980 
fxus63 karx 220330 
afdarx 


Area forecast discussion 
National Weather Service La Crosse WI 
930 PM CST Friday Nov 21 2008 


Update... 
compact closed middle level low pressure system very near Aberdeen South Dakota 
per radar mosaics with band of snow out ahead in isentropic ascent 
/280-290k layer/. Also more snow back in cntl South Dakota with main q/g and 
pv advection. Short term guidance wobbles this circulation east 
and then southeast into and across Iowa on Saturday morning. Right 
now forcing is manifested in a gradually lowering layer of 
altostratus west of MS river...before snow breaks out in southwestern Minnesota. 
Appears given 22.00z RUC and WRF that leading band of isentropic 
ascent will be enough forcing to saturate enough to allow some 
light snow to reach the ground west of MS river by sunrise. 
Forcing rapidly wanes into Saturday morning...but feel enough 
still there for many areas to see a period of light snow or 
flurries. Accumulations will be light...hence another update 
coming out by 03z will run with periods of very light snow but 
lowered chances of measurable from I-35 to MS river. This a rather new 
development with 22.00z models so apologize for the double 
forecast update this evening. 


&& 


Arx watches/warnings/advisories... 
WI...none. 
Minnesota...none. 
Iowa...none. 
&& 


$$ 


Binau