Major Weather change expected in Central,Southern India

METD WEATHER
Akshay Deoras
Severe Weather Forecaster,

Nagpur recorded a minimum temperature of 6.3C on Wednesday,26th Dec 2012. However there is going to be a major weather change in the coming days in India

Bay Low Pressure system-

Attached is the 850mb GFS Map of Base 00z,28th Dec.

One can see a broad patch of anti-clockwise winds with green shading across Sri Lanka. This is the Bay low pressure system which shall pump moisture across mainland of India resulting into precipitation in the southern states-

Above is the +48hr precipitation forecast showing rainfall across Kerala,Tamil Nadu,Coastal Andhra Pradesh and some interior Karnataka.
The precipitation shall increase across Karnataka coastal areas eventually spreading into Goa on the New Year eve

If does appear that Goa may get light rain spell on 30th Dec 2012 and some on 31st Dec as well. The meteograms aren't agreeing however..

As the Bay system progresses westwards, a High Pressure system is expected to develop across Orissa at the 850mb level which shall steer the moisture and push it Northwards.

Minimum temperature in Central India will be rising nowonwards as the direction of the winds have changed.

The precipitation will spread into Southern Maharashtra with areas like Pune and subsequent interior Western Maharashtra will receive rains with rise in minimum temperature.
This shall happen on Monday,31st Dec 2012.

Pune which witnessed a min temperature around 7C shall have relatively warmer nights though a heavy rainfall event is unlikely due to the scattered precipitation tendency there..

As the moisture pumps further, it shall weaken in terms of Relative Humidity (RH) however be that much to bring cloudy skies in Nagpur and Central India.

The min temperatures will rise to around 15-17C in Nagpur taking away the winter effect in the city. Due to moisture amounts and slight unstable atmosphere, clouding shall be there in the city during ( Partial) 31st Dec and then increasing on 1st and 2nd Dec ( As of present GFS).

However, there seems to be a little problem with the initial Skew-T of that period

Above is the 1st Jan 2013 SKEW-T for Nagpur region. Its clearly visible in those indices that CAP or CIN will be greater than the CAPE ( CIN = 102 J/Kg)..
This situation depicts a non buoyant atmosphere where due to thermal inversion, buoyancy is lost thus a parcel of air ( moisture embedded) will sink as it rises due to which chance of convection and thunderstorm looks minimal now
However, the SKEW-T can change and moreover such CAP can break if there is abundant sunshine in the morning on the 1st Jan.

Situation on this rainfall event shall be more clear in the coming period

GFS shows a precipitation in Nagpur ( which then must be non convective) on 1st and 2nd Jan

Trace Amt rain can be expected on 31st Dec night ( As of 28th Dec GFS)

STAY TUNED FOR UPDATES AND FOLLOW METD WEATHER FACBOOK FOR MORE DETAILS--

First week of July to bring rains in Central India

METD WEATHER
Akshay Deoras
Severe Weather Forecaster

Finally a little good news seems to be coming in! First we shall see the last week rainfall of June 2012

Top most is the weekly rainfall ( 21st June to 27th June 2012) and the above one is the Monsoon season rainfall from 1st June to 27th June ( data updated till 29th June).

Considering the seasonal rainfall, it can be noted that only NE India ( Sikkim) i.e Assam and Meghalaya has got excess rainfall while the majority areas are in the DEFICIENT and SCANTY ZONE. The rainfall has been normal in the Western Maharashtra,Western Karnataka and some Eastern parts of Andhra Pradesh,Odisha,Chattisgarh,Lakshadweep and A&N Islands and some parts of the NE India.

The weak monsoon current and slow onset has resulted in such a large deficiency leading to multiple problems like bad sowing of the Kharif Crops,Water storage deficiency etc.

Above- The EWP map of the Madden Julian Oscillation shows the arriving wet phase ( green shade) over India. This phase is a very weak in terms of the strength but will not be so bad and hence the rainfall is expected to increase this period. 

Meanwhile, the Indian Ocean Dipole is still towards negative neutral which will be fueling the dry phase more than the wet phase as per the IndiMo 1- so again it can be expected that the rainfall will be non normal and a bit scanty from July end period. 

Favored by the MJO Wet phase and a couple of low pressures from the Bay of Bengal soon rainfall is expected in a wide area of Central India 

On 1st July, 

Areas like Washim,Akola and vicinity will be receiving some rainfall. The rainfall is expected to be convective or thunder rains in nature. Some more parts of Central,Eastern Maharashtra also will receive rains. 

2nd July-

The rainfall is expected in the entire Maharashtra state including Nagpur,some parts of Madhya Pradesh ,Chattisgarh as well. This rainfall can be expected to be little good in terms of the sowing of the Kharif Crops in these areas ( if sowing has not been done) 

3rd July- 

The rainfall is again expected in the above areas and will be considerably good helping the seeds. The rainfall is expected in a region from Central MP,Chattisgarh,Maharashtra prominently 

4th July-

The rainfall is expected to decrease a bit in Maharashtra but will be the same almost in Chattisgarh. Isolated rainfall can be expected in many parts of Maharashtra due to the low effect. 

5th July-

Rainfall expected in Central,Northern Madhya Pradesh,Chattisgarh and areas around Chattsgarh 

SYNOPSIS-

* GOOD RAINFALL IS EXPECTED AROUND/IN NAGPUR,VIDARBHA AND SURROUNDING DISTRICTS IN MAHARASHTRA,MADHYA PRADESH FROM JULY 2 ONWARDS

* THE RAINFALL SEEMS TO BE SUFFICIENT ENOUGH ( BETTER THAN THE PREVIOUS) FOR THE SOWING OF KHARIF CROPS IN MAHARASHTRA ESPECIALLY CENTRAL INDIA

* SUCH AN EVENT OF BETTER RAINFALL MAY NOT BE POSSIBLE AGAIN TILL SOME DAYS IN JULY

* FARMERS WAITING FOR THE RAINFALL IN CENTRAL INDIA SHALL THINK OF SOWING ON 2ND JUNE OR 3RD JUNE 

Will SW Monsoon reach Central India on time?

METD WEATHER
AKSHAY DEORAS
SEVERE WEATHER FORECASTER

In the IndiMO II, METD WEATHER had issued 19th June 2012 as the monsoon onset date for Nagpur and a general of 14th-19th June 2012 for the Central India. The monsoon however as mentioned in the previous posts is very slow and almost stalled which is making this decision difficult

METD WEATHER CONDITIONS for Monsoon onset--

1] MONSOON

A) - HEAVY RAINS

THE MONSOON RAINFALL OR THE ONSET OF MONSOON IS CONSIDERED ON THAT DAY WHEN THERE ARE HEAVY RAINS ( *** NOT APPLICABLE FOR RAINFALL DUE TO ANY CYCLONE LANDFALL***). 

RAINFALL ACCUMULATION MUST BE MORE THAN 5mm

*** CONVECTIVE RAIN AFTER SUNNY MORNING SHALL NOT BE CONSIDERED AS MONSOON RAINS***

B)- WINDS

THE WINDS ( SURFACE-500MB) MUST BE FROM SOUTH-WEST ATLEAST FOR 48HRS AND HAVING INTENSITY OF MORE THAN 10KT IN ALL LEVEL. 

( WINDS FROM SOUTHWEST FOR A DAY ARE NOT TO BE CONSIDERED AS MONSOON WINDS) 

C) MOISTURE

***SURFACE RELATIVE HUMIDITY MUST BE GREATER THAN 60% ATLEAST FOR 48HRS 

*** THERE MUST BE A DEEP LAYER MOISTURE IN ATMOSPHERE IN LAYERS 500MB-900MB ATLEAST FOR 48HRS WITH SATURATION ***

D) AIR PRESSURE

*** SURFACE AIR PRESSURE IN A REGION ( NOT APPLICABLE FOR HILLY REGION) SHALL BE BELOW 1006 MB CONSECUTIVELY FOR 2-3 DAYS. SINCE LESS PRESSURE REGION INDICATES LOCALITY OF THE MONSOON TROUGH. 

*** ANY PERIOD WHEN SURFACE AIR PRESSURE GOES ABOVE THE LIMIT SHALL NOT BE CONSIDERED FOR MONSOON ONSET*** 

E) TEMPERATURE

*** SURFACE AIR TEMPERATURE MUST DROP TO 35C OR BELOW AFTER PRECIPITATION

*** TEMPERATURE SHALL BE MAINTAINED IN THE MAXIMUM LIMIT AS 35C ( MAX TEMP) ATLEAST FOR 48-72HRS. 

*** TEMPERATURE ABOVE THE LIMIT SHALL NOT BE CONSIDERED FOR MONSOON ONSET***

F) CLOUDING

*** DUE TO DEEP LAYER MOISTURE,CLOUDING SHALL BE PRESENT IN THE REGION 

*** OVERCAST CONDITION ATLEAST FOR 24HRS CONTINUOUSLY

ANY CLEAR WEATHER DAY WITH ALL THE ABOVE CONDITION POSITIVE ( EXCLUDING RAINFALL) SHALL NOT BE CONSIDERED FOR MONSOON ONSET

G) 850MB MOISTURE TRACK FOR NORTHERN LIMITS OF MONSOON

THE NORTHERN LIMITS OF MONSOON SHALL BE ADVANCED ONLY WHEN 850MB MAP SHOWS MOISTURE OF RELATIVE HUMIDITY GREATER THAN 60% AND BEING MAINTAINED FOR 2-3 DAYS

THE ABOVE ARE THE CONDITIONS WHICH METD WEATHER HAS BEEN CONSIDERING SINCE LAST 3 YEARS AND REGARD AS THE CORRECT MEASURES TO DETERMINE MONSOON ONSET. 

THE INDIAN METEOROLOGICAL DEPT NORMS ARE DIFFERENT AND HAVE NO CONNECTION TO THE DATES FORECASTED BY METD WEATHER 

Present conditions in Central India-

1) Rains ( IMD Nagpur)

As can be seen from the rainfall on 16th June evening till 1000hrs of 17th June, Jabalpur in M.P has got the heaviest rainfall of 75.7mm followed by Chadrapur in Maharashtra of 44mm and Nagpur getting 11.8mm rainfall. 

Still heavy rains weren't reported for more than half of the stations above. 

2) Winds-

The peak winds in Nagpur since 16th June were around 20km/hr mostly from West. The upper air winds also are satisfying the conditions. 

3) Moisture- 

The Surface Relative Humidity (lowest) was 35% at Nagpur at 0530PM on 16th June. This definitely doesn't fit into the criteria of the monsoon onset.

4) Air Pressure at the surface

The mean air pressure was around 1002mb since 16th May. The pressure is being maintained since 24hrs. 

5) Clouding- 

The overall cloud cover falls in the Mostly Cloudy with today being the same in Nagpur. 

6) SFC temperature

The surface air temp of Nagpur on 16th June was around 38.2C which violates the norms

The 850mb shows some moisture in the region. 

If these conditions ( except temp,moisture) are favorable then why isn't METD WEATHER declaring the onset???

Here is the latest (00z,17th June) GFS Nagpur Meteogram. The topmost profile shows the atmospheric moisture till 25th June. As can be seen that the amount of moisture in the region is strongly decreasing from around 18th-19th June. The 2m RH plot also shows a strong decrease in the moisture amounts with absolutely no rainfall expected from 20th June onwards. 

If METD WEATHER declares the onset of Monsoon in the region then the immediate dry phase will take over with no rains. The parameters also aren't expected to remain consistent as a result the change of monsoon onset on 19th June is very low...... 

Abhijit Modak from Badlapur city,Maharashtra sends these photos taken today (17th June 2012). Badlapur is an Extended Central Line Suburb of Mumbai in Thane District.  . These photos clearly show the heavy rains in the region.  

Strong Thunderstorms,Heavy Rains possible in Central India on Thu-Fri

REFERENCE MAP TO DESCRIBE THREAT LEVEL AS MENTIONED BELOW

METD WEATHER

Akshay Deoras

Severe Weather Forecaster

A round of severe weather can be expected in the Central India region from Thu-Fri ( 21 and 22nd Apr 2011)

For Thursday,21st Apr 2011

Severe storms are expected to fire at the nose of the southern extent of jet stream aloft as the surface low continues to intensify in the region with the MSLP as per Thai Meteorological Dept of 1002mb! As the surface low deepens, it shall pull moisture from the Southern Region and South Western Region along with the Low Level Jets of 24-32kt thus providing the moisture in the persistent unstable atmosphere

The GFS 12z runs indicates upto 1000J/Kg CAPE present over Central India while the same timed Skew T indicate upto 500J/Kg joules in AN UNCAPPED ENVIRONMENT

With enough instability to support convection, and INSANE LIFTING ( LIFTED INDEX UPTO -5!!), Severe thunderstorms capable of producing Heavy Rains,Lightning,Strong Winds,Sudden drop of temperature shall be very likely

The main concern is for the following areas

Nagpur and the 100km circle radius as shown on Doppler Images

Areas around Gondia where strong CAPE is present

Isolated areas NE of Seoni in Madhya Pradesh

West of Amravati

** All areas in 200km radius of Nagpur as the center

Threat-

Threat is for Rains,Strong Winds,Hails and strong lightning during late evening into night

---------------------------------------------------------------------------------------------------------------------

For Friday- 22nd Apr 2011

As more moisture is dumped on Friday, with comparitively less instability

threat shall continue for Heavy Rains

These areas include -

Nagpur,Central and Southern Madhya Pradesh and other areas 200km radius of Nagpur ( Excluding the areas beyond 50km west of Nagpur)

** Flash Flooding also possible in areas like Southern MP,Vidarbha many areas in the 100km circle of Nagpur

Preparation -

Keep yourselves dry using raincoats and umbrellas all the time.

Stick to METD WEATHER forecasts @ facebook.com/deorasakshay

Don't stand under tree during lightning

METD WEATHER ALERT_

Areas in the 150km zone from Nagpur as center are specially alerted for chance of strong thunderstorm on Thursday followed by rains on Friday

MARK 5 ALERT in effect till 0600hrs,Sat

Additional rainfall also shall hit Chattisgarh,Western Orissa during this period

METD WEATHER BLOG COMPLETES 17000 PAGE VIEWS FROM MAY 2010 TILL NOW

Strongest Storms possible in Central India on Saturday

METD WEATHER

Akshay Deoras

Severe Weather Forecaster

Concerning- High Risk of Severe Storms across Vidarbha on Saturday ( 16th Apr 2011)

Persisting High-Low pressure collaboration of air pressure in Arabian Sea and Mainland of Central India is already pushing April to ITS LIMITS !

With a Hailstorm on 9th Apr 2011, Strong Thunderstorm today in Nagpur ( METD WEATHER captures around 7 lightning bolts with tremendous lightning flash so powerful to make the night appear as day! )

( Video available by Monday)

Forecast-

Severe weather event is expected to unfurl with some of the best conditions together at place I have ever seen in my life for India!

The moist parcel of air shall be lifted robustly with steep lapse rate by afternoon when convection temperature reaches in Vidarbha area. The Lifted Index ( LI) are over -3 indicating presence of a Robust Lift having over 338K Potential Energy release ( Theta E)

Due to synoptic lifting of parcel of air and presence of moist air for saturation, Convection shall be assisted by presence of a Strong Day time lifting adding to the CAPE of over 432J on surface and equivalent in Unstable layers.

The 12z,GFS guidance confirms that lower layers of atmosphere shall be unstable with the Cloud Condensation Level ( CCL) at around 720mb ( 9000FT) where as the forecasted Equilibrium Level is around 35,000 ft ( Cloud Tops) in Uncapped environment.

K= 37

TT= 48

PW ( cm) = 3.13

This means that the towering CB shall have rapid intensification shortly after convection fires in the afternoon period

** THE STORMS SHALL QUICKLY MODIFY INTO DANGEROUS CB CAPABLE OF PRODUCING HAILS, RAINFALL AND STRONG WINDS

** SPECIAL THREAT FOR CLOUD TO CLOUD OR CLOUD- GROUND LIGHTNING

WITH RAPID LIGHTNING INTERVAL **

** To which area there is threat?

The primary concern seems to be areas in 100 km circle from Nagpur where there are best convective potentials.

** Areas around Chandrapur

Threat is limited to areas around Amravati, Chinwada and all

** How to prepare for it?

The best way to face Saturday setup is by keeping a raincoat/umbrella throughout the day. Though it w'd be CLEAR and warm in morning- afternoon, after convection happens weather w'd change drastically.

Also, as soon as an alert is issued on facebook.com/deorasakshay or you see a lightning bolt, switch off and unplug electric devices