Topic: Bangadesh - violent storms 2005 2006 - discussion

[Jimmy Deguara]

Hi,

I was reading this article that David had alerted us to previously on this forum.

http://www.bangladeshtornadoes.org/bdfcsts05/032005/tornadoinfo.txt

Given the extremely unstable atmosphere and explosive development of updrafts, I am interested in determining what might have occurred in this tornadic case:

      Our Gaibandha correspondent reports: The tornado followed by a hailstorm tore down over 500 houses and uprooted
      numerous trees and electric poles in three unions under Sadullahpur and Sundarganj upazilas in the district.

Tornado followed by hailstorm alerted me to the behaviour of Jarrel Texas tornado outbreak. Although not identical in terms of windshear parameters, this is particularly interesting given the outflow boundary retreating southwestwards thence leading to perhaps a more southerly trajectory of the storm - tornado followed by hailstones. Was there perhaps a backbulding component?

What are your thoughts?

Regards,

Jimmy Deguara

[Jimmy Deguara]

HI,

I just noted the tornado paths map:

http://bangladeshtornadoes.org/tornadopaths/bigmap.jpg

A lot of tornado paths reflect this southerly trend in fact some head SW which adds substance to the argument above.

Regards,

Jimmy Deguara

[nmoir]

One other feature of this map is interesting , most reports are so close to the capital Dhaka , makes me think that much data is missing or unreported away from the city ,  perhaps the only weather radar is at Dhaka and it is also where the meteorologists are based and they dont go into outer districts?

[Jimmy Deguara]

Hi Nick,

A good observation regarding data around the major city. However, being such a populated country, I doubt whether it is the lack of population as compared to lack of perhaps understanding/education that may be an issue here. The media perhaps the media is a factor not so concerned about what happens well out of the population centres unless something very significant happens.

Climatologically though, most of the serious storms that become tornadic seem to occur in the region anyway. Further west, along the dryline, perhaps hail is more likely. There is an interesting article that links the consistency of outflow boundaries from convection in the hills of northweastern India near Cherrapunji (one of the world's wettest spots) as an important component in aiding storm initiation and tornadogenesis. Imagine the lightning from a storm tapping 9000 to 10000 CAPE!

Regards,

Jimmy Deguara

[nmoir]

the death rates could be far higher than in USA because of poor construction , pop density and no warnings and poor hospital care , you could imagine the devastation that a big wedge would do to villiages and slums , there would be nowhere to hide . scary stuff

as to your original question i would have to have someone hold my hand looking at the data to understand it i think , and where do you go for bangladesh info?

[Jimmy Deguara]

Hi Nick,

That same website from Jonathan Finch has forecasts and warnings for Bangladesh - I am assuming he has taken on this role out of a hobby/research and interest in the region?

http://www.bangladeshtornadoes.org/

One could use the same model data as well used here in Australia but given the lack of consistent data/soundings I am not sure about how reliable the models would be? David might like to elaborate further in his studying of the conditions over the past cuple of seasons.

Regards,

Jimmy Deguara

[nmoir]

thanks for that , will have a good look when i have time