rdale
EF5
Gotcha - thought you were photogrammatically analyzing the raindrops ;> I think anything will be cleared up once we see the damage pics.
Sorry guys, I really don't have damage pics. It's all cleaned up, and I ran off to chase another cell in IL soon after our storm passed over. Geez, I gotta stop being an airhead and do what need be done.Gotcha - thought you were photogrammatically analyzing the raindrops ;> I think anything will be cleared up once we see the damage pics.
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Hi Alex!Hey Tony,
We always get really excited when something is "happening in our own backyard" (I myself am guilty of this on many occasions) so some tend to turn into a reporter, trying to inflate the story for the best scoop (lol also occasionally guilty). Weather weenies like outdoing each other's stories methinks, so the reporting is probably an offshoot of that. So what I have learned to do is to first take a step back and refresh my brain and then look for only what I am SURE I am seeing. In this case it appears to be a wall cloud or gust front (stills don't show rotation so I can't say either way) and your estimated wind gust speed. Then I look for anything suspicious to make sure I'm not missing anything. However, unless you're reasonably confident in your observation its better not to call it in IMO and watch it to become more certain. I mean a rotating wall cloud is a rotating wall cloud and if you see an obvious one you should call it in, but if you just see a suspicious lowering from a distance...that can be in the grey area that I am talking about. A false tornado report would mean an extra trip out and more work for the NWS folk. IMO I don't see a tornado in there at all so I would have called in the wind gust estimate and perhaps made a note to tell them that i saw a cloud formation that looks suspicious but I cannot tell if its a rotating wall cloud yet (or something thereabouts).
Never heard anyone ask me for a second verification on my report before...that was strange. I wouldn't beat yourself up too much about it. Just roll with the punches and remember that we all get excited in the heat of the moment!
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"I knew it was at least a wall cloud because it was in the updraft of this odd storm."
Finding it near the updraft does NOT mean it is a wall cloud.
"confirmed it on Doppler radar"
The radar image you posted does NOT show rotation, and it certainly wouldn't be picking up rotation in a wall cloud.
I would not take Tom Skilling's "confirmation" of the above pic being a wall cloud as a real confirmation. There are PLENTY of chasers with MUCH MORE experience than Tom who already explained to you why that can't be done with a simple still photo.
What type of damage was done? At the least that awning should be a long way away from your neighbor's house and his yard furniture should be downstream too.
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Hey Nick!Alright, I went ahead and downloaded some WSR-88D data from KLOT during that selected period... The storm was obviously just a pulse storm, and exhibited linear structure on radar. You have to remind yourself that the day had ~10kts deep-layer shear at the very most, and extreme instability (for most of the region) -- and even in most cases when a lake breeze boundary is involved with this type of background environment -- you'll still get multicellular/pulse deep convection (which would be capable of damaging downbursts, and large hail given the extreme CAPE associated with the parcels ingested). I'm looking at the scan at the time of the 75mph report over Schererville (IN) and the only thing I could even see in the velocity scan (in every tilt) would be just a tad of horizontal shear along the thunderstorms gust front between Highland and Gary.
The thunderstorm weakened rapidly as it pushed northeast towards Lake MI towards 2140 UTC, as it moved away from the instability on land (which was augmented by the excessive insolation/diabatic heating and considerable low-level moisture). It was your typical multicellular/linear-type structure that you'd see on days like this. According to the KLOT SVR issued for Lake Co, another spotter reported a 75mph gust further west in Will Co.
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Thank you for that valuable information, Beau! Unfortunately, my problems with LOT did not stop with this storm. As I mentioned in a previous post, my chase team and I embarked on a very short chase after this bad storm. We went to the south suburbs of Chicago, where we observed several areas where the roadways were covered with up to 8" of water. I called in the report, making sure to identify myself as a storm spotter. I gave my observation, the town, even the actual streets where the flooding was taking place. Still, an LSR was never written on that report. So, I understand what you are saying, but that still doesn't lessen my feelings toward LOT in this incident.I volunteer at the WFO in Minneapolis, MN and work many of the severe events... And for what its worth, that forecaster was likely doing his job in not filing the LSR. We have been instructed to only file wind LSRs with specific (Meaning 10" Diamater Branches...Siding ripped off home etc) damage. Wind speed is only to be put into an LSR when the winds have been measured with an anemometer.
Humans are simply terrible at estimating wind speed, myself included. We almost always waaaay overestimate the wind even when we try our best to be conservative with our estimates.
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