6/23/09 NOW: IA,NE

[jshields]

severe storms have developed over parts of nebraska and iowa under extreme instability along a stationary front/ofb. cape values are progged as high as 7000 j/kg in se nebraska and no cin, with temps in the upper 90's and dews in the upper 70's. there are a couple of severe tstorm watches covering the area. the main limiting factor has been forcing/weak upper level winds, but with extreme instability, large hail and winds over 70 mph have been reported already. recently a tornado warning was issued for waterloo, ia county area for a poss tornado. storms there in eastern iowa have formed into a very healthy squall line with destructive winds over 80 mph possible!

 

[Matthew Piechota]

It is a very nice squall line and hoping it holds together but I have my doubts, upper ridge in place and poor mid-level LR's you would think would cause it to dissipate as it heads east

so far its holding its ground with tons of svr warnings along it and as you said, 70-80mph wind gusts .

 

[jshields]

squall line still holding together in eastern iowa w/ multiple reports of 80mph winds. there's a second smaller squall line that is developing on the back end of the line west of des moines so it looks like des moines could get hit a 2nd time! i hope someone is out "chasing" these storms, i would love to see pics of the shelf clouds with these squall lines!

 

[Ryan Wichman]

Sitting in Macomb, IL....cell in central IL has a sick looking overshooting top and a nice anvil...hmmmmmm

 

[cdpeterson]

Could the mods please add Missouri to the title...

We were eating at the Liberty, Mo Olive Garden when a severe thunderstorm developed right on the town. High winds have been reported at 70 mph with pea sized hail. The Liberty High School campus has numerous large limbs down. At the 1800 block of Liberty Dr. a very large tree was uprooted and is laying on a home with addtional large limbs down around the street and yards. An apartment complex at 200 Belmont has roof damage with trees and limbs down. Widespread power outages and lines down/snapped. Some homes have broken windows. Looks like a downburst?

 

[Michael O'Keeffe]

Very impressive looking cell north of Stapelton, NE in the Sand Hills right now. Looks to have the "debris ball" on it. Spotters have reported a tornado as well.

 

[Gabe Garfield]

Spotters now reporting a "large tornado" near Stapleton, NE. The reflectivity signature is quite impressive, though the velocities -- at least, w/out super-res -- look somewhat unimpressive. Hopefully someone from ST is on it.

Also, it's interesting to note that the tornadic thunderstorm is in an environment characterized by very weak deep-layer shear (<30 kts), if the RUC analysis is to believed. However, there is significant low-level shear where the tornadic thunderstorm is located. Appears to be "riding" some sort of boundary. Right now, it looks as though the storm is transitioning to an HP supercell, so I would expect the tornado threat to diminish somewhat after the current low-level mesocyclone given the weak ambient shear.

 

[Eric Treece]

I am just south of Arnold, NE. Awesome structure on this storm, but very heavy precip core.