Tuesday, May 24, 2016

Posted 24th May Afternoon.
South West Monsoon is Advancing into Maldives...Kahdhoo received 28 mms and Male 14 mms. Winds in Male at around 30 kmph.
Very Gusty winds ( 70 kmph) warning issued for Maldives.

South West Monsoon will advance into Sri Lanka in next 48 hrs.

(As per Vagaries)

Saturday, May 21, 2016

Monsoon Watch --4 (Additional)...
Quantum Analysis is evaluated for the amount of summer monsoon rainfall over Indian monsoon region during June- July....

Forecasting Methods adopted for the Indian Monsoons:

Gowarikar(1989) developed parametric and multiple power regression (MPR) models with 15 predictors for LRF of AISMR, which were later modified in 1991 to include 16 predictor parameters. The parametric model is qualitative and indicates the likelihood of the monsoon rainfall to be excess or deficient.
Thapliyal (1990) evaluated the relative performance of multiple regression, and Navone and Ceccatto (1994) have used 'feed-forward' neural network technique for the prediction of Indian monsoon rainfall with two predictors (500 hPa ridge location and Darwin SLP tendency from January to April). 
The results of a recent work by Krishna Kumar (1997) indicate that a single component accounts for about half of the total variance in the predictors

Most of the studies on LRF of Indian monsoon rainfall were based on empirical or statistical techniques till 2010. IITM, Pune has recently implemented the state-of-the-art coupled climate model, the Coupled Forecasting System (CFS) developed by the National Centers for Environmental Prediction (NCEP), USA. These statistical techniques range from simple correlation analysis to advanced procedures.

Vagaries leans on, and believes in the "Gowarikar Method" with 16 parameters. The results of this old but proven method has been successful. For Vagaries' forecast and analysis made in the "Arrival and quantum Monsoon Watch" series, I combine a few of them alongwith Dynamical models for a personal analysis and estimate. 
15 initial parameters from the months March, April and May are used to analysis and forecast the simulation of Indian monsoon rainfall during June to October. These initial conditions were carefully selected  to span the evolution of both the atmosphere and ocean.

We have to take into consideration most of the 15 parameters (Gowarikar Method) before making an assessment, and these have to be analysed one by one. The prominent among the 15 are , ENSO, March temperatures of North India and East Coast, Himalayan Snow cover till March and SOI to name a few.
Of-course, I am not going to take each and every one of the 15 here, but, derive at an estimate on these basis and on the new model developed. I hope readers of vagaries trust that I have tried my best to estimate as accurately as possible.

Calculating the amount of rainfall, region wise, is of utmost importance, as SWM contributes to almost 80% of the annual total rainfall over India. 
In this article, Quantum Analysis is evaluated for the amount of summer monsoon rainfall over Indian monsoon region during June to SWM withdrawal.

Vagaries' View Point:

The 500 hpa parameter is of importance in April. The mean latitudinal location of the 500 hPa ridge along 75°E in April over India, first identified by Banerjee (1978), is considered to be one of the most important predictors. The mid-tropospheric anticyclone over southern India migrates from 11.5°N in January to its northern most position of 28.5°N during July. 
From October, the ridge starts shifting back southward. A more Northward location indicates better performance of the monsoon and vice versa. It also showed that the negative correlation of the March ridge was more dominant with the monsoon rainfall of the peninsular India, while the positive correlation of the April ridge was more dominant with the monsoon rainfall of Northern India.

ENSO factor in arriving at the rainfall amount is also of importance. The interface is the sea surface: that is where the transfers of water (evaporation/precipitation) 
and momentum occur. An accurate coupling of the fast atmosphere to the slow ocean is essential to simulate the ENSO, which in turn can simulate the interannual 
variability of Indian monsoon. Unfortunately, getting an accurate, or near to accurate forecast of the ENSO for the next 2 months is difficult, with no guarantee of accuracy or performance surety.

We see weak El Nino conditions persisting. But, there is a possibility of a Neutral event occurring as early as July. Now, this would result in recovery of Monsoon condition from mid July or August.(Without a "Break Monsoon"). But I would not endorse the event as yet. I would give it a 50-50 chance. 

We depend also on other parameters.

Normally, Pulses from the Eastern Pacific area, that is S.China sea, would mean depressions and systems originating from the Bay. 'In Situ" systems and systems from the Far east would contribute to the rainfall to the east Coast thru Central India and into Gujarat and even into Sindh (Pakistan). El-Nino, even a mild one, would sort of restrict these pulses, and in fact encourage WDs into coming down south, more South than normal. 
This may persist till  June, and then rapidly the flow of systems should increase from Bay in July.

The performance of Vagaries' Monsoon Watch Quantum Analysis is evaluated for the amount of summer monsoon rainfall over Indian monsoon region during June to SWM withdrawal in 2 phases. (June/July and August/September). 

Why in 2 phases ? Because, I believe it is impossible to give actual Quantum forecast now (In May) for sometime in September...that is 120 days ahead !). I am not competent to give a forecast 90 - 120 days in advance, so Monsoon forecast will be  
1)...For June and July and 
2)... August and September ..this is tentative and will be published in first week July.

A) First 15 days of June sees 
i) Monsoon advancing from Kerala thru upto Central India, and into NE States and West Bengal.
ii) Heat ( Normal to above Normal) in Northern India, and Pakistan. 
Monsoon advances into Central India and North India between 20th - 30th June. 
iii) Monsoon moves into Pakistan around 5th - 12th of July.

B) Mid June to July end, we can see normal rainfall and progress of the SWM in all of  Sub-Continent regions. Weak Nino conditions in the Pacific Oceans will send a few "pulses" to create "in situ" systems in the Bay, and the first 2 months could see around 3/4 noteworthy systems traversing the Sub continent. WDs will be few, hence, we can expect a few systems to track towards Central and Northern India, resulting in good rains in the plains of N.India and Northern Pakistan regions..and fairly good above normal rains in Nepal.

This estimate is based absolutely on the situation as it shows and stands today.  
Things, if and when they change (drastically) will be posted and Vagaries readers will be kept well informed, of any variation in the forecast.  
These are my personal views, and should not be depended upon commercially or otherwise.  They may differ from other models.

Friday, May 20, 2016

Posted 20th May Night:

BB-1, "Roanu", has moved East/North-East, and is located at 19N and 87.6E, tracking away fast. Estimated wind speed analysis average 50 knts (between DVORAK and Automated Intensity). Convective Bands remain weak, and as the System tracks North East, tilting to the East, it will start to weaken from Saturday evening.

Rainfall increasing in Kolkata this weekend. 

All Time High Records broken  on 19th May 2016:

Phalodi 51.0,Churu 50.2,Bikaner 49.5 (previous was in 1914),Jodhpur 48.8,Pilani 47.5
Ahmedabad 48.0  (previous was in 1916), Amreli 46.8
Udaipur 46.4 tied.
Erinpura (India) max. 48.4 ,Sawai Madhopur (India) max. 48.7 ,Jalore (India) max. 48.9 
Source: Maximiliano (Extreme Temps)

19th May Extreme Heat Region:

And Rainfall as on 20th Morning.

Thursday, May 19, 2016

Historical High for India ! Phalodi, Rajasthan, India, records India's highest ever temperature when it recorded 51.0c on 19th May 2016.
Other maximum temperatures in India on 19th May 2016...

1 Phalodi 51.0 °C
2 Churu 50.2 °C (Record...Highest ever)
3 Barmer 49.5 °C
4 Bikaner 49.5 °C 
Hottest in Gujarat: Ahmedabad (Highest ever) and Deesa at 48.0c. Hottest in Maharashtra: Jalgaon 46.6c.

Pakistan Met Department announces 52.2c in Larkana on 19th May 2016..
Other Pakistan Highs on 19th:
1 Jacobabad         51.5 °C
2 Bahawalnagar 50.0 °C
3 Sibi                         50.0 °C
4 Rohri                 49.0 °C

Position on Thursday 19th Night:
BB-1 is positioned at 16N and 83E, around 240 kms South West of Vizag, has turned track to East/North East. It is now tracking along the North West periphery of the STR. Will track North East.
The only signs of it being a cyclone (Roanu) is the Core pressure estimated at 985 mb and core winds estimated at 50 knts. With a decreased deep convection around the centre, nor any specific convective band seen, and with a persistent vertical shear, it does not resemble a cyclone in the satellite image. 
"Roanu" will keep its strength, or still deepen a bit, before weakening from Saturday.

Wednesday, May 18, 2016

Posted Wednesday 18th May Night:

18th May 2016...The Highest ever temperature (Official and reliable) for India has been recorded at Phalodi (West Rajasthan)...50.5c.
This is a record, and the Highest ever for India. 

(India's Highest ever...Officially they record 50.6c at Alwar...But reading is doubtful...even as per WMO......The station was open few months before and during 1956 it was giving too high maxima 5-6C higher than surrounding stations, than later it got normal. In early May 1956 it was not so hot, but slightly above the average, we can say like a normal day in early June, but not at record levels.)...From Vagaries Extreme
see also here

18th May Maximums:
Churu followed with 49.1c, Jaisalmer 48.8c, Barmer 48.1c. Hottest in Maharashtra on Wednesday was Akola at 47.1c, and Hottest in Gujarat was Surendranagar at 47.8c. Idar followed with 47.6c, Gandhinagar saw 47.0c  and Ahmedabad was hot at 46.9c.   
New Delhi Palam was 46.4c.

Across the border in Pakistan, it was sizzling with extreme temperatures....
Larkana in Sindh saw an unimaginable 52.0c,( Minimum at Larkana was 33.2c), Sibbi and Mohen-Jo- Daro saw 51.0c, Jacobabad and Padidan 50.5c...to mention the "above 50s" only.


BB-1, a deep depression is located at 14.4N and 81.4E, 160 kms East of Nellore on Wednesday evening. Estimated pressure is 993 mb and core winds estimated at 40 knts. Tracking NE.



The system has dumped around 200 mms rains at Chennai in the past 2 days..

Max / Min temp in c : Coimbatore 31 / 23 , Puducherry 28 / 25 , Madurai 36 / 25