Lake Breeze Helicity

[Bob Hartig]

I thought folks here might find the attached radar grabs interesting. Right now there appear to be a couple storms firing up by Chicago withing the lake breeze zone. You can see a couple things going on, the most immediately evident being the boundary set up by the lake breeze itself. Nice line of convergence there, where the overall westerly surface flow butts up against the onshore breeze. A closer look at wind barbs reveals backing winds as high as 40 knots feeding into the northernmost cell.

Michigan gets a lot of this kind of lake-induced action. Depending on the time of day, you can find localized helicity to the west or east where you wouldn't normally find it. I'm sure this is why I often see a small sigtor in Berrien County.

EDIT: I regret that the attachments are too small for you to be able to make out the wind barbs very well. For those who are interested, I've posted a similar but more detailed article with larger and more images in my blog.

 

[Adam Lucio]

Those storms gave my neighborhood its second beating by severe storms in a week, as those who are my friend on facebook know. I posted a bunch of damage photos, entire trees down ontop of cars in my area. A large limb flew off my neighbors tree and landed on my front lawn, luckily missing my truck.

The two branches on either side of the sidewalk were from the storms 6 days ago, along with the new damage.

3 blocks north of my house.

Lots of other trees down too but I wont post all the photos. Powerlines, fences, shingles and sheet metal were strewn about the area and the roof at my form highschool was ripped off along with the dugout being overturned which injured a couple people.

Lake Michigan does screwy things with our weather here, usually it kills most storms with its cooler stable air but there have been ocurences such as yesterday where the influence of the lake can actually cause storms or strengthen ones moving into the area.

Three years ago a weakening storm spit out an outflow boundary which interacted with a lake breeze and spun up a brief tornado. I remember LOT put out a news article asking for the witness to come forward and provide details. Here is the event write up for that day.

http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=lot&storyid=13600&source=2

I was at work [in the loop] during the assault so I missed the main show yesterday, but the sears tower repeatedly getting struck by lightning and the earth shaking thunder that follows is always a treat. I have a spot where I can sit and watch the show.

 

[Bob Hartig]

Geeze, your neighborhood got slammed pretty good. No fun cleaning up that mess!

Lake Michigan truly is a weather influence. I've seen any number of burly storms in Wisconsin, including supercells, crash and burn over the lake. On the other hand, the lake breeze zone can play some funny tricks.