283 
fxus65 kbou 211236 aaa 
afdbou 


Area forecast discussion...updated 
National Weather Service Denver Colorado 
530 am MST Friday Nov 21 2008 


Updated aviation discussion 


Short term...current water vapor and q-g analysis shows fast moving 
short wave racing across Wyoming early this morning. All of the 
lift and better moisture associated with this feature will stay to 
the north and east of US. However...winds will be increasing during 
the early morning hours as middle level flow increases and nose of 
upper level jet approaches. The stability profile is not favorable 
for significant mountain wave enhancement...but the brute force of 
the winds is pretty healthy with Cross Mountain top flow near 40 
knots so mountain tops and higher ridges should gust into the 50s 
and 60s. On the plains...low level cold air should prevent 
development of stronger winds except perhaps across the Wyoming 
border area where enough cold advection and destabilization occurs 
to sufficiently mix the higher momentum air down to the surface. At 
this time...Denver area expected to remain in anticyclonic 
east/southeast flow for most of the day. 


High level moisture will gradually increase through the day so 
expect generally partly sunny skies by noon. Temperatures will be 
very close to normal for a change. 


Long term...generally mild and benign weather will continue over 
northern Colorado through this forecast period. An upper ridge 
holding its position over the southwestern U.S. Will keep moisture 
away from the state along with temperatures slightly warmer than 
normal. A transitory short wave moving through the ridge on Sunday 
will cool temperatures slightly on Sunday afternoon. However...no 
precipitation is expected during that period. As the ridge 
re-strengthens early next week...temperatures on the plains may 
reach the 60 degree mark on Tuesday. Some changes appear to be in 
store for late next week as both the GFS and European model (ecmwf) show a troffiness 
over the southwestern U.S. On Thursday and Friday. The two models 
have their differences in timing and shape of the trough...so will 
only mention a slight chance of snow over the mountains...since they 
will be the first locations to be affected by the increasing 
moisture. There is still plenty of time to see how the models 
resolve the impending change in flow pattern. Until then...dry and 
slightly warmer than normal will be the rule. 


&& 


Aviation...the winds have shifted to the northwest at dia and as a 
result...dense fog was spread across the Airport. Expect this to 
last through 16z and then gradually lift toward 18z. Kbjc will also 
have to be watched closely this morning. Otherwise VFR conditions 
will prevail and expect shallow anticyclonic east/southeast upslope 
flow this afternoon/early evening. Depth of anticyclonic flow 
should be deep enough to prevent low level wind shear at the Front 
Range airports. 


&& 


Bou watches/warnings/advisories...none. 


$$ 


Barjenbruch/kdrby