Friday, April 30, 2010

Continuing from yesterday's blog...
Due to thunderstorm activities over many parts of the sub-continent,, maximum temperatures have fallen by 4-8°C over parts of west Madhya Pradesh, Maharashtra and Karnataka and by 2-3°C over parts of Punjab, Rajasthan, Uttar Pradesh and Rayalaseema. (Day temp map from Univ. of Cologne attached). The fall into the late 30s is very visible here.
The highest in Pakistan today was recorded at Nawabshah, 44c and 43.4c in India,at Chur (Rajasthan) and Daltonganj.
Hence discussed in the blog yesterday, the W.D. has had some effect on the day's heat. And, I expect another 2/3c fall in the day's heat in the next 2 days.
Meanwhile, day temperatures have also dropped in Maharashtra, with Washim, recording the highest today of 42c. This fall is attributed to the light rains all over the state, as a result of a trough running from W.Bengal to the South-East Arabian Sea.

And, to the contrary, Mumbai has become worst off after a drizzle on Friday morning. S'Cruz was high at 37c, and the humidity factor was unbearable as it was partly cloudy in the day.
I do not expect this rain in Maharashtra to last beyond Saturday.

Thursday, April 29, 2010

W.D. may Lessen Heat Temporarily:
With a moderate precipitating rains/duststorms in Pakistan, I see the system crossing over into India by the 30th.

Result: Fairly good rains/hailstorms in the North-West/North and Central regions of India.
And with some rain in South Vidharbh today (29th.), the scorching heat of Vidharbh now underway, will lessen with the passing of the W.D. from tomorrow.
 Expect the highs in Vidharbh to come down from 45c to 41/42c.Since the W.D. is moderately strong, the days will surely get cooler by 3/4c starting 30th. North Indian states, Gujarat and baking inintense 43/45c temperatures, can expect some relief,albiet for a few days only.

Today, the highest in Asia was 45c at Nagpur (India) and Nawabshah(Pakistan).
All this relief is temporary for a couple of days, till the passing of the W.D. The heat is immiediately following up in the rear of the system.
Mumbai was a sweaty 35.5c (+3c), and cloudless.(Though I was expecting some clouding today). Mahableshwar couln't be any better too, as the day was hot today at 33c with no relief at night,20c. Thane, too was scorching at 38.8c (AWS reading).

Monsoon Watch - 4

The parameter of utmost concern to me now is the Bay factor. The consistently -ve factor in the first 3 MWs.
The latest winds in the Bay show a strong current rushing Northwards along the East coast of India, into the trough in sub-Himalayan West Bengal. The North-West flow of winds into the Myanmar coast also exists. Thereby, to some extent, the hitherto prevailing "high" is somewhat breaking up.
Also, the SST in the Bay is quite conducive to host a low anytime now. Like previously mentioned, a low, according to me, should have normally formed by 15th. April. Infact, last year we had a cyclone in the Bay in April. A delay here can effect the Bay branch of the Monsoon. Now, the delay in the formatiion of the wanted low is due to the trough running along the North-Eastern states, which has caused very heavy rains there. Moisture laden winds are gushing into the region, causing heavy rains.
Now, according to ECMWF forecasts, and other models,no low is predicted in the Bay till the 6th.May at least. Indicator :-ve

The Seasonal Low in the Thar Desert is deepening gradually. As on end April, a pressure of 1000 mb in the central core region around Barmer is normal.(See Thai Met Dept Map).Now onwards, the core should expand, and stretch into the West, into Pakistan, and within a week further West. Finally, by June, the low has to stretch from India to Arabia, with its core centre (994mb) somewhere near Jacobabad. The intense heat in the sub continent is an useful aide to this formation.
Also, further heavy moisture inflow from the North-West winds into Kerala and South Karnataka coast may prevent a proper gradiant to form to give the Monsoon a final momentum and push along the west coast. During end of May,the low in the North (Rajasthan/Sindh) may be normal at 996mb,but the 1008 mb required off the Southern tip may not materise on time. And that is a must for creating a pull Northwards for the Monsoon.Still, we have the month of May for the situation to "cool off", or rather "warm up" along the south- west coast. Indicator :Normal.

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 developed upto the Equator, and are gaining strenght over Sri Lanka.(See COLA/IGES Map) 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. Indicator: Normal

The cross equatorial flow,is surely picking up. A very crucial factor this one. The Mascrene highs are establishing and winds hitting the East African coast are getting stronger, and the Somali Current is getting defined. The lacking factor is the cross flow south of the Bay, that is, the Eastern parameter.(See Aust. Bur. of Met.TXLAPS Wind chart attached). The Bay branch should be getting stronger by now, but lacks the momento. But, a push is there in the offing. As reported by the Australian Weather buraeu "The latest guidance suggests that an active MJO event will develop in the western Indian Ocean over the coming week or two. In response to this, we would expect to see an increase in convective activity over the northern Indian Ocean, although is unlikely to trigger the Indian Monsoon onset this early in the year."
However, I feel, this will be a good booster for the Bay branch of the Monsoon. Remember, the due date for the Monsoon in the South Andaman Sea is May 12th. Indicator: Normal.

The cyclone in the Southern Indian Ocean has dissipitated, hence there is no longer any hindrance now for the ITCZ to start moving North. Situated at 5S, it should normally cross the equator around 10th.May,for a proper setting of the Monsoon in both the branches.

El-Nino: According to the latest report from the Australian Weather Bureau, "the majority of ENSO indicators have now dropped below El Niño thresholds. The cooling of the tropical Pacific Ocean ..has resulted in trade winds and tropical cloudiness returning to normal."
But, my estimates show that a weak El-Nino is still hanging around.
Regions Previous Current Temperature change
(2 weeks)
Nino 3        0.3°C cooler
Nino 3.4    0.1°C cooler
Nino 4        0.1°C cooler

While checking out all the other parameters, we cannot neglect this very important event. Still, as we have time in hand, and if all goes well, SST can start declining , and come to neutral levels by May end. SOI indicates this favourably, as it is now gained a few notches up to +15 on April 25th.. Very very encouraging. In fact,sustained positive values of the SOI above +10 may indicate La Niña episodes.
Indicator: +ve

Really, we are still at the mercy of Nature and Providence in spite of our so called "developments."
Conclusion: As of today, there seems to be a slight delay in the Bay branch of the Monsoon. And, the Arabian Sea branch needs a little trigger to get going in May. Maybe a little less rain in the first half of May for Kerala? Arrival date should be around 1st. June for Kerala.(This Monsoon chase is my personal view, and my personal analysis and deciphering is done as per my assumptions).

Tuesday, April 27, 2010

Pre-Monsoon Rains and Indian Heat:

The 2nd. half of April has seen Pre-Monsoon rains lashing the Southern and Eastern regions of India.Though today, after a long break, we see the rains relenting to some extent in the East, but the Southern state of Kerala continues to enjoy the "rain bounty", and much to the relief of the state, the temperatures have come down considerably, after record breaking 40 degree heat in the state.
The North-Eastern States had a fairly good spell of pre-monsoon rains, as mentioned. Traditional wet spot, Cherrapunjee, has recieved as much as around 3300mms of rain to date in April ! And that is 2588 mms above normal! Heading towards the 5000mms mark by May end ?? Passighat has recieved 926 mm, and is in excess by 626mm!!
And most places in the North-Eastern states are 100% to 200 % in excess rainwise.

In the South, Kerala and Karnataka have recieved, and continue to recieve the pre monsoon heavy thundershowers.Though T.N.did not get much rain, and would not normally, Kerala and specially coastal Karnataka is in excess. Thiruvananthapuram, as on 27th. has recieved 299 mms of rain, (for Mar/Apr, but almost all in April), excess by 163 mms. Now this total, is far in excess of rains recieved in this city, in April, in the last 15 years.

Good, substantial inflow of moisture into the North-East, due to a trough running into the North-East Bay is the cause of this rain there. And, a good flow of West winds, into the South Western coast of India, has precipitated rains along the coast.It is resultantly breaking up the "high" there.

Is all this now going to have a bearing on the advancement of the Monsoon? Is the heavy rain in the North-East going to effect the Bay branch? Cannot say now, but if the pre monsoon rains continue beyond, say, 10th. May, we may find some change in the arrival dates. Maybe either way, if the pre monsoon spell converts itself into a regular south-west flow.
We will discuss this as and when, with proper analysis in the Monsoon Watch series.

Todays day temperatures were above normal in the central region. The 2 IMD maps show the extreme heat wave in the centre of India. Highest today (27th. April) in Asia was at Chandrapur, Maharashtra, at 45.2c.with the night at this place recording 30.8c. Nagpur and Gwalior followed at 44.5c.
The map shows India in a clear North-South divide,weather wise. The southern temperatures were generally below normal, while the central region shows very high abnormality, and the rest of North/North-West India fairly above normal.

The Climate Prediction Centre (NOAA) deviation map of last week shows that the maximum heat was in the Rajasthan region last week. Anyway, a major portion of the sub-continent was in an "above normal zone" throughout last week.

Monsoon Watch - 4 will be up on the blog on Friday, 30th.April.
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Sunday, April 25, 2010

Range of temperature variation in India :

An interesting analysis of the temperature range variation in India, from the Himalayas down to the heated plains of Central India.This is for Sunday, 25th. April.
Hottest: Ramagundam, Chandrapur, Jamshedpur: 45c
Hottest Metro, Delhi:39c
Hottest Hill station, Mahableshwar: 33c

Coolest in plains, Amritsar: 20c
Coolest in Valley, Srinagar: 7c
Coolest in Sub Himalayan Hills, Kalpa (H.P.): 0.5c
Coolest in Himalayan Region, Chushul (Ladhak):-18c.

Forecast for Mumbai: Days will remain hot and stuffy till Wednessday. Expect cloudy and very stuffy weather, with high humidity on Thursday/Friday. A little rain or drizzle is going to make it a miserable night on Thursday. An uncomfortable and "unfriendly" week, as it will be sweaty and humid.
When is the monsoon coming? Well, as per our readers poll, 52% say between 25th.and 31st.May. However,19% say after 5th. June. ??? Lets hope majority prevails !!
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Saturday, April 24, 2010

Monsoon Watch - 3
Bay of Bengal : Indicator: -ve

Continuing from MW-2, I am now worried about the "Bay of Bengal" low pressure parameter. I feel, 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.
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 indiacate a "high" trying to establish itself. only +ve sign of a quick formation is that the SST is conducive. Conducive , 1)as I see winds getting Easterly, (See chart) to start with and breaking up the high pressure area, and 2) the Bay sea temperatures heating up around the Andaman Islands.

Sub-Continent Seasonal Low: indicator: ++ve
On the other hand, the sesonal low in the Thar region is getting into shape fast, thanks to the intense heat wave.True,the entire sub-continent region has suffered a heat wave, but the gains are much more. The central core pressure around the Thar desert region is now 1000mb (994mb required by June begining). And , as per the scheduled development, a proper gradiant is well on its way in the making.
The line of dis-continuity is shifting back to its normal postion, in the centre of the Southern Peninsula region. Out breaks of pre- monsoon thundershowers are expected next week in thie southern states and South Maharashtra.

Cross Equatorial Winds : Indicator ++ve
The cross equatorial wind flow, has picked up superbly in the Southern Hemisphere.Winds,getting stronger,have now started hitting the East African coast, and a re-curving Northwards of the winds, on the Kenyan coast,is seen.
As a result, we are seeing the Somali Current building up now.
Cross winds in the Eastern Sector (Bay) are getting strong too, and are re-curving.
That means, a high pressure region, the back-bone of our Summer Monsoon, is starting to form down in the Southern Hemisphere, off the Madagascar Island, and in the mid South Indian ocean. We have to observe this, and if no low pressure forms there till end of April, the ITCZ can start moving North.

Amidst this, a cyclone, "Sean" has formed off the west coast of Australia. Now, this would keep the ITCZ intact and keep it firmly stuck at around 5S. But, the forecast states the cyclone to move east, and dissipate within 72hrs. That's good news.
The positive news from Australian Weather Bureau; "The risk of tropical cyclone formation in the Australian region remains a very slim possibility for the end of April, although is becoming increasingly unlikely."

El-Nino: Indicator: Same as Last MW.
 El Niño is present across the equatorial Pacific Ocean. The latest weekly SST departures are:
Niño 4 0.8ºC
Niño 3.4 0.8ºC
Niño 3 0.8ºC

Niño 1+2 1.1ºC
For El-Nino Factors in detail, see Link
The monthly SOI for March was -11, but the 30-day Southern Oscillation Index [SOI] to 18 April was +10. Hence, the SOI, animportant factor for the El-Nino, has stayed +ve.

SST in the El-Nino 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 El-Nino coming to normalcy, the set back would be, weak rains in June, picking up in July.
snippets on twitter: @rajesh26

Friday, April 23, 2010

IMD "forecast"

The much awaited IMD forecast is out. All and sundry waited, for this crucial announcement, while millions of farmers depend on an accurate estimate.

IMD forecast turned out like a deflated baloon.Vague hazy unclear and too general.Its a1959 type frcst.not region specific at all.
With super computers, and other facilities, we expected a more specific forecast.Which region of the country's vast areas will be deficient? Or which will be surplus? This IMD forecast means, if say, Gujarat is -10%, and sa, Karnataka is +10%, the prediction is correct. But what about the drought in the deficit region??
The country is too vast to give such a generalised estimate!
The irony: Next forecast straight in June now !
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Heat Wave Abates Partially:

A western disturbance has created a dust storm over North-Western India, the haze from which hung heavy over Rajasthan, Haryana, Delhi and west Uttar Pradesh. A superb Satellite image (NASA) of this dust is attached.
As a result, after a week-long spell of blistering heat, people of the Northern/Western states got some respite, as temperatures across the states dipped on Thursday.

Heat wave has abated in Punjab, Haryana, Delhi, Rajasthan and Uttar Pradesh. Day temperaturesare down by aabout 2/3c, and now the highs hover around 40/42c in North-west India. Even the nights, which had gone over 30c in many a regions, and were as high as 33c in Hissar (+14c), are now around 26c levels (comfortable??). The normally cooler regions of Kashmir and H.P. have also "sobered" down, with Srinagar recording a high of 15c, and Simla 24c on Thursday.
Some lessening of the heat was felt over Pakistan also. The highest there coming down from 47c to 43c yesterday at Nawabshah.
But the heat is not over as such. Heat wave conditions continue to linger on over parts of Central region,East Uttar Pradesh, Bihar, Jharkhand and Orissa. The highest maximum of 45c was recorded at Bankura in W.Bengal. (IMD Map).

Forecasts indicate the arrival of another W.D. in a day.
The maximum temperatures are expected fall by another 2c over many parts of northwest, central and east India during the two days.
The rainfall pattern last few days was restricted to the 3"corners " of India. The North-East, where Cherrapunjee has recieved very heavy rainfall. 266cms from 1st.March till date ! Then the extreme North, due to the W.D. and the South.

Meanwhile, the rains in the south have lessened , as the wind dis-continuity line shows fragmentation. Though the trough from southeast Vidarbha to Comorin area across Andhra Pradesh and Tamilnadu in lower levels persists, the thundershowers will be persisting on a lesser scale next few days in Karnataka and Kerala. I expect the trough line to shift to the southern peninsula after 2 days, and consequently. a slight increase in thundershowers in Karnataka, Kerala and more so along the coast. Maybe creeping into South Maharashtra coast from Monday.
Monsoon Watch will be put up on 25th.April.

Tuesday, April 20, 2010

Not only the days,Nights too continue to get Hot in North India.

Some of the Minimum temperatures over 30s, with departure from the normal,on;
Hissar 33 (+14), New Delhi 31 (+10)

Jaipur AP 30 (+9), Chandrapur 30.5, Gwalior 31.9,
Khajuraho 30.8
Yes. These are the Lowest temperatures for the day !!

Monday, April 19, 2010

Nights in the Indian region now baking in Heat Wave:
As the Heat Wave continues in the Sub-Continent, I see  new "highs" in the minimum temperatures.In the chart from IMD for 18th.April, if we observe the lows, they were as much as +12c above the normal in Jammu, and +11c above normal in Hissar.Many other places report minimums at +4 to +8c above normal.
Jammu  Max:38.7 (+06)    Min: 30.6 (+12)
Hissar   Max:44.1 (+07)    Min:30.8 (+11).    
Yesterday, on 18th, the highest day temperature of 46.5c was recorded at Daltongunj. And several places were at 45c.

My forecast for Monday thru Wednessday would be: North would see some rain in the most Northern hilly states, due to a weak upper level W.D. For the South, rain/thundershowers in southern Karnataka coast, not much rain inland for Karnataka next 3 days.Bangalore may not recieve rain thru this period. Rain in Kerala will be fairly good, but diminishing on Wednessday.I estimate the rain to lessen as I see winds along the South-West coast turning North, indicating a high forming in the Arabian Sea.
The North-East rains should continue thru this period (Monday thru Wed.). West and Central regions will be dry and hot. Maximums of 45/46c could be recorded in Rajasthan and Vidharbh.

The Eyjafjallajokull eruption:
The damage caused by Iceland volcano "Eyjafjallajokull," could be far more damaging than is being reported.
The Forecast for the ash cloud:

Photographer Martin Rietze got to within 250 metres of the lava fountains to capture his stunning series of images:



Lava spurts out of the site of a volcanic eruption at the Fimmvorduhals volcano near the Eyjafjallajokull

Friday, April 16, 2010

Feeling Hot Hot Hot!!

With a Day temperature Map like this )of 16th. April), I would say whats the next after Very HOT !!
Just look at the 44s and the 45s. Generously distributed, all over, with a "tinge " of 46 hear and there ! Spot your city, and see the temperature.

And, I have read of a 50c today, 16th, in pakistan at Rohri. Phew ! Yet to confirm as authentic though, but i don't doubt the source.
Hill stations like Mahableshwar and Dharamshala were 35c today, and Simla was 28c. These are 4/5c above the normal. See variation Map, all above normal !!

Only consolation: Thundershowers have started cropping up in the peninsula region.
South Maharashtra, Karnataka and Kerala have recieved heavy and violent storms on Thursday and Friday. With this heat, I think more to follow next 2 days.
For the North, relief in sight with an "moderate" W.D coming from tomorrow. ( IPL match in Dharamshala may be affected day after tomorrow).
For Monsoon, read MW-2 below.

Monsoon Watch - 2

The Monsoon Rains performance this year is very very critical for India. Its economic growth hangs on the agriculture output this Kharif Season, and the water table needs a boost after the extermely poor Monsoon last year. (Mumbai has very limited water reseves now). IMD has optimistically stated that " 2 sucessive Monsoon failures are very rare."
Lets really hope so.

1. 4. El-Nino factor, is fast turning +ve,change from last week :
Nino 3 +0.8 +1.0 0.2°C warmer
Nino 3.4 +1.0 +0.8 0.2°C cooler
Nino 4 +1.0 +0.9 0.1°C cooler
Sea surface temperatures in the tropical Pacific have continued to cool over the past week, though still above El Niño thresholds. Temperatures in all the main ENSO monitoring areas are now less than 1°C above normal, a situation which last occurred in late September 2009.
The decline in the current El Niño event is consistent with which suggest Pacific Ocean temperatures will cool steadily over the coming months, and climate model predictions suggest returning to neutral levels by summer 2010.
The SOI also became positive on 8th April, first time after Sept last year. The latest Soi reading is a healthy +3. A +ve SOI means weakening of the EL-Nino. Lastyear we had a _ve SOI from June thru December.

2. The only +ve factor from the previous MW discussion, the quick formation of the Seasonal Low due to the intwnse heat wave in Central and Northern regions of the Sub-Continent, continues to be favourable. Into the 3rd. week of April now, the heat is relentless. Highs of 46.4c (Ganganagar) today (16th.April), and 46c in Akola and Hissar, has mercilessly baked the North/Central and Eastern region, and Vidharbh, in Central India was scorching at over 45c, at Chandrapur and Nagpur. Across the border, Nawabshah overtakes at 47c on Wednessday last week.
Augurs well for the formation of the Monsoon Low, and creation of the gradiant required to pull the monsoon winds into the scorched landmass. As on today, the lowest pressure, in the Thar Desert region is at 1002 mb. and this "low" tends to extend into the Indian heartland. As mentioned, it reaches a low nadir of 994 mb in June, and with 1008mb in the Soutrh Arabian Sea, a perfect gradiant is created to attract the south -west winds.

3. But, last week , the Monsoon winds, which originate from the Southern Indian ocean, cross the equator to become south -west , were still weak, and not developed . Now, we find, the South-east winds (below the equator they are SE), have organised themselves in the region south of the Andaman Sea. Currents are seen off the Sunmatra coast. And that is exactly where the start should be. Also, strong SE winds are seen along the Kenyan Coast.
The 3 high pressure zones in the South Indian Ocean, between Madagascar and Australia, have been observed, and the "Power House" of the Monsoon winds is on stream. Almost on time, as per schedule.

4. Another factor, which helps the winds gain strenght, and bring more moisture into the Indian landmass, is the sea temperatures on both sides of the Peninsuala. Optimum (warm) temperatures will hasten and create more clouds, and help in faster forming of the lows from the Bay. This parameter, is almost "normal" and favourable as on date. And I have put up the SST of last year on date to compare the and show the better position this year.
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. The ITCZ, is in its "normal" position. Its movement northwards, to bring the existing SE winds above the equator should be observed around 1st. of May. At least not till cyclones are active in the Southern Hemisphere.

6. The 200hpa Jet Streams, required to be Easterlies during the Monsoon are not yet organised. Starting their Northward movement from 8N, they should be moving "up North" by the end of April, to facillitate the lower Monsoon winds.
Summary: 1.Getting +ve. 2. +ve. 3.Getting +ve. 4.Normal. 5.Normal.
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Thursday, April 15, 2010

Heavy Thundershowers in Karnataka and Coastal A.P.yesterday.
Heat wave severe in H.P. with Simla at  high of 28.2c,( +9, and All time for April 29.5c). And all India high of 45.5c at Sambalpur (Orissa).
Nawabshah records 47c in Pakistan.

For Snippets, also follow on Twitter @rajesh26

Tuesday, April 13, 2010

Heat Wave in Indian Sub-Continent:
The Indian Sub-Continent specially the central, North-Western and Northern regions,has been in the grip of a severe heat wave since the begining of April. The Temperature Anomaly Map shows the North-West in severe Dark Red heat, and major portions of the Sub-Continent in the red, save the South.
April has seen some "severe above normals". A few of the "Hot Spots" of the last couple of days:
Delhi: Palam 42.8c. S'Jung 41.6c    West Bengal: Daltongunj 44.6c, Bankura 43.8c.
 Orissa: Jharsuguda 45.2c, Titalgarh 45.2c.    Bihar: Gaya 44.8c.     U.P: Sultanpur 45.2c, Varanasi 45c.
 Gujarat: Bhuj 43.7c, Ahemdabad 42.4c, Rajkot 42.2c.
 Maharashtra: Chandrapur 45c, Nagpur 45c, Pune 41c, Mumbai 38c.
    Pakistan : Nawabshah 47c.
The Day Temperature Map of Tuesday, 13th, does not show much relief, with 45's scattered all over the Central and East India, and in Pakistan.

The heat is attributed mainly to the North-Westerly winds sweeping the plains of Northern region, and the absence of a real effective W.D. The W.D. is absconding due to a ridge of High sitting firm on the North-Western region.

Meanwhile, just got news (10pm Tuesday) of "very good " rain, or rather thundershowers , from Banglore. What a relief! I understand almost the entire state of Karnataka has recieved good rains this evening, anf the "line of wind discontinuity" has been a boon to the region.

Saturday, April 10, 2010

Monsoon Watch - 1

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 how much it is progressing. We are not yet contemplating the quantum of rains or the monsoon strenght as yet.
These reports are my study an obsevations and the progress as analysed will be discussed and explained in this blog.
In this initial stage, we will observe the basic root and foundation,the initial seed of the monsoon.
1. Seasonal Low over India/Pakistan.
2. El-Nino Status.
3. Pre Monsoon Low in the Bay.
4. .Cross Equtorial Winds from Southern Hemisphere.

1. Currently, the day and night temperatures are above normal and extremely high in the Sub-Continent. Yesterday, 9th. April, saw Nawabshah (Pakistan) reach 47.0c.
And, the 45c mark has been touched in India today, 10th. April. 45c at Jharsuguda. I estimate it is about 15 days early than what I would consider normal. Our blog poll showed 47% vote for 45c before 15th. April.
Today's highs in the Sub-Continent: Putting up the list down till 44c, which too is quite a number !
Jharsuguda 45°
Jamshedpur 44.6°
Pbo Raipur 44°
Nagpur Airport 44°
Gaya Airport 44°
Now, this heat should be a plus point in the formation, or a quicker formation of one of the important pre monsoon weather requirment, the seasonal low. The seasonal low, over Arabia thru India stretch ,normally starts forming in the Barmer and adjoining regions in the second week of April. Today, the MSL is around 1002mb in the Sindh/Rajasthan region. (The ultimate low, in June when ready, should be 994mb.)
The Seasonal Low normally is required to start taking shape for the monsoon by the second week of April, but has started early this year.

2. The El-Nino is gradually weakening, though it is required to neutralise before the Monsoon date.
However, the UN agency said that it could not rule out the possibility that El Nino would persist beyond mid-year.
"The most likely outcome by mid-year 2010 is for the El Nino event to have decayed and near-neutral conditions to be re-established across the tropical Pacific," the World Meteorological Organization (WMO) said in a statement.
"Even during the decaying phase of the El Nino expected over the next few months, the conditions associated with it will continue to influence climate patterns at least through the second quarter of the year," it added.
Some sources admit that El-Nino might linger on till June .
Then,monsoon rains and will be back to normal in early July if the El Nino starts to neutralize in June,

3.Another pre monsoon seasonal normal requirment is the creation of a low in the Bay by the second week of April. This is necassary 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. (Last year,a low formed by the 12th. of April, and later it intensified into cyclone "Bijli").

4. Cross Equtorial 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 strenght, cross the equator and become south west.
Initial forming has commenced near the East African Coast. But the winds are not organised. Stronger 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.

Summary: Parameter; 1. +ve, Parameter 2. -ve, Parameter 3. -ve. Parameter 4. Normal.
Next update on 18th. April.

Thursday, April 08, 2010

Extreme Heat in central India:

On Thursday, central regions of India experianced extreme heat with Akola topping at 44.7c. ( No, I don't take it as 45c, and the poll remains open).
Several cities in Central and Western India are now in the 42~44c range. Most of the Indian region is above normal.And the maps of today's temperature and departure show it all.
Highest in Asia/India: Akola 44.7c. Highest in Thailand: 44c Tak. Highest in Pakistan: 43.0c at Nawabshah.
A noteworthy point: Nawabshah had a range between day & night temperatures of 27 degrees c ! High of 43c and a low of 16c ! Thats quite a range, I have no records for that, but seems the highest range between day & night I've seen !

Current Weather in Mumbai (Thursday10 pm Local Time): Thunder/Lightning and Drizzle. Some moderately high clouds, with cloud top at -30c, and very light SE breeze. Temperature @ 10 pm: 30c.
Unexpected though welcome, for Mumbai, after a day's high of 37.8c at Santa Cruz. No, it was not forecasted, and was quite sudden. Maybe due to moisture incursion from the Arabian Sea towards a weak trough line near central India, and generation of a lot of heat. As per AWS readings, Thane was 43c today (Thursday), alongwith Karjat also at 43c.
Though,on Friday, I expect cloudy weather ,no rain as such, and the high of around 36c. Nights are going to be very stuffy, with the thermometer not going below 28c.

Tuesday, April 06, 2010

El-Nino Update:
And Monsoon Watch Series will be resumed on this Blog from April 11th.

Giving an urgent update, as I see some good developments of it waning now.
The decrease in trade wind strength over the Pacific, mentioned in my blog in the last update,and which stalled the decay of the current El Niño event, appears to have ended. Trade winds have strengthened over the Pacific last week, leading to a slight cooling of the ocean surface temperatures in the central Pacific.
The recent decrease in trade wind strength over the Pacific, which stalled the decay of the current El Niño event, appears to have ended. Trade winds have strengthened over the Pacific during the past fortnight, leading to a slight cooling of the ocean surface temperatures in the central Pacific
The current (31 March) 30-day value of the SOI is −12, while the monthly value for February was −15.The 30-day Southern Oscillation Index [SOI] to 4 April was -5.
Most international computer models are predicting a return to neutral conditions during the next 2 months.

Meanwhile, we read of the effects of the current El-Nino in Eastern Asia regions.
Vietnam faces a power shortage this year as a drought threatens production of hydroelectricity.
Serious dry weather nationwide is significantly hurting water levels in reservoirs used for hydropower production, the government said in a statement on its Web site.
Dry weather caused by the El Nino has raised concern that rice crops in the Philippines, Thailand and Vietnam and palm oil in Malaysia and Indonesia may be reduced this year, spurring food inflation. Vietnamese.
The El Nino weather phenomenon, characterized by warmer sea-surface temperatures across the equatorial Pacific, can cut rainfall in Asia.
For the Indonesia regions, if the El-Nino weakens, inter-monsoon period would set in soon with rains expected in May and June.

The highest temperature in India today (Tuesday) was 43.8c at Nagpur. Nearing our 45c poll mark now! And highest in Pakistan today reached 43c in Nawabshah.

Saturday, April 03, 2010

Keeping a watch on the El-Nino:

•El Niño is present across the equatorial Pacific Ocean.
•Sea surface temperatures (SST) are more than 1.0ºCabove-average across much of the central and eastern equatorial Pacific.
•Based on current observations and dynamical model forecasts, El Niño is expected to continue at least through the Northern Hemisphere spring 2010.
The recent decrease in trade wind strength over the Pacific, which stalled the decay of the current El Niño event, appears to have ended. Trade winds have strengthened over the Pacific recently, leading to a slight cooling of the ocean surface temperatures in the central Pacific.
Overall, Pacific Ocean temperatures still remain at levels associated with an El Niño event, but are again cooling in line with expectations. And,El Niño breakdown has resumed.
Computer models suggest Pacific Ocean temperatures will cool steadily over the coming months, returning to neutral levels by the summer.
As per NOAA, " So far, declines in strength have only been modest; Further decline in strength is expected over the next few months, but considerable uncertainty remains regarding the timing and rate of decay.
"It is however important to recognize that impacts of the current El Niño are expected to continue to be felt in many parts of the world through at least the second quarter of 2010.
The situation in the tropical Pacific will continue to be carefully monitored."

I will resume my annual "Monsoon Watch" series from 10th. April, and will coincide and include the El-Nino progress therein.

Temperatures in India, have tapered down to "slightly above normal " levels, from April, as shown in the IMD maps.
Both, highs and lows are now marginally above normal over the country, but for a small region in Central Maharashtra, whwere the nights are below normal. (Nasik and Pune were at 17c.).
Highest in the country on Saturday was 42.6c, at Jamshedpur. This was the highest in the sub-continent. Highest in pakistan was 40c. Poll still open !

Thursday, April 01, 2010

Hot March For Sub-Continent.
IPL Hill Venue heats up !
This is how march has been for the Sub-Continent ! We had a HOT March.

Central India, Maharashtra and Northwards have been above normal, most of North-West ern regions have been hot, that is temperatures were in the range 41c-43c, nearly 7/8c above normal. And some pockets saw high day temperatures of 10/11c above noraml. Instances of such high departures have been mentioned in my previous blogs.
Come April 1st. and..things have simmered down a bit. The highest today was 43c at Nawabshah (SIndh) and 42c at Nellore and Jamshedpur in India. The rest of the central regions were between 35c and 38c today.
But do not expect days to remain subdued for long. Now into April, days can be expected to start heating up again from next week, more so in central and north-west India. Gujarat, Vidharbh, M.P. and Rajasthan should see over 42c early next week, and Delhi, Haryana, Punjab and west U.P. should reach 41/42c by next week.
H.P.which was bearing the brunt of the heat wave, with places at 10c /11c above normal, and Dharamsala (an IPL hill venue) having shot up to 31.5c (+10c) last week, is a wee bit better off now at 29c today. Simla has cooled down from a high of 25.5c to 23c, and the coldest place in the state, Kelong was today at 1c as the minimum.
Meanwhile, the easterly wave mentioned in the previous blog, though weak, has precipitated some rains in T.N.,along the coast. I expect the rains to remain somewhat frequent in T.N, coast amd interior, into the first week.
Still, our blog poll result remains open today. No city has reached 45c this year as yet. So, option of 31st March is over. There were no votes for that anyway. But, a few cities were within reach during last month's heat wave, having reached 43.5c then.

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