Tuesday, 23 November 2010
Tornadoes cause damage in Illinois and Wisconsin yesterday…
It turns out I was right in being quite impressed with the severity of the tornado setup yesterday in Illinois. There were a total of eight tornado reports from northern Illinois into southern Wisconsin. Three people were injured when a reported half mile wide tornado passed near Loves Park, Illinois. Click on the YouTube video below to see the tornado at a different stage in its life as it passed by Loves Park.
Loves Park tornado video by John Farley
http://www.youtube.com/watch?v=dEgbm-t0_As
The Loves Park, Illinois tornado was produced by a low topped supercell. An unusually high amount of CAPE was available for this setup as RUC estimates were in the 500-1000 J/KG range around the time when the tornado occurred. Low level shear was very high, so it’s not surprising that a sizeable and possibly violent tornado occurred (the tornado has not been rated as far as I know).
I will say this — the tornado bears a striking resemblance to the Gilbert, Iowa tornado I chased back on November 12, 2005 (see videos below). And I’m not just bringing it up to toot my own horn! Both tornadoes were short stovepipes with that violent wavy motion on the sides. They were both ‘short’ because the surface temperature was not very warm (lower 70s), but the dewpoints were in the lower 60s! So the cloud base on both days were quite low, and the reason why both tornadoes were so stubby. And both tornadoes were produced in November from low topped supercells that formed under high shear yet unusually high amounts of CAPE, given that type of setup.
The big difference between the two events, however, is the Loves Park, Illinois tornado formed from a storm that develop ahead of an arctic cold front. I will also say the Loves Park tornado visually LOOKS stronger than the Gilbert Iowa tornado. Whether or not that means a higher rating — I just don’t know. A damage survey will provide us with that answer.
Below are two clips of the Gilbert, Iowa tornado for an interesting comparison between it and the Loves Park tornado. Both tornadoes were produced from low topped supercells in neighboring states in November under similar conditions.
Gilbert, Iowa tornado November 12, 2005 (part 2)
Gilbert, Iowa tornado November 12, 2005 (part 3)
I’d love to see additional video of yesterday’s tornado in Loves Park, Illinois. But based only on John’s video shot from what appears to be at least two or three miles away, I can’t imagine that tornado being rated lower than EF2.
So once again, 2010 brings yet another photogenic tornado!
- Jim