5/21/04 NOW: Upper midwest - Great Lakes - High Plains

[Kevin Scharfenberg]

Several areas of severe thunderstorms already going now (noon CDT) along the front from MI/IN back to IA/MN. More likely to follow later this afternoon from central SD - western NE - western KS - TX/OK panhandles - southeast NM.

Discuss today's developments here...

 

[David Draun]

I am believing that there could be a repeat of 4/20 today. The conditions are similar with the exceptions of MUCH HIGHER CAPE and A LOT more moisture. Remember, it was cold on that morning in Chicago as well. A combination of the wind shifting from NE to SE with the advancing warm front with increasing SBCAPE was strong enough for low-topped SUPs. I think it could very well happen again today over many of the same areas, except perhaps stronger, affecting a large area, and according to soundings, SUP's will not be low-topped. I'm not a MET yet, so this is just a guess. What do you think?

 

[Mike Hollingshead]

That outflow boundary showing up rather nicely on satellite now from Sioux City straight sw through NE. Cape building south of it. Where along it will be the player though? Area around Kearney is really picking up with Cu. Waiting a bit longer here.

 

[David Draun]

The derecho system that hit Chicago this morning has caused a two foot seiche on Lake Michigan. This will cause rises of 2ft on alternating sides of the lake in 1-2hr intervals unitl the seiche has weakened.

 

[Joel Wright]

So far everything is north of the VERY impressive boundary up in northern IA. Softball sized hail was reported in Spencer IA out of a very small but obviously intense elevated supercell. This has since weakened. New elevated cells are firing across north-central IA at this time. Visible immagery shows a fine line of moderate cumulus right on the boundary from IL to NE. South of that it looks really capped right now with only small cumulus patches. There have been a few weak showers trying to form along the boundary just north of DSM, but these seem to be having trouble getting established. At least right now it looks like this is the best area for surface based development.

 

[Joel Wright]

Well the cells north of DSM appear to be growing and getting stronger. The eastermost cell just crossed the boundary and almost looks to have a kidney bean shape to it. This area of central IA looks like it might start to get really interesting...

 

[Mike Hollingshead]

TWC has no risk in eastern 3/4 of NE so I'm going to sit this one out. Seriously though, eastern end of the outflow boundary in ne NE starting to really beef up now.

http://www.rap.ucar.edu/weather/model/disp...rs=hr03hr06hr09

Ruc wants to start hammering nw IA after 21z. Not sure about tornadoes with the sfc flow like it is, but who knows.

 

[Mike Peregrine]

Tor-warning - Grundy County, IA until 2:45 ... and Hamilton Co., Iowa until 2:45.

Mike - you may be further back on the front, but I would still chance it and go after the storms building on the NE/IA line - if they become anything like the ones further east you will be lovin life -

 

[Kevin Scharfenberg]

A small area of very favorable conditions for tornadoes has developed in the Waterloo area, with a pair of supercells. The Grundy county storm has already produced "multiple tornadoes".

Get thee to Waterloo!

 

[Jason Montano]

wish I was in IA right now, but I got a late start and am in Topeka right now, I hope to play some development in E. NE. We shall see.

 

[Ryan Pfannkuch]

Ames, IA chaser Ben McMillan has reported several "large but weak" tornadoes in the Grundy-Black Hawk County area over the past few hours. He has followed the cells from their seemingly innocent initiation in Greene County aroun noon. He cannot confirm damage but a few spotty damage reports are coming in from local media.

 

[mikegeukes]

I will put the links to the LSR's later on, to condensed things.
Nebraska:

NWS North Platte Office: 2 tornadoes in Nebraksa
http://kamala.cod.edu/offs/KLBF/0405220512.nwus53.html

Other Nebraska tornado reports
-------------------------
0835 PM TORNADO 2 N HADAR 42.13N 97.45W
05/21/2004 PIERCE NE TRAINED SPOTTER
-------------------------
0820 PM TORNADO 1 W HADAR 42.11N 97.47W
05/21/2004 PIERCE NE LAW ENFORCEMENT


NWS Davenport Office: 9 Tornadoes in Iowa
http://kamala.cod.edu/offs/KDVN/0405220103.nwus53.html

NWS Des Moines Office: 13 Tornadoes in Iowa
http://kamala.cod.edu/offs/KDSM/0405222241.nwus53.html

Mike

 

[Dan Cook]

Tornado watch issued for Northern Illinois.

I'm heading out soon. Probably towards the De Kalb area.

 

[mikegeukes]

INJURIES

0610 PM TORNADO ROLFE 42.81N 94.53W
05/21/2004 POCAHONTAS IA LAW ENFORCEMENT
THREE TORNADOES. NUMEROUS INJURIES. CONSIDERABLE PROPERTY
DAMAGE.
-------------------------
0623 PM TORNADO BRADGATE 42.80N 94.42W
05/21/2004 HUMBOLDT IA BROADCAST MEDIA
HOMES DAMAGED AND INJURIES.

Mike

 

[John Sickels]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
631 PM CDT FRI MAY 21 2004

AT 627 PM A LARGE TORNADO REMAINED IN THE VICINITY OF BRADGATE.
CONSIDERABLE DAMAGE AND INJURIES HAVE BEEN REPORTED.