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fxus65 kpub 211029 
afdpub 


Area forecast discussion 
National Weather Service Pueblo Colorado 
329 am MST Sat Nov 21 2009 


Short term... 


(today and tonight) 


Currently...longwave trough was moving onshore across the West Coast 
this morning...increasing SW flow aloft across the 4 corners as well 
as bringing middle and high level cloudiness into western Colorado. As 
of 3 am...temperatures have dropped into the teens for the higher 
elevations and valleys...while the lower areas have cooled into the 
20s to lower 30s. Surface winds remain light in decoupled areas...but 
some of the higher spots are reporting SW winds 15-20 miles per hour with gusts 
to 30 miles per hour. 


Today and tonight...first round of the upper trough axis rolls across 
the state today and tonight...bringing increased cloud cover for 
much of the area as well as some isolated showers to the higher 
elevations of the central mts...northern sangres and Rampart Range. 
The brunt of this upper feature is staying to the north...so trimmed 
areal coverage and probability of precipitation for the possible precipitation...as well as making 
sure onset of precipitation is not until the evening. As for temperatures...leaned 
towards the cooler end of the range for maximum temperatures which favored the 
GFS due to increased cloud cover and weak surface cold front later this 
afternoon...then flipped and stayed a touch warmer tonight due to 
expected brisk winds keeping things well-mixed. Moore 


Long term... 


(sun-fri) 


..main concern is Sunday night/Monday system... 


Main concern during this period is shortwave coming across the 
region Sunday night and Monday. Although all simulations have come 
in stronger with this feature...best upward lower level forcing will 
be north and east of the forecast area. Likewise...I do not see any 
reason to change the precipitation chances over the area...especially the 
plains. 


Main impact this system will have on the plains will be much cooler 
weather for Monday. It will also be quite breezy and the wind combined 
with the cold temperatures will make for an uncomfortable day across the 
area. If precipitation does fall on the plains it will be in the form of 
snow showers with strong vorticity lobe moving across during the Monday 
morning time period. The best chance for any precipitation will be north of 
Highway US 50. 


The main impact with this system will be over the c mountains as has 
been discussed the last several days...this system will have the 
potential to bring several inches of wind driven snow to the high 
terrain. Best chance of accumulate snows will be Sunday night into Monday 
morning on north and west facing slopes. Snow Advisory highlights 
for S/bs may be needed during the aforementioned period. 


Otherwise...trough coming across tonight will cause sundays high temperatures 
to be about 4 to 8f cooler than todays (sat) high temperatures. 


Looking farther out...with the Monday system being a bit stronger 
and slower...temperatures on Tuesday will likely be a bit cooler and have 
tweaked the highs down a few degrees on this day. 


Another system will move to the north and east of the region Wednesday 
night. Although simulations in agreement with the system...GFS is a 
bit farther west and stronger...while ec much farther to the east. 
For now will lean more towards consensus with other weather offices and 
lean towards the ec guidance. Even if the GFS does verify...the 
primary sensible weather concerns Thanksgiving would be some morning low 
clouds and cooler temperatures. \/Hodanish 


&& 


Aviation... 


VFR conditions are expected at the three main taf sites...kcos... 
kpub and kals...through the next 24 hours. 


&& 


Pub watches/warnings/advisories... 
none. 
&& 


$$ 


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