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Saturday, December 31, 2011

Wintry & Colder Feel To The Start Of The New Year 2012

1st January 2012

Wintry & colder feel to the start of the new year

The start of 2012 will see some wintry showers falling as snow across parts of northern Scotland during new years day. This wintry theme will continue as we head into Monday, with further wintry showers across Scotland, Northern Ireland, and northwestern parts of the UK. Some of these wintry showers will also fall as snow across higher and lower ground in these parts, leading to some accumulations of snow in places. There may even be the risk of some snow showers across higher ground in some areas further south. Tuesday will see yet another area of low pressure arrive, bringing with it some strong winds and wet weather across many parts of the UK. Some of these showers will initially remain wintry across Scotland and some northern regions of the UK during Tuesday, before a brief return to milder conditions across many parts of the UK.

I stated on the 2nd September 2011 that we could expect:

a notable increase in usual wind strengths for this time of year across many parts of the UK, that will result in frequent and potentially damaging gale force winds and strong stormy features throughout autumn and WINTER.”

I also stated in my last update on the 25th December 2011 that:

January certainly looks promising for this at present, in terms of some true cold and snow across Scotland and northern regions of the UK. Although once again there is likely to be some periods of moderation at times, and this is most likely to be reflected in any areas further south.”

February should prevail further in comparison to January, and this is when I feel we are likely to see the most severe part of this winter. A cold start to spring 2012 is also possible, with some especially heavy and widespread snowfalls across Britain and parts of Ireland.”

This is currently still how I see things developing throughout January and into February at present. Although the worst of the strong winds, cold, and snow for January, is more likely to occur from around mid-month onwards. There will also be some interspersions of milder weather at times throughout January, and areas further South are the most likely to see the best of these conditions. I am currently expecting the mean Central England Temperature (CET) to come in at near or below-average for January. Any further updates will be posted accordingly.

May I finally take this opportunity to wish you all a Happy New Year for 2012!


The winners of the white Christmas 2011 competition will be chosen at random and posted on the Exacta Weather homepage later today.

James Madden (UK Long Range Forecaster)

ExactaWeather.com

Published: 1st January 2012 (06:03) GMT
Content copyright © 2010-2011. Exacta Weather. All rights reserved.

Happy New Year to the Central US!

Happy New Year to those in the East US!

Potentially Major Winter Storm Shown on ECMWF

Hour 192 of 12z ECMWF
Here, we see two low pressure systems- a cutoff low in the Southwest as well as another system moving onshore Canada. As of right now, they appear to be 2 separate storm systems.
Hour 216 of 12z ECMWF
At hour 216, we are seeing the same two low pressure systems moving eastward. It looks like the cutoff low may be getting some energy from the Gulf, and I could see a snowstorm hitting Missouri and states to the west of Missouri. The other disturbance in Canada continues to move east.
Hour 240 of 12z ECMWF
At hour 240, we are seeing some major phasing occur in the Western Great Lakes, which may indicate a major winter storm could hit the far Northern Midwest areas into Canada.

12z ECMWF Strengthens Polar Vortex-Disrupting Ridge; GFS Introduces Deep Trough Pattern to Great Lakes

Both the ECMWF and GFS are portraying at least some sort of disruption in the polar vortex, as well as at least a slight indication of a cutoff low pattern in the Southwest judging by the 500mb height isobars. However, each model has a different scenario.
The ECMWF brings in a very strong ridge into the polar vortex. If this were to stay in place, essentially the polar vortex would break down, and all of the bitterly cold air would come rushing south, as the lack of motion by the deep low pressure systems would eventually take its toll. This would certainly be a very interesting development. But because not all models do good in the long range, we will have to take this as a 'heads up' item, rather than a sure fire assurance. Additionally, the ECMWF places a ridge in the Northeast.
The GFS introduces a lesser ridge into the polar vortex, but it's still enough to cause problems. A much bigger interest is how the GFS is showing a deep trough pattern in the Great Lakes, which appears to be stemming off of the low pressure systems in the polar vortex itself. It also shows a weak cutoff signal in the Southwest, judging by the isobars.
All in all, this will definitely be something to watch. I would get your snow removal equipment ready, because this is something i'm having a feeling may cause a snowstorm somewhere in the US.

New Years Day Forecast - Valid 1/1/12

New Year's Day 2012 is already upon us, and that means it's time for your New Year's Day Forecast!
PROBABILITY OF PRECIPITATION
POPcast from intellicast.com
Valid 7:00 am EST
Throughout the Day, we will be seeing some precipitation throughout the upper Midwest and Great Lakes as a system will be moving eastward from Canada. It will be a strong system, so plowable snow is likely. We have snow accumulations below.
POPcast from intellicast.com
Valid 7:00 pm EST
In the evening hours, there will still be potential for some precipitation in the Great Lakes area, where strong winds will bring in harshly cold air to start the new year.

SNOW ACCUMULATIONS
48 hour snowfall from intellicast.com

48 hour snowfall from intellicast.com
There is potential for upwards of 8 inches in Michigan from this lake effect snow, with some 1-4 inches of snow across Minnesota and Wisconsin from the system itself, and some lake effect snow closer to the Lakes. By far, Michigan's both upper and lower sections will be the hardest hit. Accumulations may look light on the Eastern side of the Lakes, but that may be because the lake effect machine is only starting to kick in at the 48 hour mark.

WIND SPEEDS

WINDcast from intellicast.com
Winds will be very strong on New Year's day, with sustained winds over 30 MPH on land, and over 45 MPH on Lake Michigan.
Here's a meteogram based in Chicago IL, one of the harder hit areas we are expecting of the winds. You can use the dashed lines that say (i.e. 06z GFS Max MT) for wind gusts, because 'Max MT' is essentially meaning the maximum wind gust that may happen in the area, in this case Chicago. (Mean MT is the mean wind gust expected.)
Click to enlarge
The 6z GFS Max MT is up at 70 MPH! Now keep in mind that the Max MT is the ultimate maximum for wind speeds and probably will not happen. A more reliable wind gust measurement would be the mean MT.

Have a great New Years!

Friday, December 30, 2011

ECMWF/GFS Showing Polar Vortex Breaks, Cutoff Low Pattern to Return in Southwest

Both the 12z ECMWF and 12z GFS are showing a break in the polar vortex- a significant development that may lead to the much-anticipated pattern change. Another thing we're seeing in these 8-10 day height anomaly outlooks are trough patterns in the Southwest as well as offshore the Southeast. This means that the cutoff low pattern may return to the Southwest and bring some snowy weather to the Plains. Possibly. A lot has to be determined, but it does match up with my theory of cutoff lows returning.

January 3-5 Lake Effect Snow (Great Lakes Affected)

Hour 90 of 12z GFS
As the system that will be bringing harshly cold air into the US departs, this cold air will work quickly to ignite the lake effect snow system for the Great Lakes. This lake effect snow, while it may not stick, the snow may be enough to coat the ground. Here's the forecast snow depth from the 18z GFS.
The snowfall from the lake effect snow may put down up to a foot of snow up in the far northern reaches of Michigan. Lake Michigan may put down up to 6 inches of snow, with lesser accumulation in the eastern Great Lakes.

January 2-4 Snow Event (Midwest, Great Lakes Affected)

Hour 42 of 12z GFS

Hour 48 of 12z GFS
The 12z GFS is showing the strong system expected to cross Canada also drop down some precipitation in the Upper Midwest and Great Lakes. Seeing as how it appears that a cold front of sorts will be bringing in cold air behind this wave of precipitation, I can see snow accumulations in the Upper Midwest.
There are two sides to this storm: precipitation and temperatures. Here's 850mb temperatures from the ECMWF.
Hour 48 of ECMWF

Hour 72 of ECMWF

Hour 96 of ECMWF
As this system moves through, we will be seeing the coldest air of the season move through the Midwest, and even down to Florida before curving back up to the Northeast. The coldest air should flow through the Midwest and Northeast as this major cold wave moves through. The ECMWF is showing 850mb temperatures below 0 degrees down through Florida. By far, this will be the biggest cold wave the nation has experienced. If the wave of storm systems continues to come through Canada in the same fashion this one did (as is expected), we will continue to see big cold blasts as well as likely displacing some of the polar vortex.

Icy Mix Possible This Evening in the Northeast

PrecipCAST from intellicast.com
Time valid for 10:00 PM EST
As a clipper system moves east-northeast into Canada, we will be seeing a mix of precipitation in northern parts of New York, as well as north Vermont. This could make for some slippery conditions on roads for that area. Some snow may mix in, depending on the temperature gradient for the area as a from precedes the system itself. Rain and embedded thunderstorms will be occurring right near the storm system itself out by Michigan. However, it isn't looking like any huge thunderstorms will be present. There is a freezing rain advisory for a small portion of northern New York depicted below:
Map is not interactive

Full Winter Update, Snowstorm Predictions, Long Range Predictions

We are seeing a major stratospheric warming event take place in the last several days. We are seeing some big temperature anomalies from the 30mb level up to the 1mb level. The big part is that the warming is occurring over Alaska. Because the warming is occurring over Alaska, we might be seeing the semi-permanent low pressure system over Alaska weaken as the warming may progress down into the troposphere. If this warming continues, the pattern change would definitely be helped along. The warmth may be able to propagate into the North Pole, where a disruption in the Polar Vortex could break the stubborn +AO/+NAO regime which has been producing a snow drought over the East US.
Here we have the 0z ECMWF 500mb analysis over the far North Hemisphere. We see the strong low pressure systems right over the North Pole. We can see the strong low pressure system over Alaska, where we are seeing warming occurring. Now let's skip ahead to hour 168.
At hour 168, we are seeing a ridge from Asia pump north into the polar vortex and interrupt it for a little bit. This ridge will be pulled north into the main polar vortex and disrupt the vortex. Essentially, the NAO and AO will also be disrupted. The AO, which is based in the North Pole, is the biggest piece that will be affected. If the vortex breaks, the extremely cold air that has been locked up may flow southward as the vortex breaks. Moving ahead to hour 240 is seeing the low pressure system over Alaska take a big weakening hit, which may bring some active weather into the US. However, no model does well at 10 days out, so take this as something to watch.
But let's say that this disruption does happen. Well, what would happen to the all-important NAO?
OLD 0z ECMWF
The old 0z ECMWF shows the point of when the expected break in the polar vortex is, as well as the effects of the polar vortex break. The new 12z ECMWF does now show the downward trend, but an up-and-down pattern similar to what we have outlined as the time when the vortex breaks. We are still seeing a more persistent ridge break into the polar vortex, however, so the NAO image above should not be discounted.

The NAO has been wildly swinging. With stronger systems bringing stronger positive NAO values, this means the potential for lower NAO values, going off of Newton's laws: With every action there is an equal and opposite reaction. If we use that law, it can be determined that a strong +NAO value will eventually lead into a strong -NAO sometime this winter.

SNOWSTORM PREDICTIONS---
Pre note: Confidence is low on these predictions. It is entirely possible that these snowstorms will not happen. In other words, don't hold me to these.

January 6-11: An active period is already setting up that should lead into the first couple weeks of January, if not longer. Among those possibly affected include the North Plains and the Northeast.

January 14-18: A couple shots of low pressure systems into the Southwest could make for a good snow somewhere in the Plains or Midwest.

LONG RANGE PREDICTIONS---
A quick start to January will continue as the deep low pressure system over Alaska weakens as the ridge interrupts the polar vortex in the early new year. Late January may bring a deep chill to much of the country as the Arctic Oscillation dips far enough into negative territory to unleash pure Arctic air. Using Newton's Laws mentioned above, we can expect a BIG snowstorm for the Northeast sometime this winter when the NAO goes negative in response to a very positive NAO so far this winter.

Pattern Change Update at 3:00 PM CST


Tropical Storm Thane sends moisture towards Central India. Rainfall likely in some areas

METD WEATHER
Akshay Deoras
Severe Weather Forecaster

The former tropical cyclone Thane which made a landfall South of Cuddalore at around 0500hrs IST today with a pressure of 985mb created moisture band North of LLCC during its final journey. 

As seen from the above GFS 850mb map, the past cyclone Thane is the anti clockwise whirl at South India while to its North the moisture from Bay of Bengal which was influenced by the system is digging in Central India. 
A High Pressure region  at the Mid levels will be intensifying at North of Bay of Bengal just over West Bengal. This High pressure region will channelize the moisture to spread over Central India with the earlier Northerly winds turning Southernly from tomorrow onwards



As seen from this 72hr i.e of 1st Jan 2012 plot, a much of rainfall is being seen over East Central India especially around Nagpur. 
The rainfall shall be eminent in Madhya Pradesh,Northern Maharashtra on 31st Dec 2011,spreading over a large area on the first fay of New Year!

As a result of the favored moisture and destabilized atmosphere, Rainfall shall be expected in Nagpur on Saturday night period with Mostly Cloudy weather. There will be an upsurge in the min temp to 20C ( +8C) due to this. 

If the GFS is to be believed, the lifting mechanism shall be good on Sunday where some isolated thunderstorm is expected with some rainfall in the city!

Forecast for Nagpur- 

30/12- Mostly Cloudy with convection building
Min temp to be around 19C

31/12- Day shall begin with clear or light clouds but with the reach of convection temperature in afternoon,CB clouds will build and an isolated thunderstorm can be expected in or in the vicinity of Nagpur providing rains

1/1/2012- Expected to be overcast with light rains 

2/1/2012 - Decreasing cloud cover and possible light rains till early morning. Rest mostly cloudy weather


Akshay Deoras
Severe Earth & Space Weather Forecaster,Astrophysics article writer.

Web-
www.akshaydeoras.blogspot.com
www.metdweather.blogspot.com
        www.scribd.com/akshaydeoras

Thursday, December 29, 2011

Landfall of Tropical Storm Thane takes place South of Cuddalore

METD WEATHER
AKSHAY DEORAS
SEVERE WEATHER FORECASTER

THE LANDFALL OF TROPICAL STORM (INTENSITY DOUBTED) HAS TAKEN PLACE AROUND 0600HRS IST TODAY SOUTH OF CUDDALORE. As seen from this DWR microwave imagery,the eyewall crossed exactly south of Cuddalore where the peak winds reported were around 115km/hr ! The winds are now expected to reverse as the half of the system has crossed

METD WEATHER HAS EXTENDED THE ALERT TOWARDS THE WEST AREAS OF THE PREVIOUSLY ALERTED REGION WHICH WILL BE NOTIFIED SHORTLY AT

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Clipper Snowfall Forecasts Lowered

48 Hour Snowfall Accumulation
Centered on Brainerd, Minnesota.
Image from Intellicast's SNOWcast.

48 Hour Snowfall Accumulation
Centered on Chicago, Illinois.
Image from Intellicast's SNOWcast.
Snowfall Forecasts for the Alberta Clipper are lowering, as shown by Intellicast's SNOWcast 48 hour snowfall accumulation forecast above. It looks like the maximum totals will actually turn out to be around 1-2 inches for South Wisconsin, with up to 4 inches in Minnesota from this clipper. I am not surprised, as it takes a lot of moisture for 4 inches of snow to fall, especially for an Alberta Clipper, which is moisture starved to begin with.

Dangerous Mistake made by Deccan Chronicle on Cyclone Thane

Well, it seems to be a non scientific post but I have pointed a dangerous mistake made by the newspaper Deccan Chronicle in their article on Cyclone Thane

The article can be seen here

Deccan Chronicle reports-

However, the storm surge is expected to be around 1 km in height and not cause much damage.


Well its a sure misguidance especially at a time of emergency like this. So people reading it please note that the correct line will be

However,the storm surge is expected to be around 1-1.5 m in height and not cause much damage

Akshay Deoras
METD WEATHER

Clipper System to Lay Down Up to 6 Inches of Snow

Maximum Possible Totals Shown
A clipper system is expected to lay down up to 6 inches in some spots of the Northern US in the next couple days. While 6 inches is unlikely, this is a maximum snowfall accumulation map.
Some notes on the map:
-Some light accumulations may occur a bit farther south than what the accumulations show above.

Signs Appearing that +AO/+NAO Regime May Break

Initial 0z ECMWF 500mb Analysis
Above we have the initial 500mb heights analysis from the latest 0z ECMWF. We see the tight polar vortex of low atmospheric pressures encircled in the black area. This polar vortex is what supports the +AO/+NAO regime. That said, if there were high pressure systems over the same black area, we would be seeing some sort of -AO/-NAO. Let's jump ahead into the ECMWF's forecast.
Hour 192 of 0Z ECMWF
At hour 192 we're seeing the Polar Vortex break apart as a ridge forces itself into the vortex from Asia. This in turn forces a low pressure system towards Greenland, making for a West Based +NAO. While we aren't showing it, this ridge does break down at the end of the ECMWF forecast timeframe. It does show that there is potential for a ridge to break in and possibly bring in some colder weather for the US.
This is another view of the top 2 images, with the analysis period at the top and the hour 192 image on the bottom of these latest 2 images.

CYCLONE THANE BATTERS TAMIL NADU COAST

METD WEATHER
AKSHAY DEORAS
SEVERE WEATHER FORECASTER

The Cyclone Thane as being mentioned in today's posts is rapidly approaching the Tamil Nadu coast at a speed of over 11km/hr!


AS OF 0730PM IST,
THANE IS AT 81E,11.8N ABOUT 100KM SOUTH EAST OF CHENNAI




Rainfall associated with it already began in Chennai late yesterday with moderate winds!
As seen from the above IR-NHC spectrum imagery, it appears that the LLCC ( Low Level Cyclonic Circulation Center) is rapidly approaching towards the area between Puducherry and Cuddalore! 


The image on the right hand side is of the Doppler Radar Chennai of 1335UT i.e 0635PM IST which clearly shows the LLCC ( Noted as circular vortex South East of Chennai in the circle of Radius 100km!) is approaching Puducherry for a head on. The radar estimates that the landfall shall be sometime tomorrow ( 30th Dec 2011) morning around 0530hrs IST


Cyclone Thane has been a Cat 1 Cyclone during the landfall which was a bit expected as it didn't had that much space where it could get weak. It shall now start weakening as it is losing the Sea surface contact. 






METD WEATHER HAS ISSUED A MARK 5 ALERT AND PDS FOR 
METD WEATHER PDS AND MARK 5 ALERT FOR THE BELOW AREAS VALID TILL 1900hrs,30th Dec 2011 

Chennai,Mamallapuram,Pondicherry,Chidambaram,Kanchipuram,Neyveli,Cuddalore,KARAIKAL,NAGAPATTINAM,THANJAVUR,TIRUCHCHIRAPALLI AND SURROUNDINGS







RIGHT- 
This is a classical example of Doppler Effect with a Tropical Cyclones in Northern Hemisphere. 
A cyclone due to coriolis force of earth's rotation rotates ANTICLOCKWISE in Northern Hemisphere. Thus the winds in the Northern half of center are anticlockwise i.e during such landfall from East the winds move towards the land( DENOTED BY BLUE COLOR IN THE IMAGE) and in the Southern Half ( RED COLOR) means winds are moving away!
























Thus PEOPLE ARE BEING INFORMED TO STAY AWAY FROM DAMAGES ESP FROM HIGH WINDS,RAINS AND STORM SURGES


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Eyewall of Tropical Cyclone BOB D1(Thane) 150km SE of Chennai

METD WEATHER
AKSHAY DEORAS
SEVERE WEATHER FORECASTER

THE LANDFALL PROCESS OF CYCLONE THANE HAS BEGUN FEW HOURS AGO RESULTING IN RAIN AND STRONG WINDS IN CHENNAI.HOWEVER THE EYEWALL IS EXPECTED TO PASS NEAR TO PUDUCHCHERRY IN PONDICHERRY TONIGHT.AS A RESULT VERY HEAVY RAINS,WINDS WILL CONTINUE PRIOR TO LANDFALL ALSO

MAJOR FLOODING ALSO CAN BE EXPECTED DUE TO THE STORM SURGE
THE ATTACHED IMAGE IS OF THE DOPPLER RADAR OF CHENNAI WHERE THE EYEWALL CAN BE SEEN AS A CIRCLE AROUND 150KM SE OF CHENNAI...

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To get Instant updates on this landfall

Wednesday, December 28, 2011

Update on January 2-4 Potential Snow Event

We've got our eye on the storm system that may go into the Northeast, the Midwest, or just move along the US/Canada border. That same storm is outlined in a gray circle above. We will be seeing it move northeast as a ridge offshore the West Coast will pump up the storm northward. This storm should push the disturbance currently on Canada's coast eastward, so both systems can go on land. Because it looks like this system is going into Canada, I'm close to ruling out a Midwest storm solution. The ECMWF/GFS models are probably right with keeping the system in Canada and not going into the Midwest or even the Northeast.

January 2-4 Potential East Coast Snowstorm Event Update

Well, the 0z ECMWF was a major disappointment. It kept the system in Canada all together, pretty much leaving the US out of the big snows that were initially possible. But for this update, we are going to say that there is a storm that might affect the Northeast- and why it might trend west instead.

NAO Forecast
The ensemble forecasts for the NAO are showing a general downturn from the positive phase towards a more neutral phase after New Years. Some ensembles are even going as far to say that the NAO will turn negative. If this were to happen, the chances of an East Coast snowstorm, in my mind, would greatly increase. However, that's a bit too far out to make a definitive prediction on. But what does all this positive NAO (+NAO) and negative NAO (-NAO) mean?
During a +NAO, a low pressure of sorts is over Greenland, which in turn moves the jet stream more north and gives the East Coast some warmer weather. In a negative phase, it is basically the opposite- we see a high pressure over Greenland give the Northeast cold and snowy weather, which is shown as an enhanced trough.
Putting those together indicates that there would be at least some potential for an East Coast snowstorm if the ensembles go as planned and the NAO moves for neutral of even negative territory.

The NAO isn't the only thing that has effects on the US. There is also the MJO. Right now, we're sitting in a moderate Phase 5 stage. We are forecasted to move into a weakening Phase 6, an almost nonexistent Phase 7 and right into the Circle of Death- when the MJO switches phases by moving in a circle in a repetitive pattern, seen by the jagged red circle in Phases 4 and 5. That is what has already happened. As we move into Phases 5, 6, 7, it comes to mind what the effects of each stage are.
Precipitation Anomalies by Phases
The stronger the Phase indicates the more these precipitation anomalies will show themselves. We are going into at least a moderate Phase 6, so let's take a look. Phase 6 includes a wet precipitation anomaly over the Ohio Valley, Southern Plains and Great Lakes, while leaving the East Coast dry. In fact, Phases 6 and 7 (the phases in which the storm will happen) both are discouraging for precipitation in the Northeast. That would provide a sort of building ground that the storm, if it is to come into the US, would affect the Midwest more than the Northeast. However, as a knowledgable weather enthusiast has said, it is a 'marriage of sorts' with the teleconnections. That means, some indices can be favorable for a storm while some are not, and the ones that are not prevail in the end.

For those wondering, the PNA is going to be moving into a very weak positive phase during this storm, per the CPC Ensembles, so I would say it might not be a factor.

As of right now, I am in a wait and see mode, as the models are having trouble with this. I am closely watching the MJO, NAO, among other indices to see if I can find some hints that this storm may or may not happen.

TS Thane is now a Category 1


METD WEATHER
AKSHAY DEORAS
Severe Weather Forecaster

Well, Category 1 Cyclone BOB D1 ( Thane) definitely intensified a bit in the last 12hrs unlike expected by METD WEATHER but since it was near the transition of Cat 1 from Tropical Storm on Saffir Simpson scale the strengthening isn't that significant

Right now the system has really gained tremendous convection momentum


The next post shall be on 29th Dec 2011 morning till then METD WEATHER EXPECTS THE SYSTEM TO INTENSIFY ATLEAST A BIT

ALERTS- 

METD WEATHER ISSUES A PDS AND MARK 5 ALERT FOR THE REGION ABOVE MENTIONED IN RED AND BLUE..


ALERT HAS ALREADY BEGUN AND EXPIRES 0800HRS IST,1ST JAN 2012

Update on Potential East Coast Snowstorm Coming Out at 12:00 PM CST Today!

An update on the potential East Coast Snowstorm- and why it may shift west- will be out at 12:00 PM CST Today! Be there!

Tuesday, December 27, 2011

Tropical Cyclone BOB D1 (Thane) in the final stages of intensification,Expected to weaken now

METD WEATHER 
Akshay Deoras
Severe Weather Forecaster

The much anticipated and quasi-stationary cyclone BOB D1 ( Thane) as expected is in the very FINAL STAGE of intensification. 
The Microwave imagery coupled with the PW spectrum imagery shows a phenomenal decrease in the available moisture around the system clearly depicting and confirmed by JTWC that Thane has exited its "Intensification Region" where there was ample of moisture to sustain robust convection!

Further the system has entered a region of much cooler SST of the order of 26-27C as against the past HIGH SST. 


The above imagery from NRL of the Brightness temp indicates the system's environment is much colder than previous and brighter convection is ongoing in the South Eastern periphery of the LLCC. 

A confirmation to the decrease in the moisture environment is depicted below from two images of 27th Dec and 28th Dec respective order. There has been a classic decrease in the PW.



The LLCC also has shrunk today unlike the broad nature of yesterday given the lacking low level convergence. Robust convection continues in the LLCC given the Poleward Outflow of 20kt. 

The overall symmetry of TS Thane indicates a peak convection cloud top temp of -70C at the LLCC aloft,two outflow channels have also developed at the North East and South Western periphery of the system… 

The banding feature also has weakened around the system!

Forecast ( Valid +12hrs 0600GMT,28th Dec)
The system is expected to WEAKEN henceforth considering the cut off from abundant moisture field,encountering cooler SST and lack of lower convergence. A marginal possibility ( IMD) of further intensification in the next 12hrs which METD WEATHER rules out. 

The system is expected to cross the Indian coast near Chennai on 29th Dec 2011 late period! 



Akshay Deoras
Severe Earth & Space Weather Forecaster,Astrophysics article writer.

Web-
www.akshaydeoras.blogspot.com
www.metdweather.blogspot.com
        www.scribd.com/akshaydeoras