85 dead in Indian tornado

[MJ Poore]

85 dead in Indian tornado and/or wind event

Killer tornado slams India
by Associated Press Apr 14, 2010 5:22 am ET
CALCUTTA, India (AP) - A cyclone packing winds of more than 100 mph (160 kph) demolished ten of thousands of mud huts in northeastern India, killing at least 85 people, officials said Wednesday.

The cyclone struck Tuesday night in northeastern parts of West Bengal and Bihar states, uprooting trees and snapping telephone and electricity lines, West Bengal Civil Defense Minister Srikumar Mukherjee said. Hundreds of people were injured.

Television footage showed uprooted trees lying across shanties and sheets of corrugated metal ripped from the roofs of homes. Small children sat outside their damaged huts as parents tried to salvage their belongings from inside...

--> CLICK HERE TO READ MORE

 

[Scott Olson]

I'm going to see if I can get the archived radar. I've always had a great interest in this region and have planned for years to do an expedition. Jonathan Finch contacted me this morning to express his thoughts that this was a derecho.

From India Meteorological Department:

causing moisture incursion over West Bengal. Satellite imagery of 1730 hrs IST on
13 showed deep convective clouds over East Bihar and Sikkim areas. It led to the
development of a severe thundercloud called cumulonimbus with its height upto 14
km. The clouds containing multiple cells got intensified and moved in East to South-
__________________________________________________________________________________________________
Mausam Bhawan, Lodi Road, New Delhi – 110 003
Phones: 24611068, 24618241-47; Fax No. 24699216, 2423220, 24643128
easterly direction. At 2247 hrs IST the vertical extent became more than 18 km. The
distance of the multiple cell system from Kolkata was 408 km in North-Northwest
direction. The cloud system further intensified into a squall line structure at 2317 hrs
IST and moved over Bhagalpur and Purnia region in Bihar and adjoining North
Bengal region. At 2332 hrs IST, the intensity of the system was maximum and this
is the probable time of devastation due to strong downdrafts with wind speed might
be exceeding 100 kmph. Thereafter, the system moved away and entered
Bangladesh almost in a squall line formation but with reduced intensity. Over all
duration of the system was about two hrs.
This severe thunderstorm with large vertical extent may be associated with a
tornado and the damage caused may be due to tornadic rotation associated with the
severe and tall thunderstorms.​

Affected Districts

The key word is squall line. Also observe the damage path is quite extensive. Being such a progressive derecho you can probably count in some mesovortices. Add in the fact that most of the homes in that region are simple structures of tin with barely any anchor and you have a recipe for disaster.

 

[W. Grant Dade]

I have not been able to find archived radar data but based from satellite images it does appear this was a broken like of storms, not a squall line when the damage took place. Also the regional meteorological center is calling it a tornado as well. A little surprised to hear the estimated top winds were only 125km/hr or around 78 mph, based on the damage reports (down form 100mph. Communication break down?). I did a blog on the event with a satellite image and loop.

Scott I would love to find some radar data from these storms. Let me know if you find any.

http://gdadeblog.blogspot.com/2010/04/tornado-hits-india.html

 

[Marko Korosec]

I was browsing the skew-ts of the nearest stations there, see here:

Calcutta: http://weather.uwyo.edu/cgi-bin/sounding?region=seasia&TYPE=GIF%3ASKEWT&YEAR=2010&MONTH=04&FROM=1200&TO=1512&STNM=42809

Dhaka: http://weather.uwyo.edu/cgi-bin/sou...AR=2010&MONTH=04&FROM=1200&TO=1512&STNM=41923

Also, today it seems that another trough with an impressive system is just passing those areas again:

http://www.imd.gov.in/section/satmet/dynamic/insatnequad-ir.htm

Its interesting to note that this time of the year, actually April 15th +/- 2 weeks is the peak season for robust severe weather there. See here: http://bangladeshtornadoes.org/climo/btorcli0.htm

EDIT: just found many more data... still no luck with archived radar images:

official report: http://www.imd.gov.in/section/nhac/dynamic/pressrelease.pdf
satellite archive: http://202.54.31.45/archive/NORTHEAST-SECTOR/

 

[Marko Korosec]

Found the radar loop of this event in Jeff Master's blog on Wunderground:

http://www.wunderground.com/hurricane/2010/india_tornado.gif