7/24/09 NOW: MN/IA/WI/IL

[cstrunk]

Severe thunderstorm watch for a large part of Iowa and extreme southeastern Minnesota and extreme southwest Wisconsin.

A new tornado watch has also just been issued for most of eastern Iowa. There is currently an intense elevated supercell in northeast Iowa heading south. SPC mentions favorable conditions ahead of this storm could lead to surface-based development and a few tornadoes.

Waiting for other storms to fire farther west this afternoon.

 

[cstrunk]

Tornado warning for southern Clayton county in northeast Iowa on the supercell mentioned in my last post. Pretty strong rotation evident on radar.

 

[Daniel Christianson]

Correct me if im wrong but it looks like the CF is moving to the SE right now on the Neb side its between columbus and norfolk, if that is what showing up on radar. Im sitting here in Omaha NE waiting for something to go if it can. I feel for those in IA still waiting too.

 

[Scott Lincoln]

Looks like the cap is still holding for now. I think the supercell in northeast Iowa from earlier must have been just along the right side of the cap. I have been watching the steady decline in LFCs over the last few hours just ahead of the cold front in northern Iowa and it has be intrigued for the possibility of more development. It looked like convective temps implied from the special DVN sounding would be in the upper 80s across Iowa.

 

[John Farley]

There have been recent reports of baseball to softball sized hail south of Ossian near the Winnesheik-Fayette County line in northeast Iowa. Also numerous reports the past couple hours of quarter to golfball hail driven by 50+ mph wind in far NE IA and SW WI. Multiple storms are passing over the same areas, so damage and flooding could be quite significant in far northeast Iowa and southwest Wisconsin, and now starting to get into extreme northwest Illinois also.

 

[Ben McMillan]

We are on the Grundy Co. -Hardin Co. line watching a nice tower beginning to anvil. We might break the lid on this one yet. We'll see...

 

[Ryan Wichman]

Based on radar reflectivity....it appears that the MCS in northern IL/IA appears to be at the tail end of the mature stage and entering the decaying stage. Even though the storms still look impressive, I would expect a quick decrease in intensity over the next few hours (especially over the east half of the line) With the loss of heating, storms will quickly become even more elevated as well limiting the threat to hail and wind only.