Never-before-seen footage of the August 28, 1990 Plainfield, IL supercell from DeKalb

[sebenste]

Hello everyone,

On a very hot and extremely humid late August day in 1990, a thunderstorm
rapidly became a supercell and produced at least two known tornadoes.
One was near an Illinois State Police outpost near Pecatonica, IL captured by a
news crew in Rockford at around 1:30 PM. It then went southeast
over DeKalb, producing hail the size of golf balls and bigger at DeKalb around
2:45 PM. Then, of course, it produced a devastating
tornado in Crest Hill, Plainfield, and Joliet, IL around 3:15 PM
on that fateful day...August 28, 1990.

Unbeknownst to us all, a young man by the name of Jay Orbik,
then a helper at NIU Media Services, grabbed a professional
video camera and tripod and ran to the top of the Huskie
Stadium with two associates as the storm approached.
Jay never caught the Plainfield tornado, and apparently never
thought the video was of great worth. He did say he saw a brief
spin-up just south of the stadium that my current boss saw lift a
half-full heavy dumpster and throw it across the road. Alas,
Jay was moving the camera and didn't catch it except with
his eyeballs. I am still left to wonder if we had an EF-0 here
on campus with that supercell, but the evidence is mounting.
All that said, I was talking with Jay in a casual Facebook
conversation about my chase that day, and he told me of this video.
When I saw it, my jaw dropped. With his permission, he has graciously
allowed me to make it publicly available to one and all. And
with his permission, I have uploaded it to my YouTube account for
everyone to see. The first part of the video is the most interesting.

WARNING: Contains adult language and intense storm video. Parental guidance is
therefore suggested.

http://www.youtube.com/watch?v=WP9EcNAPGJs

 

[Skip Talbot]

Wow, thanks for sharing this Gilbert. That event sparked my interest in severe weather and tornadoes as it left a very deep impression on me at a young age. What a beastly HP. I'd hate to try and chase that thing, especially through those areas that have now really been built up, and of course dealing with the devastation and tragedy afterwards.

 

[Bob Hartig]

What a find! Any video from the 1990 Plainfield storm is gold, if for nothing more than its historic value. I love those first few seconds that capture something of the storm structure. Thanks, Gilbert!

 

[Simon Andersen]

The storm actually produced five known tornadoes, none of them near Dekalb. The video was shot at the onset of a downburst cluster to the southeast in which an embedded mesocyclone produced four tornadoes, the strongest of which was rated F2. This according to Fujita anyway.

 

[joel ewing]

Plainfield, Illinois Supercell

I'd like to add my thank-you for making this video available to us, Gilbert. What an incredible find!
If memory serves me correctly, I think this tornado really caught people off-guard, didn't it? Especially since it was so late in the summer.

 

[rdale]

Well it caught them off guard because no warning was issued. Part of that was the fault of the NWS office, part was the fault of the spotters. They now have a VERY active and wide ranging spotter system in that part of the state. Fujita's report on this is at http://books.google.com/books?id=o9... maddox&pg=PA1#v=onepage&q=plainfield&f=false

 

[Bob Hartig]

I believe this was a northwest flow event (correct me if I'm wrong). Illinois seems to have a penchant for producing tornadoes out of northwest flow--case in point: the Roanoke tornado--but the Plainfield tornado was in a league of its own. I just dusted up on a few details of this storm. CAPE (I'm assuming SB) was 8,000 J/kg, and the LI was between -12 and -14. That is some absolutely jaw-dropping instability. It's a wonder the whole landscape didn't get sucked into the vortex, given those conditions.

Regarding unpreparedness, the Wikipedia article says this: As the Chicago office was overwhelmed with its workload, no warnings were issued by the office until 2:32 p.m. — nearly an hour after the first tornado was sighted southeast of Rockford. A second severe thunderstorm warning was issued almost an hour later at 3:23 p.m., but this provided no indication that a tornado was on the ground and did not mention the area where the tornado had tracked. No tornado warning was issued until after the tornado lifted.

The article mentions that the Chicago office got raked over the coals for its failure to issue warnings for a catastrophic tornado. But it also mentions that the office was badly understaffed and overstressed that day.

 

[rdale]

Bob Maddox (SPC) wrote an excellent analysis of the situation, similar to the NWS Service Assessments that are used these days. Purdue had just started back into session and we were ready for a big chase locally, but everything seemed to converge over northern IL so we could see the blowoff but nothing exciting came our way.