DUST STORM DEEPENS IN INDIA,SPREADS IN CENTRAL INDIA ALSO

METD WEATHER
AKSHAY DEORAS
SEVERE WEATHER FORECASTER



CHECK THE LATEST ON THE BLOG!!


MAJOR SITUATION UNFURLING! 
*** DUST REACHES CENTRAL INDIA,GRIPS MUMBAI ALSO*****

SHAN FASTIAN SENDS THIS WONDERFUL PHOTO FROM ISLAMABAD,PAKISTAN . THE PHOTO WAS TAKEN AT 04PM LT,20TH MARCH 2012. 

WIDESPREAD DUST REPORTED IN BHOPAL,MADHYA PRADESH**************


THE SUPER DUST STORM OF THE MIDDLE EAST WHICH GRIPPED SINDH,GUJARAT,RAJASTHAN AND SOME PARTS OF NORTH INDIA STRETCHING AS FAR AS SRINAGAR HAS REACHED CENTRAL INDIA TODAY AS THE DRAMATIC DUST PLUME CHANGED ITS PATH. 


WIDESPREAD DUST HAS BEEN REPORTED SINCE EARLY MORNING TODAY IN MADHYA PRADESH WHICH IS BEING CONFIRMED BY THE VISIBLE SATELLITE IMAGERY AND THE COLOUR COMPOSITE SPECTRUM ALSO







AS SEEN FROM THE ABOVE COLOR COMPOSITE SATELLITE IMAGERY, THE MAJOR DUST PLUME WHICH CAN BE NOTED IN THE CENTRAL ARABIAN SEA ORIGINATING FROM LOWER SAUDI ARABIA HAS GRIPPED CENTRAL INDIA,WESTERN INDIA AND NORTHERN INDIA ALSO..


REPORTS AND FORECASTS-

As was expected, the conditions are IMPROVING FURTHER FOR MIDDLE EAST I.E GULF COUNTRIES,OMAN. THE PAST 7-8 HOURS OF DATA SHOWS IMPROVING VISIBILITY AND LESS REPORTS OF WIDESPREAD DUST~ HOWEVER AS WAS EXPECTED, THERE ARE STILL SOME SUSPENDED DUST PARTICLES IN THE AIR FAR LESS THAN WHAT WAS ON 19TH AND 20TH MARCH

CONDITIONS ARE ALSO IMPROVING IN RIYADH AND OTHER SAUDI ARABIA REGION.

SINDH-
THE INTENSITY OF DUST HAS REDUCED IN SINDH REGION AND OTHER PARTS OF PAKISTAN. HOWEVER THE DATAS ARRIVING STILL INDICATE A MODERATE TO MINOR DUST PRESENT WITH REPORTS OF BLOWING SAND ALSO

INDIA-


THE DUST HAS GRIPPED SEVERELY IN GUJARAT,RAJASTHAN AREAS. THE SATELLITE IMAGERY CLEARLY SHOWS THE LARGE PLUME OVER THESE AREAS


THE DUST PLUME HAS ALSO MIGRATED TOWARDS MADHYA PRADESH REACHING BHOPAL


AS OF 0430GMT, THE SOUTHERN LIMIT OF DUST PLUME IS FEW KILOMETERS SOUTH-WEST OF BHOPAL CITY AND IS PROGRESSING SOUTH. 


FORECAST- 

Right now, 
A cold front is being driven across Saudi Arabia which is confirmed from the cloud pattern. The Cold Front is expected to advance further south-east. A Widespread dust is still present over Saudi Arabia. If this cold front happens to advance further, it will kick off the dust in the Arabian Sea which may result into the upsurge in the amount of dust over Arabian Sea. 


In India, a system of two low pressures is pulling the wind and subsequently the dust plume. One low pressure is offshore Goa-Karnataka border while the other one is somewhere over the North-East part of Central India which has caused the perpendicular shape of the plume and advancement of the plume in Central India


***MIDDLE EAST,OMAN 
CONDITIONS WILL BE IMPROVING FURTHER WITH SOME SUSPENDED DUST PARTICLES TODAY. 


*** IN MUMBAI WHERE THE DUST IS STILL BEING REPORTED CONDITIONS WILL WORSEN IN THE AFTERNOON PERIOD AS THE ADJACENT PLUME MAKES ITS ENTRY. 
SOME OBSCURING VIEWS ARE VERY LIKELY WITH MINOR DIP IN THE VISIBILITY THIS NOON 


*** THE SYSTEM OF LOW PRESSURE WILL ADVANCE THE DUST FURTHER SOUTHWARDS AND THE DUST WILL BE ENTERING MAHARASHTRA THIS AFTERNOON TO EVENING PERIOD. 


VOLUME WILL BE LESS BUT AREAS LIKE NAGPUR AND VICINITY SHALL GET TO SEE A TRAILOR OF THE EVENT WITH OBSCURED VIEWS OF THE AIR,ATMOSPHERE


*** FOR SINDH, CONDITIONS WILL FURTHER IMPROVE TODAY. HOWEVER SUSPENDED DUST PARTICLES WILL BE THERE IN ATMOSPHERE ATLEAST TODAY


INDIA- 


*** THE CONDITIONS ARE EXPECTED TO WORSEN FOR CENTRAL INDIA PARTICULARLY IF THE LOW PRESSURES MAINTAIN THEIR STRENGTH. IT MAY RESULT IN PULLING OF THE DUST FROM WESTERN PARTS TO CENTRAL PARTS


THE CONDITIONS IN GUJARAT AND RAJASTHAN ARE EXPECTED TO IMPROVE SLIGHTLY WITH SOME VISIBILITY IMPROVEMENTS. HOWEVER SUSPENDED DUST PARTICLES WILL BE THERE CAUSING ANOTHER DAY COVERED WITH DUST


*** NAGPUR-


THE CITY MAY ENCOUNTER THE DUST TODAY EVENING. 


********** IF THE DUST OVER CENTRAL INDIA WEAKENS THEN NAGPUR WILL NOT RECEIVE THE DUST AND CONDITIONS WILL IMPROVE**************


SHORTLY UPDATING ON IT




STAY TUNED FOR UPDATES-

Conditions improving after the Dust-Storm in Gulf Countries

Img courtesy-
Asad Ali from Karachi,Pakistan

AKSHAY DEORAS
SEVERE WEATHER FORECASTER

CONDITIONS IMPROVING IN SINDH REGION,OMAN AND GULF COUNTRIES AFTER THE DUST STORM


The Major Dust Storm which hit the Gulf Countries and particularly Oman and Sindh regions is now subsiding. The conditions like visibility and pollutant air is improving rapidly in the areas as the datas are informing and METD WEATHER fans are reporting from these areas!

Visit-
facebook.com/deorasakshay to participate in the latest discussions!

The latest-
A Moderate Dust-Storm is now affecting Pakistan. Reports coming from Pakistan especially Karachi indicate "Widespread dust"," Blowing Sand". Asad Ali from Karachi has sent the photo which you can see at the top. The photo is of evening period on 19th March 2012.

IT happens because of the jet streams. The jet streams after entering in the Arabian Sea move north-eastward towards India from regions over India-Pakistan border particularly Gujarat state.

IT can be seen in this Jet Stream map



Analysis of the present amounts of Dust-

Above- Satellite imagery showing widespread dust over Pakistan!
Courtesy- MODIS

The above imagery clearly shows the dust plume lying in the North Arabian Sea. As seen from the image, there exsists a High pressure system somewhere over Iraq and a low pressure prevailing over the Arabian Sea has boosted the Shamal winds. A powerful jet and mid atmospheric winds have started bringing the dust towards India also.

RingRoad Weather Station's Weather Forecaster,Ashokbhai Patel reported today morning about the Hazy conditions in Gujarat. This news is a confirmed one as the Ahmedabad's weather station parameters confirm it.

Right now, conditions are much relaxed in the Gulf countries,Oman. However the satellite imagery shows some dust spread over Saudi Arabia southern end ( marked in red circle as DUST PLUMES)
The persisting winds shall be sending the dust more towards Sindh area and India especially Gujarat area.

I don't forsee any other parameter which can trigger another sandstorm in Gulf countries and Oman today

FORECAST-


WIDESPREAD DUST,BLOWING SAND WILL CONTINUE IN PAKISTAN,GUJARAT FOR THE NEXT 24 HRS ATLEAST.
* WIDESPREAD VISIBILITY PROBLEMS POSSIBLE IN THESE REGIONS***


*** DRIVERS ARE REQUESTED TO MONITOR THE CONDITIONS CAREFULLY***


THE OTHER STATES OF INDIA WILL NOT BE AFFECTED. HOWEVER SOME DUST MAY REACH PARTS OF NORTH INDIA

Into the Shamal Duststorm of Gulf countries which has engulfed the areas!

METD WEATHER
Akshay Deoras
Severe Weather Forecaster

MAJOR DUST-STORM HITS SAUDI CITIES,KUWAIT CITY,OMAN AND OTHER GULF COUNTRIES




Though the Dust-Storms are common in the Gulf States, a major dust-storm hit parts of Saudi Arabia,Kuwait,Oman,Gulf Countries like UAE and Yemen. Flight delays have been reported in Yemen.
Poor visibility conditions are being reported from UAE,Oman. In Sindh area also poor visibility and widespread dust is being reported.

Below are the photos of today afternoon from Muscat sent by METD WEATHER's Fan Mon Soon.
One can clearly see the dust in the two images.

More photos from UAE can be seen here-

The necessary conditions (discussed below) came together which triggered a dust storm. The passage of cold front across Saudi Arabia, Oman has caused the temperatures to come down significantly.

The 1430z satellite imagery clearly shows dust feature in Saudi Arabia and South-West of it. Flaring convection is seen at the lower left of the image indicating some presence of a low pressure area

WARNING AND FORECAST:


* THE TYPICAL PERIOD OF A SHAMAL SANDSTORM IS 3-5 DAYS. * HOWEVER CONDITIONS ARE NOW DECREASING FOR ANOTHER MAJOR ONE 
*HOWEVER PEOPLE ARE REQUESTED TO FOLLOW THE LOCAL WEATHER AND GOVERNMENT OFFICIALS. 
*THE ROYAL OMAN POLICE HAS WARNED PEOPLE OF OMAN TO TAKE PRECAUTIONS TILL THIS WEDNESDAY


What are such dust-storms???

Dust-storms often referred as Sandstorms are a natural phenomena occurring in the arid,desert regions where there are persisting conditions for synoptic lifting of sand i.e having a significant source of sand in the vicinity. The primary condition required for a sandstorm is the presence of a large area of sand. An image posted below shows the Dust source areas which are widely observed in Iraq.

Below shows the Major Dust producing Regions where there is a significant region in Iraq,Saudi Arabia

Courtesy- Air Force Weather Agency/NRL,USGC and COMET education programe.

The Next prominent thing required depends on the type of the dust-storm. There are two types
1) The Haboob
2) Shamal type

We shall not consider much details about the Haboob type as the recent sand-storm is of the Shamal Type.In the Haboob type, the outflow of a thunderstorm is responsible for triggering the sand-storm.
The thunderstorms have an outflow boundary and hence an ouflow where the winds are moving out of the system as the thunderstorms move. The gust front or the leading edge of air of a thunderstorm then carries dust with it. In a similar way, downbursts also trigger the storms. Downburst happens when the downdraft (coloumn of air coming down from thunderstorm) appears suddenly.

Example of Haboob-

The another type is Shamal type of a dust storm!

In a Shamal type, the dust storm is created due to a perfect combination of air pressures and air fronts.
In a Shamal type, an airfront (mostly cold front) where a cold front is a leading edge of a cool air mass carries dust with it.

What is a Shamal??
Its a local name given to the North-Westerly winds blowing at lower levels of the atmosphere over areas like Iraq,Saudi Arabia,Kuwait etc. As a North-Westerly wind setup is responsible for this type of dust-storm, its named as Shamal dust storm.

Mechanism-

We shall now see how a Shamal type of dust storm or pre-frontal dust storm is set up!
The most important ingredient required is a Low Pressure area over Iran or vicinity. Low pressure area forms when the air in the region rises up in the atmosphere reducing the overall air density and hence pressure in the region. Occasional low pressures form in the areas like Iran at the 500mb or mid atmosphere level.
As seen from the below map, the areas north of Syria etc have higher elevation. When the Shamal winds blow, they carry cool air from that region towards warmer region or warmer air of areas like Saudi Arabia etc. Thus the leading edge of this air mass is what we call as the cold front denoted by the black line with triangles over Oman region . Since the below region shows the Shamal sandstorm at an age of 3-4 days i.e 3-4 days after its birth.

In the below image, just below L 500mb in Iran you can see white dashed lines. The white dashed lines are called as troughs which are nothing but imaginary lines which can be drawn which connects low pressure regions. This trough feature is easily noted in the upper level maps





Above-  IMG 2
The upper atmospheric map shows the trough feature over Iran. Its an amplified trough (shown by a bit purple region)

Image Courtesy-

THE COMET PROGRAME

 

There is also a jet stream factor (jetstreams are the currents of air at higher altitude of over 30,000 ft which are flowing throughout the world from west to east direction ). Whenever a polar jet stream digs more southward near Iraq or Syria area it comes much closer to the subtropical jet stream which presence is shown in the upper atmospheric map i.e IMG 2. Due to this, there is a interaction between the two jets which amplify a part of the cold front as seen below



In the above image, the blue line is a cold front heading in the direction where the triangle is pointing, it can be seen that the surface max winds are amplified and hence much more sand can be lifted in such a case. Also due to this arrangement lifting of sand is enhanced.

Thus all the conditions are together for a perfect shamal sandstorm.

Associated dust area-

Depending on the cold front movement, the dust area is divided into two parts-
Pre-frontal area and post frontal area.
A pre-frontal area is that area from where the cold front is yet to pass and post frontal is that area over which the cold front has already passed.


Here,
the red lines are warm front which is opposite to the blue cold front!


What to do during a dust-storm

Check this link
http://www.wikihow.com/Survive-a-Dust-Storm-or-Sandstorm