Weather

115 
fxus63 kdmx 102036 
afddmx 


Area forecast discussion 
National Weather Service Des Moines Iowa 
320 PM CDT Friday Oct 10 2008 


Discussion... 
warm advection underway across central Iowa so tonight will be mild 
with a southerly breeze around 10 miles per hour with some increase in middle/high 
level cloud cover overnight. 


Not much change in the forecast through Saturday night. Continued 
strong warm advection as the low over the Western Plains deepens as 
it lifts northeast. I have been monitoring trends the last couple 
of days noting that 80s were quite possible for Saturday. Had to 
bump temperatures up today for that time period given the amount of warm 
air pushing up and looking at the source region. Models continue 
their flip flop on timing of the first wave pushing into the west on 
Sunday but the general consensus is that the upper level long wave 
will continue to dig on Sunday and not lift bodily out of the S.W. 
US but rather pieces of energy will eject out of the base of the 
trough and move up the mean flow over western Iowa thus bringing once 
again an earlier start to the precipitation. Probability of precipitation were raised in the 
Sunday period to account for this but still in the low chance 
category since model confidence is low. The models are also now 
back to the slower solution of pushing out on Tuesday thus keeping 
chance probability of precipitation in the east through Tuesday night. Locally high quantitative precipitation forecast is 
possible with such a slow moving system and this has been conveyed 
for several days now. Both models dig another upper trough over the 
upper Midwest region on Thursday night but keep it progressive so 
probability of precipitation were added/adjusted for this time period. Not quite as benign 
a period as previously though as the Euro has a series of these 
upper level short waves progressing across the northern plains. 
Question remains...how many of them will dig far enough to affect 
Iowa. 


&& 


Aviation...10/18z 
VFR conditions through period and likely little if any cloud cover. 
Winds should gust in the upper teens to lower 20s through 00z and 
then increase again somewhat after 15z. 


&& 


Dmx watches/warnings/advisories...none. 


&& 


$$ 


Short term/aviation...small 
long term...fab