Illinois Hurricane radar loop, 8 May 2009

www.youstorm.org - A fascinating hurricane like organized mesoscale convective system over Illinois with eye like feature and comma rainband. Discussion here:
http://www.weather.com/blog/weather/8_19404.html

Category:

Science & Technology

Tags:

• illinois
• kentucky
• iowa
• hurricane
• storm
• tornado
• radar
• May
• 2009
• thunderstorm
• weather

[stormdude3603]

We all agree that to be classified as a tropical systems, that those conditions must be met, along with the strongest sustained winds near the center of the storm, not far away from it. There were never sustained winds of 39 mph or greater with this storm, let alone 74 mph. Embedded within the derecho, there were very strong wind gusts caused by microbursts and downdrafts. This is no tropical system. Merely a strong area of low pressure that peaked during a period of intense convection.

[bwlfp]

@stormdude3603 I think you may have defined a tropical system

[stormdude3603]

Very impressive storm to be sure. Very large derecho. This, however, was NOT A HURRICANE. It was a very well developed mesocale convective system with a large derecho/bow echo. There is a very convenient void in convection where the "eye" is. The motion around this void is barely moving counterclockwise, not the violent spiral that a hurricane is. We all agree that tropical systems are borne in the water and not over land. We all agree that tropical systems are purely warm-cored. 

[bwlfp]

@stormdude3603 not sure in fact some of the elements of genesis are being discovered through land systems. Perhaps the fundamental elements of a hurricane can occur over land but are unlikely to be maintained? Recent research suggests that the fundamentals lie in the convection not the ocean.

[bwlfp]

@lionsforlyons I did not contradict myself at all, try re-reading my sentence. Tropical cyclones do not have to form in the tropics. I am not saying this is a tropical cyclone, however it may exhibit similar features to a forming tropical cyclone.

[bwlfp]

@lionsforlyons Tropical cyclones don't have to form in the tropics it's just that they usually do.

[bwlfp]

@lionsforlyons tropical cyclones form from mesoscale convective vortices.

[JustinUstynik]

This is a Low Pressure area not a Hurricane or any assoicated tropical event. A tropical event originates over the warm waters, this event did not. However it does not matter. The winds, if correct at over 100 mph, are equal to a catagory 2 hurricane even though the winds last for only a few minutes - and that 100 mph is in very short gusts.

Hurricanes have short gusts as well that are much stronger than the sustained winds.

[stormdude3603]

In Texas, we see these radar echoes quite frequently. A large thunderstorm complex will develop, and behind it, a low pressure area will trail often giving the impression of a tropical-like storm. To the lehman, this was an "inland hurricane". To weather afficionados, meteorologists, and newspeople, this was a strong MCS with an intense derecho.

[wac4zac35]

This day sucked! i was at school in benton illinois. sometime around 11 o clock we got into the tornado position in the hallways and bathrooms and stayed like that all day. i was terrified. it was the worst day ever. Then when we got home we didnt have any power for three days. but we were lucky cuz in marion n carbondale they didnt get power for like a week!