703 
fxus65 kcys 100024 aaa 
afdcys 


Area forecast discussion...updated 
National Weather Service Cheyenne Wyoming 
524 PM MST Friday Jan 9 2009 


Update... 
just a brief early update this evening to indicate the 
cancellation of the Wind Advisory in the western Nebraska 
Panhandle. Winds have decreased in speed early this evening...with 
15 to 25 miles per hour expected through around 700 PM MST before gradually 
decreasing overnight and becoming more westerly at just 5 to 15 
miles per hour by early Saturday morning. 


Numerous locations gusted into the 50 miles per hour range earlier this 
afternoon with sustained winds generally near to slightly stronger 
than 30 miles per hour. 


&& 


Short term...tonight through Sunday... 
there have been a couple of distinct frontal passages over County Warning Area 
today with winds going north-northeast for a few hours and then back to north-northwest 
and increasing again. Small bands of light snow have also been 
occurring over north and west parts of the County Warning Area. Clouds/winds and 
areas of light snow will continue to decrease during the evening. 
Did keep the Wind Advisory for western Nebraska Panhandle until 01z. 
Northwest flow aloft will prevail Saturday through Sunday. This will 
keep some snow showers over the south central Wyoming mountains. 
Clouds will increase elsewhere...especially Sat night and Sunday 
as another shortwave trough sweeps through. Downslope winds will 
be picking up again Sat night. Usual two locations of Arlington 
and Bordeaux may get close to high winds though it looks more 
marginal now on 18z nam12 run...so did not issue watch. Temperatures 
will be near or slightly above normal Sat...then warmer Sunday. 


Long term...Sunday night through Friday... 
fast and energetic northwesterly flow aloft will prevail from Sun 
night through Thursday. Upper flow will decrease in strength Friday but will 
remain northwesterly. Surface based leeside troughing will produce 
brisk winds Sun night...then a cold front will usher in colder 
conditions Monday with a small chance of snow. Temperatures Monday will be 
approximately normal. Leeside troughing will redevelop Monday night 
with adiabatic warming associated with brisk downslope flow 
moderating temperatures somewhat Tuesday. The chance of snow Tuesday will be 
limited to far northern portions of the forecast area in closer 
proximity to deeper moisture. A backdoor type cold front will push 
through Tuesday night and will bring colder temperatures and a chance of light 
snow Wednesday. Thursday will remain rather chilly but looks to be dry as the 
low level upslope weakens and moisture correspondingly decreases. 
Friday will be dry and warmer as low level return flow develops on the 
backside of surface high pressure located over the Southern Plains. 


&& 


Aviation... 
local MVFR ceilings and visibilities in parts of eastern and southern County Warning Area 
early this evening...otherwise VFR conditions will occur tonight 
through Saturday night. 


&& 


Cys watches/warnings/advisories... 
Wyoming...none. 
NE...none. 


&& 


$$ 


Short term/aviation...CArpenter 
long term...Jr