5/17/06 NOW: WI/IL/IN/MI

[David Draun]

There are lots of storms out there with warnings, especially in SE Wisconsin. A nice bow echo is now riding south down the lakeshore toward Milwaukee and Chicago with some isolated convection out ahead and west of it. Instabilty that has developed is greater than what was originally forecasted with LI of -4 and SBCAPEs over 1000 J/kg in a few areas according to the mesoanalysis. It looks like the main threat is hail with the cold pool aloft. We are back in the sunshine over here, after a gusty shower, and it's warming back up nicely

LOT NEXRAD is still out! <_<

I couldn't help myself, lol. I just took a picture of the line of rock-hard updrafts to my NW.

 

[Kevin Bowman]

KLOT radar will be out possibly till friday, they are upgrading the radar and all that. they said it should be up today but possibly might be out till friday

 

[MatthewCarman]

Dewpoints are only in the 45-55 range across alot of wisconsin,Illinoise and Iowa. Having that said humidity is high and a cold front is pushing into 70 degree temps with lots of moisture. Storms are producing penny to nickle size hail and winds 50-58 mph with most of the storms. Nice bow echo moved through the milwaukee area but have heard no reports of any damage. The SPC outlook has a 2% chance for tornadoes does anyone think we may see a tornado or 2 today?

 

[J West]

Just heard multiple reports of a funnel moving over the east side of the City of Racine, out over Lake Michigan. These were both "Copnadoes" called in by a sheriff deputy and a firefighter, however the MKX met was doing a hard cross examine for details (which they rarely do) so it sounds legit. No warning at this point.

The line passed over here, and there was a defined updraft off to my west but everything has an elevated base and is pretty bland looking.

 

[samuel stone]

as crazy as it sounds I dont think a weak tornado is out of the question in northern illinois, reason 1) dew points are low yes, but LCL's per spc meso analysis are around 1400 in northern illinois wich is still "doable" for tornadoes. reason 2) yes we have northwesterly flow, but keep in mind surface winds are out of the west so the downdraft will will not effect the inflow as much as if surface winds were out of the south/southeast, which means they may not be quite as outflow dominate as it may seam. 3) look at the proximity to the very cold 500 mb low we could have a cold core event on our hands.

That said, low dewpoints will still promote colder downdrafts through evaporational cooling, which may still compromise updarfts enough for storms to remain outflow dominate. Plus helicity although not bad does leave a little to be desired.

So yeah chances are low but there is still a possibility of a waek tornado.

 

[David Draun]

The tail end storm NE of Rockford, IL looks like it may be developing a hook. There's no shear couplet though. Outflow boundaries surging southward are showing up beautifully on the relative velocity displays.

http://radar.weather.gov/radar.php?rid=MKX...101101&loop=yes

 

[rdale]

Low-level winds are VERY weak, combined with LCL's pretty high up there, so it'd take quite a bit to bring down a TOR. The 2% is just a token.

"The tail end storm NE of Rockford, IL looks like it may be developing a hook"

That's not a hook related to any sort of rotation.

 

[Kevin Bowman]

The tail end storm NE of Rockford, IL looks like it may be developing a hook. There's no shear couplet though. Outflow boundaries surging southward are showing up beautifully on the relative velocity displays.

http://radar.weather.gov/radar.php?rid=MKX...101101&loop=yes
[/b]

to me it just looks like storms continuing to form along outflow boundaries

 

[David Draun]

THE NATIONAL WEATHER SERVICE IN LINCOLN HAS ISSUED A

* TORNADO WARNING FOR...
WESTERN WOODFORD COUNTY IN CENTRAL ILLINOIS
PEORIA COUNTY IN CENTRAL ILLINOIS
STARK COUNTY IN NORTH CENTRAL ILLINOIS

* UNTIL 530 PM CDT

The storm looks fairly impressive on radar. There is almost a "flying eagle" appearance to the cell. It is heading toward Peoria, IL

 

[rdale]

A "flying eagle" is referring to a V-Notch type appearance - this cell doesn't have that. It's got an interesting overhang on AE, and nice notch on the southeast side (hard to reorient based on that motion ;> ) but rotation pretty anemic.

SVS says the possible tornado is near Peoria - but the storm itself is still more than 10 miles NW of PIA?!?

COR just fixed that to say "Princeville" instead.

Lon Curtis has some nice flying eagle samples: http://www.vvm.com/~curtis/May6/May_6.html and http://www.vvm.com/~curtis/Radartechs.htm

 

[Kevin Bowman]

just had some marble to quarter size hail, covering the road

Golf ball size hail at wrigley field

large hail reported in downtown chicago on michigan avenue (wgn)

 

[Tony Lyza]

I'll be leaving on my first chase momentarily. We'll be chasing that intense cell that just passed over Kevin. I think that a lake breeze may be guiding that thing and aiding in it keeping its intensity.