11/08/05 NOW: Great Lakes/OH Valley

[Mike Johnston]

Convective Initiation! Will open NOW thread for this very interesting day. Isolated cell over White County, Ind. w/ 55dbz core just popped up - a sign of events to come overnight, or just an anomaly?

 

[David Draun]

It must be a slow rumble, KLOT's doppler is still in clear air mode. The position of the warm front reminds me of 4/20/04. Just give it a couple hours, and a few tiny, but dangerous supercells will pop south of CHI.

 

[Kevin Bowman]

It must be a slow rumble, KLOT's doppler is still in clear air mode. The position of the warm front reminds me of 4/20/04. Just give it a couple hours, and a few tiny, but dangerous supercells will pop south of CHI.

that is exactly what im thinking

severe tstorm watch issued till 3am for all of northern illinois

 

[nickgrillo]

Convection should slowly increase through the next few hours... With the eastward progress of the shortwave continuing and now moving into the area (IL / WI). Surface frontogenesis is occuring -- with a strengthening warm front currently lifting northward across central IL/IN... Mixed-Layer CAPE is currently 500-1000j/kg across the area. Low-level shear has increased dramtically within the past couple of hours... 0-3km SRH is currently a widespread 250-400m2/s2 across central/northern IL and IN, with the 50F SFC Td gradient currently moving into northern IL.

Any sfc-based tstms that sustain themselves near the warm front will be capable of tornadoes, very large hail and destructive winds.

 

[Terry Kollmeyer]

Hopefully! I'm sitting on the warm front, here at home. I agree with you, Dave regarding 4/20/04. I'm taking things one step at a time, though.

0-1km Hel. currently 300m2/s2, LCL's 800 mtrs, 0-6 shear 55 kts. 0-1km shear 25 kts should help make up for the lack of CAPE.

Td's here in La Salle Co. in mid 50's,

 

[Eric Chambers]

I'll be up all night watching this, and hopefully we will see something interesting. We have not had much in the way of Severe Weather this year in Michigan. Just maybe......


Hello Nick!

 

[Mike Johnston]

Keep out a sharp eye just S of the watch box also. Over N KY, where pressure height lines are most perpendicular to isotherms, and therefore CAPE pooling. Severe indices building here, right around base of negatively tilted surface pressure gradient.

 

[Eric Chambers]

Severe Thunderstorm Watch #853 in effect untill 0300 for SouthWest Michigan......just might happen yet(I am one county outside of the watch, I am in Washtenaw County!!!

 

[Andrew Khan]

Tornado watch to last until 1:00 AM. Cells just blew up near Grant County, IN, with some VERY high dBZ values in the 62.5 range. I really hope this does not turn linear, already. I would really say hail is coming down hard in Grant County, size perhaps, 0.75 -- 1.00 in, or something.

 

[Mark Farnik]

Small line of cells is erupting from just east of Logansport to southeast of Marion, Indiana with nastiest cell in the line about to smack into Marion ATTM. Strangely enough there are no warnings with this cell. That may change shortly, however. Stuff in Indiana is already going linear; I still think northern east central Illinois is going to be the place where more isolated cells, possibly with tornadoes, are most likely to form-hopefully no late night nasty suprises like on Sunday night

 

[Andrew Pritchard]

Storm cluster is organizing nicely in central Indiana.. just got a Severe Thunderstorm Warning for Grant and Blackburg Counties. Probably some decent sized hail in there.

EDIT: Sorry, Blackford County, not Blacksburg..

 

[Mark Farnik]

This just in:
THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
BLACKFORD COUNTY IN INDIANA
SOUTHEASTERN GRANT COUNTY IN INDIANA

* UNTIL 945 PM EST

* AT 833 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL. THIS
SEVERE STORM WAS LOCATED NEAR JONESBORO...OR ABOUT 3 MILES SOUTH OF
MARION...AND MOVING EAST AT 25 MPH.

Good guess on the hail size, Andrew.

 

[Kevin Bowman]

storms going up over the lake east of racine and in northern indiana in st joseph county

 

[J West]

There are now some faint returns that have appears in the last few scans on the MKX radar SSW of MSN down towards RFD, and some actual convection firing over Lake Michigan east of MKE into far SW Lower Michigan.

We'll see where this goes in the next 60-90 minutes...

 

[Andrew Khan]

This just in:
THE NATIONAL WEATHER SERVICE IN NORTHERN INDIANA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
BLACKFORD COUNTY IN INDIANA
SOUTHEASTERN GRANT COUNTY IN INDIANA

* UNTIL 945 PM EST

* AT 833 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL. THIS
SEVERE STORM WAS LOCATED NEAR JONESBORO...OR ABOUT 3 MILES SOUTH OF
MARION...AND MOVING EAST AT 25 MPH.

Good guess on the hail size, Andrew.

Thank you, Mark!


There is an area of very well defined low level rotation, in the west side of the Grant County Cell, it looks pretty strong, with a 2.4 nm radius, this seems to be a moderate place for tornado development to occur, it's very obvious on the SRV. A TVS has just been tripped as well, in the near vicinity to this rotation, it's almost in the heart of the storm.