178 
fxus65 kcys 301042 
afdcys 


Area forecast discussion 
National Weather Service Cheyenne Wyoming 
442 am MDT Sat Aug 30 2008 


Short term...today through Sunday night... 
another warm and dry today but looks like increasing chances of 
rain by Sunday afternoon. 30/06z surface analysis shows a weak 
high over western Wyoming. Finger of high dew points in Nebraska 
portion of County Warning Area. This feature will probably end up producing some 
stratus early this morning. Satellite showing some hints of black 
stratus near kcys and kimb. Models in good agreement with 
approaching system showing strengthening SW flow aloft as trough 
moves into Pacific northwest. By midday Sunday should start seeing 
some rain in the western County Warning Area but for the most part probably not 
going to see a lot of precipitation make it east of the mountains 
until Monday. Guidance still showing temperatures above normal 
through the weekend. 


Long term...Monday through Friday...sharp upper trough will be 
near western Idaho border at 12z Monday with possible weak upper low 
west of kboi. Models in good agreement lifting the open trough 
northeast through the northern rockies. This will push cold front 
northwest to southeast across County Warning Area during the day Monday. Despite upper dynamics 
going by mainly north of our County Warning Area...there will at least scattered 
showers and thunderstorms mainly Monday afternoon/night. A couple of stronger 
thunderstorms are not out of the question over the southeast third of the County Warning Area 
given degree of instability. Conditions will improve Tuesday morning 
as the system continues moving away into the northern plains states. 
It will be cooler Tuesday and Tuesday night then temperatures will warm a little 
on Wednesday. Dry conditions are expected for the bulk of Tuesday and 
Wednesday. Next system moving down from the north will bring another 
cold front and some showers with it late Thursday into Friday. 


&& 


Aviation...possibly some MVFR ceilings through 30/15z at kcys...kbff 
and ksny. Otherwise VFR next 24 hours. 


&& 


Fire weather...continuing to closely monitor critical fire 
parameters. Once again today areas where the relative humidities 
meet criteria winds will be below criteria and in areas where 
there are stronger winds the relative humidities will not be low 
enough. So will hold off on any watches or warnings at this time. 




&& 


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


&& 


$$ 


Short term/aviation...Griffith 
long term...jlh