Monday, December 13, 2010

Reason for Absence of Significant snowfall in J&K since two month




METD WEATHER
Akshay Deoras
Severe Weather Forecaster


Since December 2010, NO significant western disturbance has landed over Northern India
I had forecasted a western disturbance on Oct 20 2010 which brought significant snowfall in Kashmir valley and was the first snowfall of the period. After that, no such reports have arrived as no western disturbance generated had landed over Northern India
The GFS models have been indicating W.D generation and consequent snowfall/rains due to them. But the WD are passing North of Jammu and Kashmir since Oct 2010.

The snow depth maps indicate more snow North of Jammu and Kashmir than in the state itself

Reason- ( See the 2010 WINTER FORECAST FOR DETAILS. All answers embedded in that write up @ http://metdweather.blogspot.com/2010/11/2010-winter-forecast-for-india.html

Reason no 1]
LA NINA cold episodes
As was mentioned in the 2010 Winter Forecast, LA NINA cold episodes cause warmer winters in Extreme North ( J&K) . These cold episodes bring severe cold in Northern Plain state
s,Central India,Gujarat,Western Coast.

SO THERE WAS A MASSIVE COLD WAVE IN GUJARAT WHERE TEMP DROPPED TO 8C IN SURAT FEW DAYS BACK

Also, Drier winters are experienced in J%K than normal winters due to LA NINA Jet streams intensification. So less precipitation was bound to happen up there is now.
METD WEATHER FORECAST PROVES CORRECT

Relating to TIBET HIGH PRESSURE belt
Jet streams which carry these WD from Europe to Asia are still flowing in a Zonal flow indicating absence of extratropical storm. Winds aloft due to blocking high pressure over TIBET have NW or Northerly flow over Central India.

METD WEATHER FORECAST PROVES CORRECT.

2]
Secondly RELATIVELY LESS extra tropical storms( WD) are originating
in Mediterranean sea. Europe is getting hammered by the Atlantic lows and these lows are dying off after precipitating heavily in Europe

3] NEGATIVE INDIAN OCEAN DIPOLE
This parameter was not included in 2010 Winter forecast as I had not expected IOD to be Negative till so late. Neg IOD sends lesser convective activity over North India giving less Winter rains or Snowfall in extreme north of India

New models
The recently issued graphics from JAMSTEC of the Precipitation Anomaly is showing a Schematic Negative Indian Ocean Dipole in the precipitation models

Check the image above-
Blue and Red colors making a dipole in Indian Ocean

DJF Temp outlook as issued on 1st Dec 2010
DJF outlook ( December,January,February) outlook still Indicating Cooler than normal winter in Rest of India except J&K

You can see the RED ( More than AVG temperature in Jammu and Kashmir)


PROOF OF ACCURATE 2010 WINTER FORECAST OUTLOOK OF INDIA

The Image at right is the 850mb Air temperature map. The DARK BLACK LINE is the 0C line which is a divider between Rain and SNOW
Its December mid but still the 0C line has not covered Northern India meaning that Air is still warmer than 0C ( AS THE FORECAST MENTIONED FOR 1C ABOVE AVG)

Surface temp are low in J&K but atmospheric temperature at 850mb is still warm to convert rain to snow and also NO MOISTURE PRESENT FOR IT

3 comments:

  1. Your prediction about winter pattern are spot on.I am from mumbai & following your blog for last 6 months.Even in mumbai it getting chilly.On monday temp. drop to 14c. What your prediction for mumbai, will mumbai temp will drop to below 10c just like 2008. It will be great if you put on weekley forecast for mumbai.Cheers.

    ReplyDelete
  2. Thanks for those valuable comments!
    I am sorry first of all for the late reply.

    Yes. Mumbai is getting chilly as per the La Nina forecast coupled with Neg.IOD. To make a temperature forecast is quite difficult but I do think that Mumbai will witness temperature upto 10C atleast this season. 2007-08 was a La Nina year and as you say that temp was below 10C, its possible this year also.
    For Mumbai forecast ( weekly) I will think on it .
    Thanks for the following. It will be better if you connect with METD WEATHER through facebook

    http://www.facebook.com/pages/METD-WEATHER/375172700693

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  3. My senior Colleague Rajesh Kapadia forecasts Mumbai weather at
    rajesh26.blogspot.com

    This will be useful to you !

    ReplyDelete