen earlier. But,due to the total fizzling out of the upper air trough, off shore trough will remain weak on Monday.
Hence, the Mumbai (and satellite towns) forecast for Monday stands changed to sunny with few showers. Rain amounts 10 mms. Next forecast tonite.

The scenario in the Bay remains hopeful for a low by tomorrow.

Saturday, July 09, 2011

Good inflow of moisture into the UAC over Rajasthan has precipitated copious rains over Rajasthan (Highest 202 mms in Ranivada) and Gujarat Friday thru Saturday. In Gujarat, Halol with 195 mms and Vijapur with 132 mms were amongst the highest. Even the desert region of Kutch has received rainfall on Friday and Saturday.

M.P. stations like Guna and Gwalior measured 73 mms and 60 mms respectively.

A weak trough along North Gujarat, at 700 hpa (tropospheric level) is seen weakening from Sunday. As the trough fades, decrease in rainfall from Sunday is seen over Gujarat and Rajasthan.
Similarly, interior Mah. also dries out from Sunday for a couple of days.

The off shore trough along the west coast, strong as of now due to the "booster" on Gujarat, also shows some weakening on sunday. But, can possibly re-organise itself from Monday.
Konkan will see some decrease on Sunday in precipitation. On the possibility of the west coast trough reorganising, a revival to some extent is possible from Monday itself.

However, a weak circulation over U.P. is seen precipitating rains over U.P. and North M.P. and pushing into Nepal on Sunday and Monday.

Now with the SWM current entrenched in Kutch, I see some moisture , and light rains pushing into the Pakistan coast, up to Karachi. Light rainfall, up to 5-10 mms, along the South Pakistan coast could be inplace from Monday thru Thursday.

Mumbai: With the Friday estimate thrown out (with 150 mms), Saturday was more like it (for vagaries). On Saturday, precipitation was 14 mms and 23 mms at Colaba and S'Cruz. (Estimate 20-25 mms).

Sunday, 10th,: Cloudy with 4/5 periods of showers. Some will be heavy (possibly post-noon) in different parts of the city. Inter-sparsed with bright intervals at times. Rain 25-30 mms.

Monday, 11th: Cloudy, with some heavy downpours. Increase in rain frequency, possible as off shore trough strengthens. Windy during rains. Rain 30-40 mms.

Tuesday, 12th: Overcast and frequent showers. Rain amount 35-40 mms.

Satellite townships like Navi Mumbai and Panvel could see some increase in rain frequency on Monday, with around 40 mms rains.

Friday, July 08, 2011

The UAC, stubborn remnant of BB2 has moved northwards to East Rajasthan.
Also heavy rains in Pakistan Punjab as expected. Heaviest being Lahore 104, Sialkot 98, Bannu 67, Sargodha 39. Highest in Pakistan, 46c at Dadu.

In the 12 hrs from 8.30 am to 8.30 pm Friday: Mumbai Colaba 33 mms, S'Cruz 101 mms. (Vagaries, estimate for Friday was 25 mms)

Think we revert back to original Vagaries' Fri/sat/sun forecast (Put up yesterday) now onwards?

Reports say Panvel got 3 cms yesterday.

A Weather Event, as Rare as a "Blue Moon":

The Atacama Desert Experiences Heavy Snowfall...for those interested on International Page.

sridhar: I think, its my view, that we could get uniform widespread rain if it comes from a system, i mean direct impact. There the entire region would get rain almost uniformly, like if a depression comes into Mumbai..still of course there could be little variation,not so much though.Or, if there is uniform flow of winds across the coast towards a strong system.
This is a belt of rain, un- uniformly formed, and we can call it "out of turn", so distribution will be vastly uneven.

And distance between north and south Mumbai is 40 kms, enough to create variations in precipitation.
If we review the rainfall last night: Palghar 209 mms, Colaba 163 mms, Uran 154 mms, Surat 132 mms and Santa cruz 117 mms. Thats for N.Konkan.

Another low could form in the Bay, this time off the Orissa/W,Bengal coast by the 12th.We will have to watch and wait to know its track and intensity.

Absolutely correct svt, no model had forecasted rainfall in excess of 50 mms. vagaries had put up max. of 35 mms, and reconfirmed the same yesterday. A sudden gush of moisture, towards the UAC, in a belt stretching from Mumbai in the South to Vapi in the North was the reason of the heavy fall.

But, these are the Vagaries of the Weather !
During the monsoon, narrowing of sea level isobars, and very narrow streams at the upper level of 850 hpa, could cause a sudden rush of moist winds towards a system. The off shore trough gets activated.

(Nuwe weather map)

As soon as the isobars distence widens, there is a sudden lull in the gush ( decreasing winds).

Most of the models had predicted the low (BB2) to move from the Bay into M.P. and then fizzle out in Rajasthan. Some models predicted the low to become an UAC and move into Gujarat, while a single model had estimated the low to move NW.
Another had estimated the low to become an UAC on crossing land.
While some had predicted no low at all !

On these basis, various international models calculated the rainfall path from the east thru M.P. Some estimated up to 50 mms of rain in North Konkan, and some as less as 20 mms. All on the basis of the system taking the normal path, and winds rushing into the system, in the N.Konkan region.

Vagaries' estimate was based, as explained often, on the calculation that the system would fizzle, become an UAC, and fade away in Gujarat. Hence precipitate 35 mms on Thursday in Mumbai. All this happened, with 80-170 mms in Mumbai !

Though most parts of Mumbai received very heavy rains thru last night, surprisingly, as per the AWS stations put up, places like Nana Chowk and Worli received as little as 35 mms. compared to 168 mms as the highest at Colaba.

Thursday, July 07, 2011

BB2 as a system has almost faded and exists as an UAC in the western region of M.P.
A decrease in rainfall from Friday in N.Mah. and Saurashtra areas of Gujarat. The Vadodra, Surat and Bharuch districts of Gujarat can receive heavy rainfall on Friday.

The above map shows Vagaries' estimate of Fri/Sat/Sun accumulated rainfall. The monsoon trough is in its normal position, so rainfall is expected along the line. Off shore west coast trough will bring rain along the west coast, around 40-50 mms in next 3 days.

The easterlies blowing north of the axis are likely to bring in moisture and nominal rains in the region shown, including Nepal.
These winds can blow some rain into Northern Pakistan areas.
Sindh region is expected to be dry and hot, with the hottest possibly reaching 45c.

Mumbai: Wednesday/Thursday was wet and frequent showers pushed up the total by about 40 mms in the last 36 hrs.

Friday will see some showers, heavy in the day. But the rain is not expected to be prolonged, and a decrease in the evening and night. Rain amount 20-25 mms.

Saturday: Cloudy, with 3/4 showers at times in different areas. Rain 20-25 mms

Sunday: Cloudy, with sunny intervals. A few passing showers, will be heavy, in certain areas. Rain 20 mms.

Pune: Will be cloudy on Friday with sprinkling of rain . Saturday can see a few showers, some quite heavy in areas. Sunday will be cloudy to partly sunny.

From Mark's Blog.Massive Arizona duststorm Video. Worth Sharing.

  21st  July afternoon post Comparative rain till 21st morning: Panji 2525 mms ( 100 ") and Ratnagiri 2572 mms ( 102") cross 100&q...