Thursday, June 30, 2011

Some related links sent by Neeraj from Nepal. Links: 1 2 3

Wednesday, June 29, 2011


Check Mumbai Page for June update of City

A low has formed inland near South U.P. /North M.P. border. This is the result of an embedded UAC in the trough axis descending to sea level.
I do not read much in this, and expect this low to merge in the axis. Subsequently, it is expected that the axis would move a bit North from Thursday.Thus a reduced rainfall in regions south of the trough axis.(See note on Monday's blog).


As the wind chart shows, the formation of the low has reduced the direct " easterly wind flow into H.P. and Northern Pakistan. As a result, rainfall will be generally reduced in H.P, Punjab and Upper regions of Pakistan from tomorrow. The highest amounts in H.P. was at Nahan which recorded 210 mms, Dharamsala which measured 83 mms till today morning. Nainital in Utterakhand measured 70 mms.
In Pakistan, Lahore recorded 98 mms of rain on Wednesday.

The weak MJO phase prevailing in the North Indian Ocean regions, (that is in our 2 seas on either side of the sub-continent), is expected to gradually see a reinvigoration from 5th/6th of July. This would enable the SWM to gain momentum, and we could very well see BB2, form after around the 5th of July.


As the existing trough line moves north, the first week of July will bring normal rains into Northern U.P. and Utterakhand.
As one would expect the active MJO to last around 20 days, we can presume at least 2 systems from the bay after 5th of July till 25th of July. Presuming a normal course inland, we can expect some excess rains along the central states and Gujarat, and normal rains in the southern peninsula.

Mumbai:

Thursday: Cloudy, with a few passing showers. Rainfall decreasing from evening, and



Friday/Sat/Sun will be sunny, with partly cloudy skies. Few showers in some areas. Hot day temperatures on Friday/Saturday.





Northern Pakistan Rain Likely:

Strong moisture laden easterlies are prevailing North of the monsoon trough. Originating from the Bay, they are pushing thru North M.P. and adjoining U.P. into H.P. and finally into thru Northern Punjab into the Northern regions of Pakistan. In Northern Pakistan, these winds are interacting with J2.
Northern cities in Pakistan, including Islamabad have received heavy rainfall. Islamabad measured 59 mms while adjoining rawalpindi got 68 mms. Several cities in pakistan Punjab got between 30-70 mms.
More details can be found on PWP with rainfall amounts in Pakistan.


This inflow can continue for another day, as the axis remains stationary till Thursday. On this line moving North, rainfall could abate. Another day could cause flooding if rainfall exceeds 75 mms in places.

Tuesday, June 28, 2011

Vagaries had mentioned the trough line remaining steady today(Tuesday), with rainfall along the line, and east Rajasthan getting more rains Tuesday.

The monsoon trough is steady along the same lines as yesterday.The rainfall continues along the trough axis, running thru Rajasthan/M.P. and Jharkhand. Guna(M.P.) received 122 mms and Kota(Raj) 103 mms during the day on Tuesday.
The trough may shift North from Thursday, and the resul in decrease in rains in regions mentioned in Monday's blog.

Mumbai Thunderstorm assessment on Mumbai Page.


Rainfall just around Mumbai !! Cloud width is less. I mean if one sees west, there is not much backing to this cloud. But height caught on is 12 kms.

Thundercell around Mumbai region ! Vagaries taken unawares.

A strong thundercell over Mumbai pulled up a surprise storm, with loud thunder and heavy rain.
Doppler shows the entire region around Mumbai being lashed, upto Thane in the North, and Alibag down South.
Intense clouding upto 12 kms high produced the thunder. West is more cloudy, and pushing into Mumbai !
Doppler and report at 4 pm.

Monday, June 27, 2011



Monday's position of Monsoon Trough (Purple Line) indicates a very slight shift Southwards. As discussed yesterday, rainfall is centred along the axis line today.


As J2 is gone, Vagaries estimates a steady position for the trough till Wednesday, before it shifts Northwards. Till Wednesday, rainfall continues along the trough axis. Rainfall will be concentrated to the east of Rajasthan. Gujarat expected to remain almost dry.
Special Gujarat report on 1st July.

On its shifting North, a decrease in rainfall could be possible from Central India down to the South.

Status Quo of Sunday/Monday weather for Mumbai to continue Tuesday/Wednesday. Expecting a further decrease in rainfall from Thursday.

Light rains in Pune next 2 days, and almost dry from Thursday.


Sunday, June 26, 2011

J2, a weak W.D. has moved into the upper regions of the sub-continent. As it is weak, precipitation is moderate in H.P, Kashmir, extreme north Pakistan. Will move away NE within a day.
But, its inter-action with the monsoon axis and the embedded UAC (ex-BB1) has produced heavy rains in Punjab, Haryana and Delhi regions in the last 24 hrs.


SWM moves into Punjab and North Rajasthan.



We have to wait and observe whether the combined effects of J2 and ex-BB1 moves the axis northwards into position (1). If it does move further north, position (1), active rains along the axis and Nepal, but subdued rains south of the line. Position(1) is a "pucca" break monsoon scene.

If the axis remains in the same position, rainfall can continue along the axis line.

But, axis in positon(2) is not a break monsoon scene, and Central India/West coast and Northern peninsula can continue to get rains, though a bit subdued due to no systems present. Also, in this case, SWM can move further west into west Rajasthan.

Saturday, June 25, 2011



Hi, after a Mahableshwar "break",


The current weather Map/Charts of the sub-continent reflects a typical monsoon chart, with the monsoon trough running from Rajasthan thru U.P. and Jharkhand into the Bay, and an eastward extension of the trough running into the NE states.
This is much better than having a " break monsoon" situation , where we see the trough running in a further north position along the Himalayas. And, this could very well have been the scene today with a weak MJO situation in force. With BB1 having embedded itself in the trough, the trough line has remained a bit to the southward position.

Expecting the weak MJO phase to remain till July 1 st week. In vagaries, we had discussed this phase and anticipated its arrival after the fizzling away of BB1.
But, in the current scenario, rainfall will be persistent along the axis, that is east Rajasthan, northern M.P, adjoining U.P. and Jharkhand. Good rainfall in the NE states.

I observe the off shore trough to be more prominent south of Goa. Showers could be expected along coastal Karnataka, and to a lesser extent in south Konkan and Goa.

What's in store for the next few days, the rest of June ?

It may well happen, that with the BB1 remnants "raining out", the monsoon trough, or axis, could start moving to the north, and settle down into the Himalayan foothills. Then, the whole rainfall scene shifts north, more northwards than the areas mentioned above. This could well be the scene with no momentum and push from either of the seas. In such a situation, substantial increase in rainfall in Nepal and adjoining U.P. plains, and Utterakhand hills.

Movement of monsoon rains westwards into Sindh (Pakistan) almost ruled out in this period,

Till the supressed MJO persists, it may not be possible for any of the seas on either side to bring up a system. The current SOI is +3, after maintaining an average of +18 in the last 5 months.
BB2 is just a dream now, and could be a not reality before 4thJuly, at least. That is presuming the MJO phase to "give in" after that date.

A ray of hope would be to expect a pulse, to move west from the current depression "Haima", now over North Vietnam. It could sail into the bay, and if it does, it could be as soon as by the 29th.

Mumbai will to have this miserable hot humid weather thru the weekend. a short duration shower to two may give on the spot releif, only to get more stuffy once the sun is out. Meaningfull rains increament not in next 4 days at least.

For those interested, Pics and videos of Mahableshwar trip on inter-actions page.



Dangerous heat over Spain and Portugal, London and Paris eyeing hottest days in over 2 years...read more on Mark's Blog.


Thursday, June 23, 2011


BB1 almost over and out. Just a low now. Will merge with the trough running thru Rajasthan, North M.P. and Chattisgarh.

Wednesday, June 22, 2011




I am in Mahableshwar now. Its been overcast, foggy and very frequent heavy showers throughout the day today (Wednesday). Gusty winds during showers bring wind chill temperature down to 15c. Max day temperature today here was 18c, with 65 mms of rain from 8.30 am till 6.30 pm. Fog visibility down to 3 metres at times. Minimum last night was 17c.
Cumulative rainfall from June 910 mms.

Tuesday, June 21, 2011


BB1 now positioned at the M.P./U.P. border, about 150 kms W/NW of Rewa. At a pressure of 996 mb, the system is maintained its designation. Movement is slow and steady.
Though not precipitating unusually heavy rains in its path.

Its movement in the next 24 hrs, presumably W/Nw, will precipitate rains in west M.P. and lesser amounts in in adjoining Rajasthan , and eastern Gujarat.

I anticipate a SW flow of moisture towards the system, as it moves west, from the N.Konkan coast.
The location and positioning of BB1 would be such, that with the off shore trough organising along the konkan coast, the SW winds would be activated towards BB1.

Precipitation would increase along N.Konkan and in the ghat regions from Tuesday night or Wednesday.
Mumbai could have more frequent showers on Wednesday, with overcast conditions and strong SW winds. Rainfall would amount to around 40 mms .

The writer is currently in Mahableshwar (since Monday), and frequency and posting of detailed blog, becomes difficult. Will be back in Mumbai on Thursday, and most probably with a posting on Thursday night. Queries would be answered then.

Monday, June 20, 2011


BB1 has taken the middle path between option 1 and option 2.And currently at 25N and 82.5E,at about 996 mb pressure. Remember, it began as 996 mb pressure. A well marked low.
The trough from the system runs SE into the bay. Could get organised in 2/3 days this trough.

Sunday, June 19, 2011




The Depression BB1 is now currently situated at 23.4N and 84.5E, near Ranchi, Jharkhand. Showing a westerly movement in the last 6 hrs, and NW before that. After having poured torrential rains in Bengal and Jharkhand, Jamshedpur and Ranchi both measuring 161 mms, and Darjeeling 101 mms, it is weakening and will continue on its track. Records around the centre (on Sunday) show rainfall of around 50-60 mms in the last 9 hrs.
SE quadrant of the system shows thick bands pf clouds, over Chattisgarh and parts of Vidharbh.

The SWM has now covered Bihar and Jharkhand and Eastern Nepal regions. BB1 movement will push the SWM further into east U.P/M.P.


BB1 is slowly and surely getting weaker, and as mentioned, I do not expect it to survive, as an effective system, beyond 2 more days. Once the system weakens, the "bloated " clouding will precipitate some rains into central India (M.P.).

Rainfall pattern will alter in the Indian region.
Heavy precipitation will continue in the Northern M.P./U.P. belt, along with good rainfall in Nepal. A worrying factor is the deficiency in the NE states.

Begining Wednesday, We could see some decrease in rainfall in the Central, Western and Southern regions. Infact, I think the Southern Peninsula may be almost dry and warm. Like wise, I see almost dry conditions in NW India, interior Mah, and Gujarat region. The projected weak MJO will take charge.

NW India, Delhi Gujarat and West M.P. will be deprived of SWM advance this coming week.
With a weakish off shore trough, and no systems or UACs in the next week, rainfall will continue to be weak along west coast.
Mumbai will be hot and humid..very humid. Passing showers might not provide any relief.

Its been a very hot Sunday in the sub-continent. The hottest place was Turbat (Pakistan), at 49c. Incidently, the place had avery low humidity level of 6%.
And the hottest in India seems to be Bikaner and Hissar, at 42c. In the absence of a W.D., west Rajasthan and Sindh (Pakistan) will continue to remain hot, maybe get hotter and reach 50c in the next 2 days.


Friday, June 17, 2011


BB1 lies as a deep depression at 22.4N and 88.5E, 50 kms NW of Kolkata. On crossing over Kolkata, the city had 107 mms of rain at Alipore and 117 mms of rain at the airport, in 9hrs on Friday. Currently on the mentioned location, the pressure is at 990 mb.

As mentioned yesterday, there are 2 possibilities for the system to track.


-1. BB1could track North/North-West, thru Northern parts of Bengal and into the Northern trough. By Saturday evening, it would weaken a bit, and move into Central and Eastern parts of Nepal. Fizzle out by Monday over the Nepal Himalayas. Result: Heavy rains on Sat in Bengal, Bihar, Jharkhand and Central/Eastern Nepal. Also good rainfall in Eastern U.P.
In this case, rainfall along the west coast would weaken from Monday, and a "break monsoon" situation" of reduced rainfall in Mah, Gujarat, Karnataka and west M.P. would prevail.

-2. BB1 would track West/NW, and move along into Chattisgarh by Saturday/ Sunday. Later moving west, it would track into M.P. and fizzle out there by Mon/Tues.
Here, heavy rain in Bengal and Bihar and Jharkhand on Sat, and then in M.P. and Vidharbha on Sun. On Sunday, rainfall could increase along the west coast as the system moves westinto M.P. System would fizzle out by Tuesday over west M.P.

Vagaries would go in for scenario No. 1.The first option seems more probable.

Mumbai:
Saturday/Sunday: Uncomfortable humid heat. Sunny intervals with some showers, but not prolonged. Passing showers will be sharp. Rain amounts about 25 mms per day.

Thursday, June 16, 2011



BB1 has moved North! Much against expectations and deepened into a deep depression, at 984 mb, and crossed the West Bengal coast. According to the NRL site, it lies centred at 22.1N and 88.8E. Exact location seems at the India/Bangladesh border, on the Gangetic delta.

SYSTEM WILL CROSS OVER KOLKATTA TONITE. Very heavy rains expected.

Its northward track has prevented the mass inflow of rain clouds onto the Konkan coast on Thursday. Some infow from the west was expected if the system would have crossed land near the Orissa/Bengal coast.
But due to a Northwards diversion, we see good winds and clouds flow towards the west coast all along upto south Mah.150 kms south of Mumbai as on Thursday 10 pm.

Mumbai's expectation of rain showers on Thursday was thwarted. In an average expected normal situation, on the system crossing the coast at 22N, a westerly rush towards the system should bring rains to Mumbai on Friday.

1.-Now that the full scene has shifted a bit North, I think a North/NW track would carry this system along into Bihar, Jharkhand and U.P. FInally, after a couple of days station itself in the Northern trough. Resultantly, SWM could push into Nepal and U.P. This, I fear, might create a "break Monsoon" condition for the central/Western and Southern regions. Maybe from as early as Monday 20th/Tuesday 21st.(Does that ring a bell ?? Like we discussed in yesterday's Vagaries ? Weak MJO ?)

OR,
2.- BB1 could move West/NW, and track along the Chattisgarh-North M.P. route. This, on the other hand, this could enhance rainfall in the central regions of India,west coast and push SWM into M.P. and Chattisgarh.

In either situation , remember, the clouding and rain is in the SOUTHERN QUADRANT of the system.

Lunar Eclipse Images from Around the World; June 15, 2011..here

Wednesday, June 15, 2011


The Thai Met Office Chart shows the low, well marked now at 996mb.
As explained, BB1 is expected to move along the trough already prevailing in the North.The (imaginary) line joining the 3 lows in the Northern region of the Sub-Continent is the trough position.
But, it should be remembered, that though BB1 will move tracking the trough, initilly north till hitting land , and them NW. The cloudings of this system are in the Southern half, hence, precipitation will travel with the system's Southern quadrant. since system is not deep, will fizzle out by reaching North M.P.

After nearly a year with La Niña conditions, both oceanic and atmospheric indices have dropped to neutral conditions across the Pacific Ocean.The 30-day (SOI) on 11 June was +7.7.

If one recalls, Vagaries had mentioned in its long term forecast for June of a weak MJO phase after 25th June. Well, it (unfortunately) seems to be on schedule.
International forecasters feel, MJO will be in a weak phase from roughly 20th June. But, they caution this time the waxing-waning is a bit "erratic". Rainfall in central/peninsula and NW India can become erratic, in such phases.
I feel erratic may mean normal to below normal, not the other extreme such as very high precipitation.
Shall keep posting on this .

Live eclipse here: http://www.livestream.com/swansiliguri (Thanks Akshay).

Tuesday, June 14, 2011


IMD has announced the formation of a low (Our BB1) in the Bay off Orissa/W.Bengal coast. As per NRL, it centre is located at 20.5N and 90.4E. With a initial core pressure of 1000 mb, BB1 its precipitation intensity is likely to intensify in the west and SW of the low.
System itself will deepen a notch or two in the next 24-36 hrs.

The system, i expect, will get embedded in the trough, now running along the Northern plains from Pakistan thru Punjab thru U.P.
Initially, heavy rainfall is expected in Orissa and W.Bengal on Wed/Thurs.
Later, Thurs/Fri, rainfall will be heavy in East Vidharbh, eastern M.P. and Jharkhand.
The eastern end of the trough with the low, getting stronger, SWM will move into eastern Nepal and W.Bengal, Orissa next 2 days.

I do not foresee BB1 going any further than eastern U.P. before merging with the trough.

West coast trough is getting back into "shape" fast, and has organised itself, ready for heavy rainfall along coastal Karnataka and Konkan from Thursday.
Vagaries map shows rainfall estimate for wed/thu/fri.

Mumbai:Tuesday rainfall was 33 mms at Colaba and 24 mms at S'Cruz.


Wednesday: Cloudy skies with passing showers of slightly longer duration than previous days. Rain amount 25-30 mms. Doubt if Lunar eclipse will be seen.

Thursday: Overcast with frequent and short spaced rains towards evening. Rain amount 35-40 mms.

Friday: Overcast. Oft- and -on heavy showers (not continuous) in regular intervals. afternoon showers accompanied with thunder.Rain amount 45-55 mms.

(Rain amounts are mentioned as it helps judge the quantum of rain which can be expected. Suggested by a reader-says it helps in "knowing" how much rain to expect, specially when compared with 2 consecutive days).


BB1, is likely to descend to seal level as a low pressure by tonite. Initially, at around 998 mb, it will form off the Orissa coast, with clouds in the southern and SW quadrant of the system.
Since a seasonal trough today runs from west to east, with its western end over Upper Sindh and running thru Rajasthan, U.P. and the eastern end into the system.

Normally, BB1 will track along this trough. Presuming the trough to remain in the same position, which it should, the low, on deepening into a well marked low by Thursday, will track into North M.P. and thence into U.P.

But, bearing in mind the clouding is in the south and SW of the centre of BB1, rainfall will be more in Eastern Vidharbha initially, and moving into east M.P. from Thursday/Friday. Similarly, the eastern end pf the trough will get active to precipitate heavy rains in the NE states, and presumably move SWM into more areas of the east and Nepal.
In line with BB1, west winds will be attracted towards the low on the west coast. Heavy rain along North Konkan accordingly from Thursday. Mumbai forecast put up yesterday remains intact !

As-1 is now out and over, done with. Precipitation is dying out off the Saurashtra coast. I understand there were traces of rain in Karachi yesterday. Dont think more can be expected from "ex-AS1"

Next update with forecast map tonite at 10.30 pm.

All India Toppers SWM Rainfall from June 1 to 12 - 2011. Compiled and sent by Pradeep. Thanks.
Rainfall in cm's (Min 50 cm)

Vadakara (Kerala) - 82
Piravom (Kerala) - 80
Kollur (Karnataka) - 78
Kottigehara (Karnataka) - 73
Devala (Tamil Nadu) - 71
Gaganbawada (Maharashtra) - 70
Sangameshwar (Maharashtra) - 68
Karipur AP (Kerala) - 69
Vaikom (Kerala) - 64
Agumbe (Karnataka) - 61
Bhagamandala (Karnataka) - 60
Gerosoppa (Karnataka) - 59
Kannur (Kerala) - 59
Ammathy (Karnataka) - 58
Sholayar (Tamilnadu) - 57
Vythri (Kerala) - 57
Cherrapunji (Meghalaya) - 57
Karkala (Karnataka) - 55
Honavar (Karnataka) - 55
Peermade (Kerala) - 54
Gorkhana (Karnataka) - 54
Ratnagiri (Maharashtra) - 53
Quilandy (Kerala) - 51
Kozhikode (Kerala) - 51
Chinnakallar (Tamilnadu) - 49
Shirali (Karnataka) - 49
Mumbai Santa Cruz (Maharashtra) - 48
Mangalore AP (Karnataka) - 48

Monday, June 13, 2011

The well marked low, AS-1, has moved further NW, and remains inland, just on the Saurastra coast, but weakened. Rainfall belt has shifted to west Gujarat (Jamnagar) and adjoining Kutch.
Clouding however has spread over a greater radius.
As the system weakens, in the next 12 hrs, the clouding (not heavy rain but high clouds) will "swell" into a wider region for a day.

I feel BB1 will come to sea level off the Orissa coast by Wednesday, straught away as a 998 mb low.or maybe a well marked low. SWM progress into newer regions will depend on the track of BB1.Most likely track west.Meanwhile, it may take 2 days for the off shore trough to re-organise itself. Details later tonite.

Mumbai Forecast:

Monday: Partly sunny/cloudy with few heavy short duration showers. Rain amount about 15-20 mms.

Tuesday: Intervals of sunshine with a couple of showers in the day. Evening could see a heavy shower. Rain amount about 20 mms. Real feel will be hot due to humidity on Mon/Tues.

Wednesday: Cloudy skies with passing showers of slightly longer durations than previous days. Rain amount 25-30 mms.

Thursday*: cloudy with frequent and short spaced rains towards evening. Rain amount 35-40 mms.

*tentative. Could be revised.

Sunday, June 12, 2011



International models also show the centre of AS-1 on land, between Junagadh and Veraval in Gujarat.

Very heavy rainfall in Saurashtra as on Sunday morning in cms: Sutrapada (dist Junagarh) 27, Veraval (dist Junagarh) 17, Kodinar (dist Junagarh) 9, Talala (dist Junagarh) 8, Upleta (dist Rajkot) 8, Manavadar (dist Junagarh) 6, Dhoraji (dist Rajkot) 5, Junagadh (dist Junagarh) 3,


AS-1 has weakened considerably in the last 6 hrs. Sat image as on 10.30 IST Sunday. Pressure rises to 1004 mb, and winds at 25 knts. Just about a well maked low now. And having moved NW

Precipitation quantum has now reduced, with heavy rains restricted along the SW coast of Gujarat.

Mentioned yesterday about the J1 effect. That's it. AS-1 will weaken in the next 6 hrs, and move NW.
Clouding along eastern region of Sindh coast on Monday, with light to medium rainfall. Clouds will reach Karachi, by Monday/Tuesday, but rainfall ? Yes, a question mark. Maybe just around 5 mms. (Really, hope I go wrong for the citizens )!

J1 is precipitating rainfall in the northern regions of the sub-continent.
Good rainfall like 106 mms in Dharamshala, 38 mms in Mandi and 30 mms in Bhuntar (all H.P.) and 18 mms in Jammu and 12 mms in Simla was recorded. Various places in Kashmir received between 10-20 mms. Some rain was measured in Punjab too.
Across the border, J1 was active, and precipitated 52 mms in Gujranwala, 44 mms in Muree and 40 mms in Islamabad besides 10-20 mms in other cities in the North.



The above developments will keep the SWM stuck in the western sector in the current position , 20N along west coast, and inland as seen in vagaries map. Northern/Central India and Gujarat will have
to wait longer.

SWM could have moved into Gujarat, but the rainfall from AS1 was in the SW corner of Saurashtra,and South Gujarat and eastern parts were bereft of precipitation. See rain map.

But, BB1 is poised to intensify, and good graduate to a low soon. On happening, will move the SWM into Nepal and more regions of Bengal.




IMD has announced the depression has crossed the Gujarat coast at 8.30 am Sunday near Diu,which is 20.4N and 70.6E.

Location of AS-1, as a depression, shown on the graphical map as on 11.30 am IST from JTWC.
The latest location as on 2.30 pm IST (Sunday ) is 20.8N and 70.3E. Winds are steady at 30 knts.
Exact centre location in such systems are always a matter of conjecture and made on calculations with MSLP measurements.

Moving very little to the NW, almost quasi -stationary in the last 3 hrs , the system's maximum life intensity seems to be on peak. Expected to weaken ,as anticipated, within the next 6 hrs.

Predicted movememt is NW, and I feel the direction will hold. But, the speed of tracking is slow, and if the current speed is maintained, then the weakening and precipitation effect will be in a restricted region , mostly in coastal and southern Saurashtra.

Clouding is now in the NW-West-SW quadrant of the system. AS-1 clouding should move into the eastern coastal regions of Sindh by Monday. Clouding with limited precipitation could be expected in lower coastal Sindh regions on Monday.
Next update 3pm IST

Saturday, June 11, 2011

AS-1 intensified a bit in the last 6 hrs, and pressure now at 996 mb. At 20N and 71.7E, it means it has moved NW since last observation.
Moving towards Saurastra coast and subsequently the Sindh coast. As anticipated, will skirt the coasts. Weakening trends possible from Sunday night.

J1, a fresh W.D. is advancing into Northern India via N.Pakistan. Surely will have some effect on the SWM and track of AS-1.

Day temperatures have seen a slight downward trend, with Dadu (Pakistan) being the highest in the sub-continent at 47c. The highest in India on Saturday was at Kota at 44.3c and Bikaner 43.8c.

BB1, the bay low, persisits in the Northern Bay as an UAC, and has pushed the SWM into Bangladesh and Sikkim today.
Next stop Kolkata and Nepal.

Mumbai:

In the 12 hrs ended 8.30 pm on Saturday, Mumbai Colaba received 102 mms and S'Cruz 181 mms.

A few showers of short duration on Saturday night.

Sunday: Cloudy, with short sunny intervals. Short duration showers.

Foot Note:

Vagaries had a query in the comments column a few days back. "Why does vagaries SWM advance dates differ from IMD"? I had explained my reasons and what parameters I refer to when doing this. In fact I repeated that i follow the norms as per IMD.

Mumbai SWM was advanced by IMD on 5th June. Vagaries advanced SWM into Mumbai on 9th June. Quoting below from the "Times of India", Dated 11th June, , page 2, (Mumbai edition) what weather officials at Colaba clarified:

Quote-"So despite the torrential downpour of June 2-3, Met officials insisted any rain before June 10 was a pre-monsoon shower. It was only on June 5 that an embarrassed bureau decided to announce that the monsoon had arrived. "Thundershowers usually indicate pre-monsoon activity but we had to make the announcement, or else people would say the rains were evidently here and we were ignorant," Sharma said". -Unquote

AS-1 note has been put up at 8pm today.

Stationary at present, but likely to move NW and intesify initially. Moving towards Saurastra coast and subsequently the Sindh coast. As anticipated, will skirt the coasts. Weakening trends possible from Sunday night.

Mumbai:

In the 12 hrs ended 8.30 pm on Saturday, Mumbai Colaba received 102 mms and S'Cruz 181 mms.

A few showers of short duration on Saturday night.

Sunday: Cloudy, with short sunny intervals. Short duration showers.

The coastal belt of Goa and Mah. received very heavy rainfall due to spiral binding of clouds from As-1.

Rainfall in 24 hrs ended 8.30 am Saturday:

Very heavy rainfall of 21 cms was recorded at Mahad and Mahbleshwar and Poladpur had 17 cms.Harnai 14 cms while Bhira and Roha had 11 cms while Mumbai Colaba guaged up 10 cms. Panvel received 8 cms.

In the Ghats section, Tamini had 14 cms and Koyna 10 cms.

With the system pushing in moisture and rain Northwards, I feel that a further advance of the SWM into North Mah. and South Gujarat is getting favourable.

Next update at 11.30 pm IST Saturday.


In last 2 images which were put up in the last blog publications, including the 1 pm and the image of 6.30 pm IST just put up, there is no "eye" indication. The "dent" that I have mentioned in the last write up at 1 pm was also to just indicate the centre of the system since many were puzzled as to the locations regularly given.

Plus, an eye needs a solid swirl around it, and a swirl needs a core pressure of at least 988/990 mb. So a system with a core pressure, actually its not even a core pressure, the pressure "around" the centre is hardly 1000 mb as per latest observations, fit enough to designate it as a depression at the most. Again, last recorded winds are at 28-33 knts only, not befitting a cyclone.

But, JTWC and NPMOC have made it TC 01 A. Not named it though.

AS-1 at 19.7N and 71.9 E and seems quasi stationary. SE quadrant clouding has reduced in the last 6 hrs. Will intensify initially now onwards, before weakening again.

Another report and rainfall details at 10 pm.


Current position of AS-1 system is 19.5N and 71.9E, as on 12.30 pm IST. Sat image of 12.30 pm IST ,Saturday. The centre is in the "dent" in the cloudings.

Clouding spiral band now covering SE quadrant also, Compare with 6 hrs ago. The reason Mumbai and North Konkan getting heavy rain.
As the trend shows a NW track, Rain intensity in Mumbai and Konkan should diminish (not stop) by late afternoon, not before that.
(This, checking on the AS-1 system seems to be going on for ever ! -:)))

The clouding shows the entire Southern periphery of the system to be enveloped alongwith SE now. With a central core, in the clouded periphery showing very heavy rains.

Proper Mumbai should get heavy rains thru the afternoon. See some decrease late afternoon early evening. Flooding sure in prone regions during afternoon. outer townships, may get some extended period of rains.



Current position of AS-1 system is 19.5N and 71.5E, as on 4.0 am IST. Sat image of 9.30 am IST, could be read, and a judgement made of the current centre as 20N and 71.5E. Thats my calculation.
(This, checking on the AS-1 system seems to be going on for ever ! -:)))

The clouding shows the entire Southern periphery of the system to be enveloped. With a central core, in the clouded periphery showing very heavy rains.
As per the radar, (and as it is very very difficult to predict the movement, and the cloud movement of AS1), the entire Mumbai region, was covered by rain clouds in the morning. Subsequently, after 9.00 am, the rains advanced into the outer townships like Thane and Panvel.

Proper Mumbai should get heavy rains , at least till 11 am,(flood warning ) but outer townships, may get some extended period of rains (also warned of flooding).

Mumbai received 103 mms of rain at Colaba, most of it post Friday evening.


"Heavns have opened up the flood gates and pouring by buckets here in Mahabaleshwar". -Shiraz from Mahableshwar

.

sat. image at 8.0 am saturday

Friday, June 10, 2011


As1 sat. image at 10.30 pm ,Friday.

The next official up gradation, by international models, on AS1, will be 6 hrs after the last, i.e. at 12.30 am IST (Saturday).
But, seeing the latest sat. image, as on 10.30 pm IST, Friday, we can make a personal assessment of the movement. I think, seeing the sat. image, the centre would be at 19.8N and 71E. This is purely a calculation and observation study on sat. image.

The clouding has moved northwards into Saurashtra, and the overall NW movement seem imminent.Clouding along Mah. coast has reduced, especially in the last 2 hrs.
Next update Saturday morning 9.0 am.

As on Friday morning, Gaganbavda in Mah. received 15 cms of heavy rain, and Ratnagiri measured 14 cms (144 mms). Generally ghat stations in Mah.receive rain from systems form Arabian Sea nad the Bay. But, Bay systems and UAC are generally more effective in pouring very heavy rains in the ghats.

Mumbai lakes, are , I beleive, are having 1.92 lmls of storage water as on 5th June 2011. Last year on date was 0.56 lmls and full capacity is 13.0 lmls.

AS-1 at 7.00pm IST.
Located at 19.2N and 71.2E, meaning its movement has been NE in the last 6 hrs. The winds are at 30knts and pressure maintained at 1000 mb.
So, 6 hrs prior to our 12.30 pm report, the system had moved East, and in the next 6 hrs the track is NE.


Sat image shows most of the clouding and heavy rain now concentrated in the SW quadrant. The SE quadrant shows clouding and rains south of Mumbai, over Alibag. Been stationary in that position for the last 3 hrs now.
Was expecting a major movement northwards with the system. Mumbai had frequent heavy showers post afternoon, and South Mumbai is now getting continuous heavy rain since 7.00pm.

BB1 persists at the previous location off the Orissa coast.

Next update at 10 pm IST

AS-1 located at 12.30 pm IST on Friday at 18.6N and 70.7E. and pressure at 1000 mb.This means a slight movement due East in the last 6 hrs, and a shade weaker.
IMD still maintains it as a "well marked Low".

Now, the parameters I consider for its track show an initial NW track, at least that is what one of the components, the 200 jet streams, indicate. One should also bear in mind, that an NW direction of these jet streams at this time is not very unusual, it normally should be West.
Next Update at 1.30 pm today

Click here for full view
AS-1 agian changes course, shifts NE ! But seems will brush the Saurashtra coast.

Location 18.6N and 70 E, now about 260 kms West of Mumbai. Sat. imagery shows dense clouding to the West/South-west and SE of the centre. Pressure at 998 mb.

Thursday, June 09, 2011

As-1 Latest Status:

Currently at 19.5N and 68E, meaning having moved in a Westerly/North-Westerly track, and located SW off the Saurshtra coast. Indicators continue to estimate NW track next 12 hrs.
Sat image shows clouding in the SW quadrant and weaker clouds in the South and SE quadrants. Central pressure having fallen to 996 mb, the depression is now gradually upgrading itself towards the next notch.

Heavy rainfall and winds could commence off the Saurashtra coast by Friday night itself. It would be reasonable to expect rainfall in the range of 75-125 mms along the Gujarat coast, and 25-50 mms in the interiors of Saurashtra. South Gujarat may see rainfall in the 25-50 mms range.

Rain and winds expected in Sindh coastal regions from Saturday.

Rainfall in Mumbai and Konkan may reduce from Friday evening, as the off shore trough seems to be breaking, under "systems pressure".
Though the rainfall amounts of Konkan for Thursday are not in, nor available, we know of Ratnagiri getting 105 mms of rain till Thursday morning, that overnight, and another 75 mms in the day on Thursday. 175 mms in 24 hrs ended 5.30 pm.

Mumbai lived up to our forecast for Thursday put up yesterday, tallying to the quantum ! Colaba received 23 mms till Thursday evening and S'Cruz 38 mms. Vagaries had estimated 35 mms.

Friday will be cloudy with frequent rains during the day. Rainfall reducing by night.

The Bay system, BB1, (nomenclature changed to BB1, as suggested by our reader Ashokbhai. To avoid confusion with IMD name), has pulled up the SWM into A.P. and coastal Orissa. The NE states are geared up now to receive the SWM.
Nepal follows.


@0600 UTC 98A.INVEST is 30 knots 1000Mb. located at 18.1N 69.3E

Ashok Patel

http://www.gujaratweather.com

AS-1 Update:

Latest status and Strength as on 11.00 am IST: Depression Position 18.3N and 69.3E, winds max 33 knts in the southern periphery and pressure at 998 mb. Has remained stationary for the last 6 hrs, but deepening.

Seeing one of the the main indicators today, the 200 jet streams, it can be presumed that the depression will track the NW direction, skirting the Saurashtra and Pakistan coast. Can move due West after that towards Oman Gulf.

But seeing the SST in its onward journey, Vagaries wonders as to how much the system can really gather strength ?

True, other models still differ between themselves on the track and strength even today.

Presuming this course is adhered to, we can expect its effect along the Saurashtra coastal towns, and then along the Sindh coastal regions.

Gusty winds along Saurashtra coast could commence by Friday night.Rainfall also could commence along the Saurashtra coast from Saturday, and heavy rains barging into the Karachi regions by Monday. The sequence of time and date will be difficult to monitor and follow up at this stage.

Taking into consideration the past history of "time keeping " of AS 1, things can change. But today, the situation of jet streams and pressure parameters show this track.

Wednesday, June 08, 2011


51c again in Pakistan:

It was 51c on Wednesday in Larkana, Jacobabad and Sibbi, and 50c in Turbat (all Pakistan).

Highest in India: Bikaner at 47.6c

The exact position of AS-1:

AS-1,as a system is now deepened into a well marked low pressure, as per IMD terms. The cloud bands are getting better organised, and are distinct in the SW and West quadrant. It is to be understood, that the system has very minimal clouding in the east of its centre (read Indian coast). It is now located at 10 pm IST at 18.9N and 70.1E, which is 320 kms S/SW of Mumbai.

Now, this system was barely 55 kms from Mumbai when Vagaries reported 2 days ago. So having moved almost 265 kms AWAY from the Indian Coast, but strengthened to some extent.


The latest water vapour sat imagery shows the region above 20N as very dry, due to dry winds from the NW. The current heat wave in the Sindh, Rajasthan and Kutch regions has significantly altered the "joy ride" of this system.

With clear indications of cirrus clouds also going westwards from the system, AS-1 is now destined to travel west/north-west, (remember the zig-zag travel map put up yesterday??) and deepen a bit more.

Since I would expect it to move further away from the Indian coast, the system as a depression maybe, would skirt the Saurashtra coast and the Sindh coast of Pakistan. Precipitation would be in moderation along the Mah. or Gujarat coasts. And seeing the clouds segment in the western periphery, we could assume no meaningfull effect on Indian shores.

The same WV sat. image also indicates the stagnant SWM stuck at 18N since 5th June. Vagaries had expressed a delay in the SWM progress after 20N. And the current OLR is not favourable for SWM to move beyond 18N. (Vagaries maintians 18N, south of Mumbai, though IMD mentions the northern limit at Dahanu).

Seems a few more days waiting now, if the system is moving away.An active MJO should not make this wait long.

Meanwhile, the UAC mentioned in the Flash Snippet, is a low pressure area now, nomenclature BOB-1. It is situated off the Orissa coast at 19N. BOB-1 will initiate and push up the SWM in the eastern sector. SWM should cover A.P. and Orissa and NE states, including parts og W.Bengal.

A step towards Nepal.

Mumbai Forecast;

Thursday: Partly cloudy skies getting cloudy as day progresses. Frequent rain spells and thunder rain in afternoon/evening. rain amount reduced to 35 mms. Maybe could push up the SWM.

Konkan region will get pockets of heavy rainfall.

Friday/Saturday: Rainfall reducing.

Tuesday, June 07, 2011


Severe Heat returns to Central Pakistan and Northern India.
51.5c , that was the highetst in Asia todayand as PWP points, it is just a degree short of the record 53c recorded last year on May 26th at Mohen Jo Daro.The list of highest in Pakistan and India:
Jacobabad 51.5c, Nawabshah 51c, Larkana ,Sibbi and Sukkar 50c,
And the nights above 30c, Sibbi 32c Multan and Jacobabad 31c,

Jaisalmer 48.7-32.3c c, Bikaner 48.1c- 31.0c, Jodhpur 47.8-32.2c c, New Delhi (Palam) 45.3c.


As NT points out, AS-1 continues to puzzle and baffle forecasters, international forecasters. As is known, this system has "tracked" several differentroutes on the forecaster's models. But where is it actaully going to head, or how much is it going to intensify ? Again, international models have been toying with this system's future for the last 10 days now, and As-1 has been teasing the
"know-alls" by waxing and waning alternatively.



Presently at 18.3N and 70.9E, and with a core pressure at 1002 mb, the winds are notching up to 25 knts. The cloud segment is in the SW and South. The winds have turned to Southerlies now, indicating an intensified low in the west off Mumbai.
Models show a fresh clouding and rainfall enveloping the Mah. coast from Wednesday, their main reasoning being a fresh flow of S/SW winds , laden with moisture.

The low will intensify and move NW. As per present indicators, system will skirt along Saurashtra and the Sindh coast. Peripherial Rainfall will be heavy along the coastal regions of Gujarat from Friday and Saturday, and spreading into Sindh coast from Sunday.Maximum intensification can be off Sindh coast, at around 990 mb.

Mumbai:

Wednesday: Partly cloudy, with a few showers. Fresh South winds blowing. Rainfall amount 10 mms.

Thursday: Overnight rains. Overcast cloudy morning, with increasing in rain intensity during day. Frequent showers some with thunder and persistent. Rainfall amount 70 mms. Pockets of very heavy rains in Konkan region, and some places in Konkan can receive upto 150 mms of rain.

Friday:Overcast and frequent showers, but rain intensity and quantum less than Thursday. Rainfall amount 30 mms.