Friday, April 29, 2011

Minimum temperature touches 30c for the first time this year today, 29th April at Kota (Rajasthan). 
In 2010, 30c as minimum was recorded on 17th April.

Mumbai at 30c now at 2 pm (Friday). Almost cloudy .

via email.

Thursday, April 28, 2011

Monsoon Watch 4

Seasonal Low: Indicator: -ve

The days have started heating up in the Sub-continent since the last couple of days. 47c at Larkana in Pakistan 2 days back, and consistent 45s in the Rajasthan and Sindh regions (Pakistan) assure us of the seasonal low forming soon. But, what we still require are the severe heat waves, which are still missing.

The formation of the low is behind schedule, with the core region in the Thar desert still to form and lacks consistency. The MSLP in the Pakistan Sindh region is 1002 mb as of today. Lower since MW 3. But we must remember, that a series of W.D.s have been constantly keeping the temperatures down by as much as 5-7c below the normal.

As on end April, a pressure of 1000 mb in the central core region around Barmer is normal.

Bay Sector: Indicator: -ve

At least the high pressure mentioned in MW 3 is now dissolving, with the help of Southerly winds. Many international forecasting models indicate the formation of a low in the Bay by the 1st. of May. Pre- Monsoon low formation seen in the next week's time frame.

Previous MWs have stressed upon the importance of a low in the Bay by end April. Once a pre-monsoon low is formed, it increases the speed of the SW winds in the Bay sector. An ideal wind speed of 25-30 knts hastens the cloud formations.

Cross Equatorial winds: Indicator: -ve

Good and +ve development here since MW 3. In the western sector, the Arabian Sea branch, the winds below the equator are much better organised now, and have started curving near the equator. A Northerly gush is seen off the Somali coast. This ultimately leads to the formation of the "Somali Current" an essential formation required to accelarate the cumulus cloud formation in central Arabian sea.

Somali Currents are very strong S-N winds off the Somali coast, and this strong wind brings the SST off the coast down (by end May) to almost 18c ! With a warmer central Arabian Sea, cloud masses in huge volumes are formed in the Central area. (Shall discuss in detail in later MWs).

For now, it is sufficient to understand that the winds have turned Northwards, and have re-curved.

In the Bay sector, SW winds are organised South-West off Sri Lanka, and the SE winds from below the equator are pushing North in the Bay region. Signs of getting orgainised. SW winds just South of Sri Lanka have gained speed and are now clocking 25 ktns.

But, in the Arabian Sea and remaining sectors, the winds are still to gain speed. They could be considered weak.

With no cyclone in the Southern Hemisphere, the ITCZ could be forecasted to move Northwards. Currently it is around 5S. ITCZ movement discussed in MW 3.

200 hpa Jet Streams:Indicator:Neutral

Another parameter to observe now are the 200 hpa jet stream. Normally, they should be Easterlies right upto 20N by May end. This would facilitate the Northward movement of the Monsoon Current. Today, the jet stream is developing just below the Equator. Forecasts on models show these winds getting organised around the first week of May. Should march up to the 10N by middle of May, to be in time for the Andaman Sea Monsoon arrival.

La-Nina: Indicator: +ve

Sea surface temperatures in the equatorial Pacific Ocean have shown very little change. The weekly SST anomaly map for the week ending 24 April shows weak cool anomalies along the equator. Still, a few areas of SST anomalies of more than 1 °C cooler than normal for this time of the year now remain.

However, atmospheric indicators continue to be at odds, and remain consistent with a well developed La Niña event. The latest 30-day SOI value is +30.2. This is alomost touching the the highest April monthly value on record +31.7, recorded in 1904, and has remained consistently high throughout the event.

Cloudiness near the date-line remains below normal while trade winds continue to be stronger than normal.

Untill these indicators turn towards normal conditions, a fully neutral ENSO condition cannot be established. La-Nina prevails till then. And seems it could well slip into June.

Conclusion: Though there is some improvement in most of the parameters, there is still much to be achieved, and most parameters are still lagging behind time, and are -ve.

Based on these calculations, Vagaries would still maintain the Monsoon to reach Kerala by the 4/5th June. SWM should hit South Andaman Sea around 18th. May.

First half of June should see some deficient rains in the Peninsula regions.

MW 5 will be up on 7th May.

Many International forecasting models indicate the formation of Pre- Monsoon low pressure in the Bay by the 1st of May.
Vagaries estimates the system may ultimately develop into a depression, ( maybe upto 998 mb) at the most, and move NE towards Myanmar around 3/4 May. This direction is estimated by Vagaries seeing the SST having its "core heating" sector near the Myanmar coast.
Also a W.D. in Northern most Kashmir and Afghanistan will push NW winds into the plains of the Sub-Continent, which can divert the system towards east
Dont see much effect on Indian coastline

MW 4 being put up tonite.

Wednesday, April 27, 2011

Today’s Weather Across America: By Mark Vogan see blog for detailed U.S. Weather threat.

Another day of 'Extreme Weather' across the MississippiValley


The Heat has started gripping the Sub-Continent. The Map from the Univ. of Cologne shows the Western region of the plains now well into the 40s.

As dicussed earlier, the heat is moving into the Sub-Continent, and creeping into India now. The max temperature anomaly shows a East-West divide, temperature wise. The western region is now moving into the above normal" zone.

The Highest in Asia on Wednesday was Dadu (Pakistan) at 45c and Idar (Gujarat, India) at 44.6c.
Several stations in ssindh (Pakistan) too had 44c as their highs today. Karachi is back to 35c after soaring to 41c a couple of days back.

No meaningful rainfall, except for some convective thundershowers in Kerala and Orissa.

Some thundershowers expected in Lower Sindh region of Pakistan on Thursday/Friday. Cloudy weather for Karachi on Friday.

Though Kathmandu received 1 mm of rain on Wednesday, a little more could be expected on Thursday and Friday, tapering off by Saturday.

More discussions on the situation in MW-4, which will be up tomorrow (Thursday).

As I will be proceeding to Bandhavgarh Tiger Reserve Forest, there will be no Vagaries published till Thursday, 5th May.

Monday, April 25, 2011

This was the Monday we were discussing. The 40s are here. As expected from Monday, the days are warming up, and across the border, Larkana is touching 47c.
Map of 25th Day Temperatures (from Univ. of Cologne) shows a fair "sprinking" of 40s.

Click here for an enlarged image of Vagaries' Temperature forecast for next 4 days.

Hopefully, next MW should be positve as far as the seasonal low parameter is concerned.

Forecast For Tuesday/Wednesday/Thursday/Friday:

For Nepal however, a North-South trough promises a wettish week. Vagaries holds on to its forecast for Nepal published on the 23rd.
Tuesday thru Friday, it should rain in the eastern parts of Nepal. Kathmandu will have Thunder showers, some heavy on Wednesday, till Friday. Day will be "under control" at around 26-28c. On Wed/Thu, I feel the capital could expect upto 30-35 mms of rainfall.

For this week, Tuesday thru Friday, in the Sub-Continent, Vagaries does not forecast any meaningful rains, except thundershowers in the NE states, Northern West Bengal and Sikkim. Convectional thundershowers can pop up in coastal Orissa, Kerala and interior T.N.
Thundershowers could appear in lower Sindh region of Pakistan on Thursday.

Tuesday/Wednesday/Thursday: Partly cloudy, with high-medium alto-cumulas clouds making it stuffy and humid. Hence night temperatures will rise from the current 24/25c levels to 26/27c. Days will be around 34c.

Saturday, April 23, 2011

Monsoon Watch – 3

Bay of Bengal : Indicator: -ve

Continuing from MW-2, "Bay of Bengal" low pressure parameter is a worrying factor. Normally, the Bay should host a pre-Monsoon low anytime after 15th. April. Like I mentioned in the previous MW, last year we had a cyclone in the Bay by the third week, and in 2009 a cyclone crossed the Bay on 12th April.

As on today, this region still maintains a luke warm response to the formation of a quick low. The pressure is anything but low, and the winds indicate a weak "high" trying to establish itself. What is needed now are winds getting Easterly, to start with, and break up the existing high pressure area.

Only +ve sign of a quick formation is that the SST is conducive. Map shows around 32c near the Andaman Islands. Ideal temperature for quick low formation.

However, The region below the equator in the Bay sector continues to be favourable with SE winds tending to bend SW South of the Bay in the 95E region.

Remember, the normal date for SWM to hit the South Andaman Sea is 15th. May.

Sub-Continent Seasonal Low: Indicator: - -ve

The line of dis-continuity should shift back to its normal position, in the centre of the Southern Peninsula region.

Out breaks of pre- monsoon thundershowers are expected normally in the southern states and South Maharashtra. We are having these now. Though the showers in the South are heavier than normai, and excessive. But, a break in the pre-monsoon thundershowers is common, and will allow the days to get hotter.

An exception this year is the Vidharbha region.With exceptionally heavy rians, and more quantum wise, the temperatures are just about managing 40c, in fact just hovering around the high 30s. Normally Vidarbha is a hotbed ! 45-47c is a "kid's playground" for the region.

Nights last year were terrible at this time. See in this link, check dates April 13th and April 20th.

And contrast this with the lows today.

The sesonal low in the Thar region is also lagging behind, thanks to the absence of intense heat waves. The days, have started to rise now. Trends of rising temperatures are finally seen in Gujarat and adjoining regions of Sindh across the border. Just saw the 1st 45c on Saturday, 23rd.April. (See write up below the MW-3)

True, the entire sub-continent region has to suffer a heat wave, but the gains are much more. The pressure around the Thar desert region is now 1006mb (994mb required by June beginning). There is no central core formed as yet. And ,as per the required scheduled development, a proper gradient is behind schedule in the making.

Cross Equatorial Winds : Indicator: neutral.

The cross equatorial wind flow, has just about picked up in the Southern Hemisphere. Winds, have not yet achieved the required speeds, but just about started hitting the East African coast. Re-curving Northwards of the winds, on the Kenyan coast, is yet to occur.

That means, a high pressure region, the back-bone of our Summer Monsoon, is also slow to form down in the Southern Hemisphere, off the Madagascar Island, and in the mid South Indian ocean.

However, Cross winds in the Eastern Sector (Bay) are getting strong, and are re-curving.

Amidst this, no cyclones are likely to form off Australia this season. If no low pressure forms there till end of April, the ITCZ can start moving North. And with low pressure and ITCZ moving North, the High in the Southern Indian Ocean has a fair chance of getting stronger and anchoring well.

As the ITCZ tracks north, associated MJO waves can "ride" alongwith. Meaning, after the shift, more MJO waves in the Northern Hemosphere (read Bay regions).

The positive news from Australian Weather Bureau; " it is likely that the next MJO event to progress into the Maritime Continent region will have little influence on rainfall and tropical cyclone activity in the southern hemisphere, but more likely will begin to influence northern hemisphere weather patterns."

La-Nina: Indicator: Same as Last MW.

La-Nina is almost the same as reprted in MW 2. Not much significant warming is seen in the region.

The 30-day Southern Oscillation Index (SOI) to 16 April was +26.5.

SST in the La-Nina zone are coming to normal levels very slowly. It should neautralise within 2/3 months.

If, by any chance, there is a delay in the La-Nina coming to normalcy, it would mean more than normal rains in June, decreasing in July.

Conclusion: As of today, there seems to be a slight delay in the Arabian Sea branch of the Monsoon. And, the Bay branch needs a little trigger to get going. Maybe a little less rain in the first half of June for Kerala, Karnataka (coastal) and S.Konkan? Arrival date should be around 4/5th June for Kerala.

(This Monsoon chase is my personal view, and my personal analysis and deciphering is done as per my assumptions).

And there it is ! Our poll is over ! 46c in Larkana (Pakistan) today, 23rd April. 45c in Nawabshah and Jacobabad. Poll shows only 7% having voted for this period. Rest 93 % had opted for the 45c earlier than 21st April.

Map shows the cooler anomaly in India today, this map shows the heat slowly creeping into India.

But,as Vagaries mentioned yesterday, (see Vagaries Forecast map of 21st.) after this weekend, gone are the days of 30s for N.India, brace up for the 40s now.

The South based UAC mentioned has resulted in very heavy rains in T.N, South interior Karnataka and Kerala, for the 2nd day on Friday.
Rainfall: Yercaud 14 cms, Kanchipuram, Bangalore A.P, 11 cms, Bangalore city and Omalur 10 cms. Thiruvananthpuram measured 7 cms.

The UAC in the south is no more embedded in the North-South trough. The rains intensity in the southern states is expected to decrease from Sunday, with little rain in few pockets from Monday.

As expected, the rains in central regions of India have abated now.And keeping the hottest regions very comfortable temperature wise. Nagpur was at a high of 34c (-7c). Nights were very very low, at an average of around 20c as the minimum. See comparison being put up later tonite on MW-3.
Dry for Vidharbha and adjoining regions for next week.

On Tuesday, 26th, An East-West trough could form along the Himalayan foothills. Why I mention this is, because the Eastern end of the trough, in Nepal could get active with incursion of moisture.
Eastern Nepal could see some renewed rainfall, from Wednesday 27th. Kathmandu falls in the rainfall area. Capital can get rains on Wed/Thu next. More of this later.

MW-3 coming up late tonite by 11 pm.

Flash Update From Mark (U.K.)
@9a it's already at 17C at Heathrow Apt, a rise of 3C over the past hour.

Friday, April 22, 2011

The system in the South, an UAC, mentioned in Vagareis yesterday, is precipitating very heavy rains. Refer Vagaries Forecast Map put up yesterday.

Thunderstorms are reported from Kerala, T.N. and South interior Karnataka. Bangalore had rains today (Friday), measuring 44 mms in 9 hrs upto 5.30 pm, 68 mms in 2 days. Many centres in Kerala had heavy rains, figures of which will be known by tomorrow. Chennai is having frequent thundershowers on Friday.

As mentioned, the Nilgiris is currently receiving heavy rains, and figures have been received upto Friday. Some of the rainfall amounts in Nilgiri: Kodaikanal and Kotagiri 6cms, Combatore and Ketty 5cms.
In South Karnataka, many stations in Mysore and Hassan region got 4-6 cms of rainfall.
In Kerala, adjoining Wyanad region received 6 cms of rain. Rainfall figures for Friday will be out on Saturday, and amounts should be heavier.

As for the Vidharbha region, a direct report from "The Hitavada" a regional newspaper, speaks for itself. (Suggested by Akshay).

And the warming has commenced in the Sub-Continent.
Days have started warming up. Across the border, we see Nawabshah highest at 44c, and Karachi touches an unusual high of 41c on Friday. Now, as explained in the Vagaries Map, this heat should move east into Northern India from Sunday.

From Our Partner Blog:


UK On track for warmest April on record, temps top 80 degrees in central London

The normal is 14C in London for late April, the normal for July/August is 22C….

Scotland to enjoy a very warm Friday, but complications move in from the west on Saturday!....details in Blog.

Good Rains in Vidharbha on Thursday night/Friday morning:

Wardha gets 43 mms, Brahmapuri 36 mms and 15 mms in Nagpur as per IMD.
minimum temperature today in Amraoti is 17.8c, and 19.6c in Nagpur! 5c below normal !

Akshay from Nagpur gives the latest on Friday morning: "11mm rainfall in Nagpur with strong overnight thunderstorms."

A low has formed in the interior Mah. region as on Thursday (21st.) evening. The Thai Met map shows this. This in fact is the same UAC which had vortexed in the region yesterday. Descended now to MSL.

Click here for enlargement.

Vagaries' expected place to touch 45c, Idar (Gujarat), was 42.0c on Thursday.

Resultantly, as per Vagaries estmate, Convective activity is seen in the Vidharbha region, and adjoining South M.P. Repeat, fairly heavy thundershower in Nagpur. This area will get thundershowers on Friday and Saturday, tapering off by Sunday.

Also seen in the Map above, another Vortex in the Upper Air has formed in North Kerala, Nilgiri and South interior Karnataka.

Friday/Saturday:Expect very heavy rains in Palghat regions of Northern Kerala and adjoining T.N.( including Nilgiri) and South interior Karnataka (Hassan).

Thursday, April 21, 2011

Weather News From Nepal, Sent by Neeraj;

Rajesh ji,

Mustang is a district of Nepal located in the north of the central region.The southern part of the district is high mountains with one very deep gorge cut by a river. Beyond that, it high altitude plateau with some mountains. Hindu/Buddhist pilgrimage site of Muktinath (11500 ft asl) is located there. They say it has been snowing there even in second week of April. By that, they mean its snowing in the populated area in the lower reaches and the valleys. As snow would be normal for high altitude areas. Anything above 5000 m will get snow all year round.

District headquarter: Jomsom (9000 ft ASL)
Pilgrimage site: Muktinath (11500 ft ASL)
Northernmost major town: Lo Manthang (12500 ft ASL)

Parameter discussed in MW: Fall Out of A1, A2 and A3:

Wednesday, April 20, 2011

Vortex formed over Vidharbha and adjoining M.P. Estimated (refer blog of 19th.) heavy thundershowers can occur on Thursday/Friday. Nagpur for heavy thundershowers too, with around 25-30 mms on Friday.

via e mail.

Tuesday, April 19, 2011

W.D.s over, Heat will build up, Starting from Gujarat and moving into Northern plains from Saturday.

Northern Region:

End of the W.D. Season. Looking over the western horizon, and with no W.D. in sight, it seems with A3, we can expect the regular W.D.s to finally cease.( However W.Ds continue in the extreme Nortern regions, in N.Kashmir and above).
After the routine A3 effect, the temperatures are expected to rise from Saturday onwards. Yes, the below normal days for N.India are over after this weekend.

Sure its needed. MW has been constatntly pointing out to the seasonal low factor as "un favourable" and the making-of-the -seasonal-low events had better pick up and gain momentum now.
Delhites, forget the 30s from Saturday,23rd April, and welcome the 40s. all over the Northern plains of Punjab, Haryana, Rajasthan and U.P.hotter days could be expected, after the 25th of April, turning into heat waves.
Kashmir dry after Thursday, 21st, and warming up !

Gujarat would start heating up immiedietly. Ahmadabad and Baroda can expect to touch 44c on Thursday itself. By Thursday/Friday, I expect some hot spots, maybe Idar, to become the first city in India to touch 45c.

Maharashtra, the interiors would receive thundershowers this week. Vidharbha can expect thundershowers on 21st/22nd, Thursday/Friday, keeping the temperatures this week contained within 41c. Nagpur can expect some heavy thundershowers on Thursday/Friday, specially heavy on Friday. Similarly, convective rains could be expected in Southern regions of the state. Pune would be dry this weekend, with the days around 38/39c.

Southern states, Karnataka and Kerala, will get convective showers this week. Interior regions of Karnataka could get very heavy downpours, while T.N. interior regions would get thundershowers till Friday. Intensity of rains increasing from Saturday in Kerala.

Rainfall tapering off from W.Bengal. NW winds commencing in the NE states (and Bangladesh) will bring violent storms from the weekend.

Seeing rainfall decrease in Nepal from Wednesday itself. Remaining moisture may last for a couple of days to bring convective rains in pockets around the central region. Getting hotter from Saturday. Back into the 30s for Kathmandu.

Next MW on Saturday promises to be more +ve, if the above estimates fall in line.

Shall put up a Vagaries forecast map on Thursday to cover upto Monday.

IMD Monsoon Forecast: Normal Rains, i.e.96%-104%, with error of +- 5% , that means rains could be between 91%-109%, and that would mean a correct forecast ! What a range IMD allows itself !
If Gujarat receives 115%, and Orissa gets 85%, the overall India predictions by IMD would still be termed as accurate!
No Comments ! Forecast is like a de-flated Balloon.
No Comments !

Sunday, April 17, 2011

Weekend Weather Behaviour in Line with vagries'Forecast originally up on 15th:

Good rains reported from Kashmir and H.P.on Saturday, and specially on Sunday. Snowfall reported from some higher altitude areas of the state. Keylong, headquater of Lahaul Spiti experienced 5 cm snowfall during the last 24 hrs and high reaches of Kinnuar, Kullu and Chamba also had light spell of snow .
On Sunday, Dharamsala receives 19 mms of rain and many stations in H.P. between 10-20 mms.
Srinagar with 8 mms of rain was at a day's high of 13c.

In the plains, rains were spread all over Punjab, Haryana, North Rajasthan and Delhi, had an overcast day with light rainfall throughout. Amritsar, Ferozeepur, Gurgaon, Rohtak, Jullendar and Delhi had a thunderstorm on Sunday evening. Rain with hail storm was reported from Nainital and Dehradun. Where as rain has affected the normal life in Chamoli, Almora and Pithoragarh.
Some Highs in Punjab Cities (Vagaries'original estimate in brackets): Patiala: 32c 20c, Amritsar 32c- 17c and Ambala 31c-22c.( Vagaries'Estimated for Punjab Cities:34-18). Delhi max:37c. and min 22c (Estimated 37-22).

Pakistan: Several stations had very heavy rains between 50-80 mms.Muree had heavy rains of 66 mms, Islamabad 33 mms and Rawalpindi 27 mms. Islamabad day's high 24c,( below 25c), Karachi 36c (36c). Highest in Pakistan: Turbat at 42c.(Not more than 40c).

Now, Vagaries had predicted A3 to follow along the lines of A2 in terms of forming an induced low.
This has happened on Sunday.
IMD Sunday bulletin release states, Quote-"An induced cyclonic circulation extending upto 1.5 kms a.s.l. lies over Rajasthan and neighbourhood.The
trough/wind discontinuity at 0.9 km a.s.l. now runs from the above system to Lakshadweep area across west Madhya Pradesh, Vidarbha,
Marathwada, south Madhya Maharashtra, interior Karnataka and Kerala".

Promised Sunday review of Vortex formation over Marathwada:
An embedded UAC within this line has formed somewhere near South Mah. (a bit to the west of predicted Marathwada region), and is about to bring the anticipated rains/thundershowers into S.Mah. and spread to Marathwada ansd Vidharbha from Monday.

Also check on MW-2 put up on Saturday.

Saturday, April 16, 2011

Monsoon Watch - 2.

Further Analysis of the parameters as discussed in MW-1.

1. Seasonal Low: For this parameter, the -ve factor from the previous MW discussion is maintained, as the average day/night temperatures in the Northern Sub-Continent areas remain in near normal/below normal range.

IMD map of day temperature of the 15th April anomaly explains this.

A comparison with last year shows the difference this year. In 2010, the first 45c was touched on 10th. April, and on the same day Nagpur was 44c, Delhi 42.8c. Soon on 15 th April 2010, Nawabshah (Pakistan) soared to 47c, Simla to 28.2c on 16th, Ganganagar, Akola and Hissar to to 46c.

This year we are yet to reach 45c anywhere in the Sub-Continent.

The quick formation of the Seasonal Low due to absence of heat wave in Central and Northern regions of the Sub-Continent, continues to be un-favourable. Into the 3rd. week of April now, and the heat is missing.

As on 16th. April, the lowest pressure, in the Thar Desert region is at 1006 mb. (Last year 1002 mb this time) and this "low" area is restricted to a small area. As mentioned, it normally should reach a low nadir of 994 mb in June, and with 1008mb in the South Arabian Sea, a perfect gradiant is created to attract the south -west winds.

2. The La Niña event continues to decline in the Pacific Ocean, with a further warming of the SST in the past 2 weeks. On an average, it is warmer by about 0.2c over the last 15 days. The warming is consistent with the life cycle of past Niña events.

SOI was last measured at +26, equivalent as yet to a strongish LA-Nina event.

3. Last week, the Cross Equatorial Monsoon winds, which originate from the Southern Indian Ocean as SE winds, and cross the equator to become south -west,were weak, and not developed .

Let me explain, that the winds before crossing the equator break into 2 branches. 1) gushing into the Arabian Sea, and 2) moving into the Bay of Bengal.

Today, we find, the winds south of the equator better organised in the Bay branch, in the region south of the Andaman Sea. SW Currents are seen off the Sunmatra coast. And that is exactly where the start should be.(See extreme right of chart).

The Arabian Sea branch is still struggling to get organised. Here, a fall in wind speed off the Kenyan coast has disrupted the SE flow.Not a healthy sign,but could always re-organise fast.

The Mascrene high pressure zones in the South Indian Ocean, at 1030 mb, between Madagascar and Australia, have been observed, and the "Power House" of the Monsoon winds is slightly behind schedule,for this time of the season.

4. Another factor, which helps the winds gain strength, and bring more moisture into the Indian landmass, is the sea temperatures on both sides of the Peninsula. Optimum (warm) temperatures will hasten and create more clouds, and help in faster forming of the lows from the Bay. This parameter, is not very "normal" and tilting towards "un-favourable" as on date.

Put up the SST of last year on date. Comparison shows it was much warmer last year, i.e. above normal.

But the pre Monsoon Low in the Bay is still elusive. As discussed, we should see a low sometime after the 15th. of April. But as on today, a high pressure region prevails over the Bay.

5. To bring the existing SE winds above the equator, the ITCZ should move northwards. Around 1st. of May, this should cross the equator. The ITCZ, is in its "normal" position, as of now, at 5S. An indication is the Australian Monsoon Trough, now stationary north of Australia, around 10S, with TC embedded.

Ceasing of TC activity is a must for the ITCZ to start shifting.

So, overall, we can summarise as:

Parameter:1): -ve. 2): Normal. 3) -ve. 4) -ve. 5) Normal.

Most parameters are running -ve. as of today. In today's situation, Monsoon arrival in Kerala could be delayed by about 4/5 days , and on normal dates in the Bay Islands, and the NE states.

But, situations can change fast, and by the time we discuss the next MW, some -ve factors can suddenly become +ve. So, MW discusses and follows the developments as they emerge, and discuss the parameters as is where is.

No model can commit from today when the Monsoon can arrive. Things get clearer by first week of May. Vagaries' (in MW) normally remains true to estimates around early May.

Next MW up on 23rd. April.

Friday, April 15, 2011

A3 chugs into the Sub_Continent. Definetly no links with railway timings, W.D.s arriving bang on time.

On Friday,15th, we see A3 clouding a major portion of North and Central Pakistan, NW India and extreme North India. Rain/snow has been reported from all these regions.
Light rains measured 5-7 mms in North India and Pakistan.

Earlier, A2 had formed an induced low, in the plains of N.India, and from this low, a trough, or call it a line of wind discontinuity, ran all the way southwards into Karnataka. This trough, normally travels, or shifts eastwards , along with the movement of the parent W.D. But, in the current case, its South end is steady.
Stretching thru the central regions, this line had brought extreme thundershowers in M.P, interior Mah, Karnataka and in parts of Kerala too. In fact, it was rather heavy on Thursday in interior Karnataka, with Renebunnur (Haveri Distct) receiving 101 mms of rain.

Vagaries' forecast of thunderstorms along the trough and in Vidharbha on thu/fri/sat held good. Vidharbha too got its share.
Akshay* narrates from Nagpur on Friday evening-Quote: " a very severe thunderstorm hits nagpur with frequency of cloud to cloud lightning over 100/min.
Scanty rains but bright lightning enough to make night as morning."

It seems, A3 too, is tending to follow this trough line routine, and could result in thundershowers in central and southern interiors again, next 3 days.

The meeting of east-west winds along this line, is voilent, and results in massive build up of CB clouds, reaching great hieights, created by near perfect CAPE and
L I conditions. Ajekar, in interior Karnataka, had a hailstorm on Thursday.

The negativity of this? This will continue to keep the day temperatures down, below the normal heating range required for this time.
More of this in MW-2 , which will be put up on Saturday night.
Meanwhile, highest in India on Friday was 41.1c at Akola, and highest in Sub-Continent was 42c at Chorr (Pakistan).

Outlook for next 4 days, Sat/Sun/Mon/Tue:
Enlarge Map here.

Saturday/Sunday, 16/17th:

-A3 rains in Northern Indian states of Kashmir and H.P, with snow in higher resorts. Due to depth of system, rains/hails in Punjab,Haryana,Delhi, North Rajasthan and Western U.P. Days in New Delhi will remain around 37c, with nights dipping a bit to 22c. Cities in Punjab will be in the 34-18c day/night range.
Due to the residual moisture, interior Karnataka will continue with its sporadic thundershowers. Maybe spreading a bit north into south Mah.

-Precipitation moves into W.Nepal.

-Northern and central Pakistan will get the precipitation benefit of A3, these 2 days. Keeping Islamabad cool within 25c in the cloudy and rainy on Sat/Sun. The hottest regions of Sindh will be cloudy, and the days may not exceed 40c. Karachi, will be cloudy with the thermometer reading 36c in the days.

Monday/Tuesday, 18/19th:

-Some residual rains/snow over the hilly tracts of N.India will be prevelent.
If precipitation continues in Kashmir, then I expect snow in Srinagar on Monday.

South Mah. to get some left over pockets of thundershowers. A embedded vortex could form over Marathwada on Tuesday, and may result in thundershowers, with some drifting into west Vidharbha. This vortex point, we shall review again on Sunday.

-System moves eastwards, and slides into all of Nepal. By Monday, fairly good precipitation all over Nepal. Kathmandu to receive rains, around 10 mms Monday thru Tuesday. Days will be just within 30c. A3 fading away from Tuesday. Almost in tune with the forecast issued on 13th April for Nepal.

-With the system having moved away from Pakistan, a slight cooling at night could be expected in the North, with Islamabad reading around 13c. Karachi will maintain its clear days to around 35/36c.

Monsoon Watch-2 will be put up on Saturday night by 10 pm.

* Akshay is a regular contributor to Vagaries and a well wisher. He is a keen meteorologist which can be seen from his blog METD.

For some light Reading.. See Space News Page

An article all of us missed out in 1835…. The Great Moon Hoax of 1835


Thursday, April 14, 2011

Vagaries Wishes its readers from Nepal a Very Happy New Year !

Wednesday, April 13, 2011

Forecast for Nepal:
Moisture remains from A2 might still precipitate light rains in a few pockets on Thursday.. Subsequently, no rains Friday /Sat.

A3 starts sliding into Western Nepal areas from Sunday, and covers the country , so entire region should get rains on Monday. The stationary high anchored over Nepal at 1024, will vanish with the advent of A3, and reduce the pressure to 1020 mb. (Normally I do not give very technical and detailed explanations as they are boring for the readers. Not that I am technically qualified in Meteorology.)
Jumla should get rains from Sunday, and touch 0c on Monday.

Kathmandu, will see decreasing rains from 13th ,Wednesday night, and no rain Fri/Sat. Cloudy though. Sunday night could witness thunder rains and Monday, 18th, will be overcast with rains intermittently.
North winds Monday thru Wednesday (6 days forecast ?? Bold attempt, Vagaries !:-) will keep the days around 25/26, but minimum could fall to 8c.

Will review and put up a forecast (with Nepal included) on Friday night, as the previous Vagaries Forecast expires .

Tuesday, April 12, 2011

A2 has moved fairly on line with our predictions. It moved into the sub-continent on Saturday, and thru Tuesday, precipitated rain and snow in the Northern regions.
Places like Kupwara in Kashmir got as much as 4 cms in a day on Monday. The higher reaches did receive snow, but has not restricted movement or caused any disruptions. Qazigund a south Kashmir town on Srinagar-Jammu highway recorded highest 45.8 mm rainfall till 0800 hrs this morning. However, the 300-km-long, life line to Kashmir was through from both sides. Leh recorded a minimum of 1.2c.
Gulmarg received snow and the minimumtemperature on Tuesday was -1.7c. Pahalgam got heavy rain and mild snow, with the minimum skidding to 0.4c today.
Other N.India Rain/snow for Tuesday in cms: Banihal 5.0, Quazigund 4.6, Bhuntar AP & Srinagar 0.7 each, Kalpa 0.6, Dharmasala 0.5, Ambala & Banda 0.1 each.

A2 was active in Utterakhand today (Tuesday). Higher reaches of Himalayas today received fresh snowfall in Uttarakhand while most of the lower areas experienced rainfall bringing cold conditions in the hill state. Both the regions of Garhwal and Kumaon like Gangotri, Yamunotri, Badrinath, Kedarnath, Hemkund sahib and Chakrata received snowfall while most of the lower areas, including the state capital experienced drizzle. Mussoorie recording11 mms of rain and the maximum managing 14.2c as the high on Tuesday.

In H.P. Keylong could manage 8.1c as the high, Dalhousie was 12.6c in the day today (Tuesday),

In the last couple of days, Day temperatures dived by 2/4c in the plains, with New Delhi hovering around 33c as anticipated, and Srinagar moving along estimated lines at around 14/15c in the past 3 days. Shimla was 19c today. The IMD day temperature anomaly map says it all.

Even the nights over a larger region of South, East-Central and East India along with NW India are below normal for this time.

Seems A2 rains were heavier across the borders in N.Pakistan. Muree measured 38 mms while Quetta received 15 mms yesterday, ad many stations between 10-15 mms. The highest temperature in the day today in Pakistan was 38c at Turbat.

In Nepal, rainfall was heavy in the central areas, with Pokhra guaging 24.8 mms today.Kathmandu measured 1.8 mms on Monday, and traces today. Day was comfortable at 27.6c. Comfortable, considering it was tending to shoot in the mid 30s prior to A2.

Now, with A3 ready and rising in the horizon, it seems the wet spell could continue in the North. A3 precipitation will commence in the N.Pakistan and
N.Indian areas from Friday, 15th. thru Monday 18th.
Resultantly, average day temperature could well be in the normal to below normal range for this weekend.

Outlook For next 4 days: Wed13th.April - Fri 15th.April: (Next forecast for weekend on Friday night).Enlargement of Forecast map here.

Precipitation in the Northern regions of Pakistan and in NW India is expected from Friday, 15th. April thru Monday, 18th April.

A well defined Wind dis-continuity line, formed from the induced low (of A2). This could auger well for some thundershowers are likely to pop up from Thurs/Fri/Sat, in interior Mah. and Karnataka. Mahableshwar,Pune, Nagar, Marathwada, and all areas of Vidharbha likely to receive these thundershowers in pockets from Thursday.

This development in the interiors is normal for April, but ,always better off if it is brief. It should not allow the temperatures to remain low, and should allow the heat to actually build up.

IMD Daily Bulletin Quote (12th. April):" A trough/wind discontinuity runs from the induced low over west Madhya Pradesh to south Madhya Maharashtra across Vidarbha and Marathwada with an embedded cyclonic circulation extending upto 1.5 kms a.s.l. over south Madhya Maharashtra".

Due to a high pressure area building up and gaining in the Arabian Sea, coastal regions of Sindh (Pakistan) including Karachi, and Saurashtra region of Gujarat, India, could well expect strong gusty NW winds from Thursday, speeds gushing to 40 kmph.

Mumbai Forecast for Wed/Thu/Fri/Sat:

Partly Cloudy on Wednesday night and Thursday. Days will be warm at 33c, getting a bit more humid from Thursday. Nights will be around 25c.


Scotland shivers after yesterday's 70s, Eastern Europe struggling to warm as northwest flow pushes cold Arctic air south.
Amazing weather...very warm to shivering cold.....full story on Mark's blog.
Mark, your blog puts up U.K. and U.S. stories in a very interesting style..our popularity from India is judged by your web counter !!-:)

Monday, April 11, 2011

50th Anniversary of Human Spaceflight !...those interested see Space News Page.

Global experts meeting this week are likely to forecast a near-normal monsoon for India:

Sunday, April 10, 2011

Monsoon Watch - 1

These reports are my personal views, study and observations. Estimates and forecasts are also my own calculations and views, and may/may not tally with any other estimates. The Monsoon progress as analysed will be discussed and explained in Vagaries.

This annual series is a follow up and chasing of the South-West Monsoon. For now, this series will be chasing and closely following up the actual developments of the monsoon, and analyse its progress. We are not yet contemplating the quantum of rains or the monsoon strength as yet.

Very very briefly, let us first understand, that the "power house" of our SWM is actually based far away in the southern Hemisphere. The main "generating factory" is the Mascrene Highs, SE of the Madagascar coast. The proper formation of these high regions,(1028 mb at least) will boost and create proper SE winds to lash the East African Coast near the Equator, and then turn SW in the Northern Hemisphere.

And the formation of the "Tibetan High" is another factor. An anti-cyclone in the upper atmosphere over the Tibetan Plateau. During the formation stages, there will be thunderstorm activity in the SE parts of Tibet during the months of April and May.

To generate a powerfull SW wind, the cross equatorial flow must be strong and gusty. SW winds (ultimately upto 600 mb levels) then are capable of riding on the warmer Arabian Sea waters and bring cloud masses towards the West Coast of India. In the Bay, similar SW winds are generated, but from SE winds below the equator, just below Sri Lanka.

And to attract the SW winds, again, we need a good proper "seasonal low" to develop in the Sub-Continent. This seasonal low, normally should start forming around Barmer, Rajasthan, by mid April, and at its peak stretch upto Arabia. Seasonal low at its peak, in June, should normally be around 994 mb, and the ridge around Kerala should be 1008 mb. This enables a good gradiant to pull the SWM inland.

In this initial stage, we will observe the basic root and foundation,the initial parameters and the initial seed of the monsoon.

1. Cross Equtorial Winds from Southern Hemisphere.

2. Seasonal Low over India/Pakistan.

3. El-Nino Status.

4. Pre Monsoon Low in the Bay.

1. Cross Equatorial Winds should start forming, and taking shape from mid -April, especially in the South Indian ocean region.

The Mascrene Highs are the main "Power House" of the South -West Monsoons.

This generates the South -East winds, which after gaining strength, cross the equator and become south west. For a proper High to form in the South Indian Ocean, the cyclone season (Low pressures) should completely die down from that region.

Weak signs of initial SE winds forming, but not yet getting organised. Initial forming has commenced off the East African Coast. But the winds are NE above equator. Also, very Strong wind currents are required to be observed near the Eastern side of the Indian Ocean, as the Monsoon stikes the Andaman Sea by mid May.

2. Now, we have just about "normal to below normal" heating in the plains and Southern regions of the Sub-Continent. This is not much of a plus point in the formation, or a quicker formation of one of the important pre- monsoon weather requirement, the seasonal low. The seasonal low, stretch over Arabia thru India, normally starts forming in the Barmer and adjoining regions in the second week of April. Today, the MSL is around 1010 mb in the Sindh/Rajasthan region.

In the "core seed"area, it 1008 mb. (The ultimate low in the core, in June when ready, should be 994mb.). Today, there is a "high" of 1008 mb covering almost the entire Indian region.

The Seasonal Low normally is required to start taking shape for the monsoon by the second week of April.

3. La - Nina factor is favouring SWM as of now. It seems to be weakening, and approaching near normal levels. Forecasted to go neutral by June. Last SOI reading observed was +23. This actually indicates an surviving La-Nina.

• The Oceanic Nino Index (ONI) is based on SST departures from average in the Niño 3.4 region, and is a principal measure for monitoring, assessing, and predicting ENSO. The readings for the last 2 quarters were:-1.4, -1.3 and -1.2. La Niña: characterized by a negative ONI less than or equal to -0.5 C, so today La-Nina prevails.

4. Another pre monsoon seasonal normal requirment is the creation of a low in the Bay by the second week of April. This is necessary to trigger off the flow and formation of lows from the bay.

Progress this year is bad, as the Bay shows a ridge today. High pressure is prevelent in the Bay. No forecast of any low as of now. (in 2009,a low formed by the 12th. of April, and later it intensified into cyclone "Bijli", 2010 had no low till 3rd week of April).

Summary: Parameter; 1. normal, Parameter 2. -ve, Parameter 3. -ve. Parameter 4. -ve.

New Readers, please note, Parameters are normally (every year) considered in MW Series to guage and estimate the arrival cate of SWM, not strength. Time of arrival normally indicated after mid-April.

Next update on 17th. April.

Saturday, April 09, 2011

Come Saturday, and A2 arrives from across the West into India. And sure enough, it is more effective than A1. Advent of Summer will be halted for a few days in the Sub-Continent.

Sub-Continent Outlook for Sunday/Monday/Tuesday:

Vagaries 3 day Forecast Map for 10th, 11th, and 12th April. Click Here for enlargement. Click here for Vagaries Severe Weather Map


Into India, the Northern states of Kashmir and H.P. will get good amounts of precipitation, and snow in the higher reaches of both the states. Snow in Khilanmarg, Gulmarg and Sonmarg possible. Maybe some parts of the Jammu-Srinagar Highway could be affected.
In H.P, Snow possible in Lahaul and Spity valleys and in Keylong and Kalpa.
Shimla, which had a high of 21.6c today, will see the next 3 days cooler by almost 5c, and hills of Manali and Dalhousie will be wet with the day not exceeding 15c.
Srinagar, should also see the day temperature drop by 5/6c from Saturday's reading of 18.2c.

Sunday thru Tueday will be rainy and cold in the hilly states, and precipitation in Punjab, Haryana, Delhi and Rajasthan will cool down the weather in these areas. Few places in Punjab/Haryana/Delhi may possibly experience hailstorms. The plains of Northern India will see the days cooler by 3c as of Saturday readings. With cloudy days, New Delhi will see the day temperatures around 32/33c next 3 days.
Gujarat will be cloudy, but I doubt any meaningful precipitation. Days will be around 40c.

In Pakistan, Saturday, rain/thundershowers have commenced in Balochistan, Lahore, Multan and the Frontier regions.Parchinar recorded 10 mms of rain.Lahore and Peshawar had traces.
On Sunday, there will be precipitation from Northern Pakistan thru Punjab, Balochistan and into Upper Sindh. Larkana and other regions in Upper Sindh will receive precipitations. Cloudy conditions will prevail in rest of Sindh, including Karachi.The city's high will fall to around 32/33c.
Day temperatures in Central and N. Pakistan are expected to be 2/3c cooler than those recorded on Saturday. As rains will bring in cooler weather,
Islamabad will drop from Saturday's high of29c to around 24c next 3 days.

A2 precipitation will be slipping into Nepal from Sunday itself. Thundershowers in all the regions of the country on Monday/Tuesday could be expected. Kathmandu day temperatures should fall into the high 20s from Sunday thru Tuesday.

"The trough/wind discontinuity from east Uttar Pradesh to Marathwada alongwith the embedded cyclonic circulation over west Madhya Pradesh and neighbourhood has become less marked".-IMD Saturday Daily Bulletin.
Now, this has been the cause, (Vagaries has mentioned this earlier) of the Thundersqualls in this "line" . But its weakening, and the embedded low is fizzling out. Hence, I would decreasing rain activity in regions of Vidharbha and adjoinib M.P. from Sunday.
Some left over thundersqualls may shift east into Chattisgarh and Orissa on Sunday/Monday.

Mumbai Forecast:

Sunday/Monday/Tuesday: Cloudy morning on Sunday. Light clouding rest of the days. Days will be around 33c at both centres and nights slightly warmer at 24c. Some Change in weather from Wednesday.

Monsoon Watch - 1 will be up on Vagaries tomorrow, 10th, at 2 pm.

13th June Morning  Mumbai : June summery:  The average daily maximum temperature was  34c.  At night it cooled down to temperatures between ...