Cold air funnels reported over Huntsville, AL

[Brent]

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1248 PM CDT THU APR 7 2005

ALZ006-007-071815-
MADISON-MORGAN-
1248 PM CDT THU APR 7 2005

...FUNNEL CLOUDS HAVE BEEN REPORTED OVER THE CITY OF HUNTSVILLE...

NUMEROUS REPORTS OF FUNNEL CLOUDS HAVE BEEN REPORTED OVER THE CITY OF
HUNTSVILLE. THESE ARE NOT TRUE TORNADO FUNNELS! THESE FUNNEL CLOUDS
ARE THE RESULT OF VERY COLD AIR ALOFT...ALONG WITH THUNDERSTORM
DEVELOPMENT.

THESE FUNNELS SHOULD REMAIN ALOFT THROUGH THE EARLY AFTERNOON.
HOWEVER...A BRIEF TOUCHDOWN BY A FUNNEL COULD CAUSE WIND DAMAGE...
ESPECIALLY TO WEAK BUILDINGS SUCH AS SHEDS.

MORE FUNNEL CLOUD DEVELOPMENT IS POSSIBLE OVER MADISON AND MORGAN
COUNTIES OF NORTHERN ALABAMA. STAY TUNED TO NOAA WEATHER RADIO FOR
LATER STATEMENTS.

VERY unusual.

[JenBayles]

OK. Somebody educate me. When is a funnel not really a funnel? I don't get it!

[GalvestonDuck]

OK. Somebody educate me. When is a funnel not really a funnel? I don't get it!

http://www.tpub.com/content/aerographer ... 269_27.htm

The turbulent action along the cold air outflow boundary may produce small-scale vortices on the ragged base of the roll cloud. These vortices sometimes take on the appearance of small, ragged funnel clouds. The public commonly mistakes these vortices for funnel clouds and occasionally reports them as funnel clouds. These vortices are known as cold-air funnels. Rarely, a cold-air funnel will develop sufficiently to reach the surface. It does not have the strength of a true funnel cloud or tornado, and is about as powerful as a strong dust devil. By itself, it may be able to pick up objects, such as trash cans or to shake a small camp trailer. Usually, the damage associated with sightings of cold-air funnels is caused by the much more powerful straight-line winds in and behind the outflow boundary (gust front) that produced the cold-air funnel.

(That's gotta be a first -- how often do I get to throw out weather-related answers being the non-meteorologically minded person that I am? )

[Brent]

If they touch down, they are compared to a Gustnado(which happen on the leading edge of squall lines sometimes) or a dustdevil. It's very odd. I can only remember one other incident 2-3 years ago. There are also showers occurring that are producing small hail, despite no thunder/lightning.

[JenBayles]

Cool! Thanks for the new brain wrinkle.

Dave & I about got blown off the bike by a dust devil in New Mexico. Felt like getting clobbered by a mattress.

[GalvestonDuck]

Cool! Thanks for the new brain wrinkle.

Dave & I about got blown off the bike by a dust devil in New Mexico. Felt like getting clobbered by a mattress.

And how often have you been clobbered by a mattress?

[JenBayles]

Cool! Thanks for the new brain wrinkle.

Dave & I about got blown off the bike by a dust devil in New Mexico. Felt like getting clobbered by a mattress.

And how often have you been clobbered by a mattress?

I never kiss and tell.

[DocMonks]

The description below (and associated reference) is NOT what is normally termed a "cold air" or "cold core" funnel. Cold air funnels typically develop underneath rapidly developing cumulus congestus (and sometimes cumulonimbus) in an atmosphere of unusually cold air aloft, usually in the summer (but can occur in spring/fall).

When these funnels touch the ground they are, in fact, tornadoes, albeit quite weak.

A brief description is available at <http://www.theweatherprediction.com/habyhints/329/>

Doc

OK. Somebody educate me. When is a funnel not really a funnel? I don't get it!

http://www.tpub.com/content/aerographer ... 269_27.htm

The turbulent action along the cold air outflow boundary may produce small-scale vortices on the ragged base of the roll cloud. These vortices sometimes take on the appearance of small, ragged funnel clouds. The public commonly mistakes these vortices for funnel clouds and occasionally reports them as funnel clouds. These vortices are known as cold-air funnels. Rarely, a cold-air funnel will develop sufficiently to reach the surface. It does not have the strength of a true funnel cloud or tornado, and is about as powerful as a strong dust devil. By itself, it may be able to pick up objects, such as trash cans or to shake a small camp trailer. Usually, the damage associated with sightings of cold-air funnels is caused by the much more powerful straight-line winds in and behind the outflow boundary (gust front) that produced the cold-air funnel.

(That's gotta be a first -- how often do I get to throw out weather-related answers being the non-meteorologically minded person that I am? )