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fxus66 kotx 211810 
afdotx 


Area forecast discussion 
National Weather Service Spokane Washington 
1010 am PST Sat Nov 21 2009 


Synopsis... 
after a short relatively quiet break in the weather today...a 
stronger and colder storm system will bring the potential for 
moderate to heavy snowfall over much of the region tonight and 
Sunday. A series of storm systems will continue to pass through 
the inland northwest every 24 to 36 hours through at least the 
middle of next week. 




&& 


Discussion... 
quick update this morning to decrease clouds and probability of precipitation across the 
basin and northern valleys. Visible satellite imagery showing 
very little in the way of clouds at this hour and shower activity 
is mainly confined to the higher terrain of the Cascades and Idaho 
Panhandle. Water vapor imagery showing a fast moving storm system 
beginning to take shape out near 135w 45n which will bring our 
next round of wintry weather overnight into Sunday. 






&& 


Aviation... 
a weak ridge aloft will promote VFR conditions at all taf sites 
through 03z tonight...with lingering snow showers locally 
obscuring mountains in the Idaho Panhandle and Cascade crest. 
The next Pacific storm system will spread IFR ceilings to the 
western reaches of the region after 04z...spreading into the 
eastern terminals after 10z. The incoming storm system will 
also tighten pressure gradients leading to increasing winds 
from kpuw-kgeg with gusts of 25-35kts. 






&& 


Preliminary point temps/pops... 
Spokane 39 32 37 27 39 31 / 10 70 90 10 40 10 
Coeur D'Alene 39 31 37 28 40 31 / 20 60 90 20 50 20 
Pullman 40 32 36 28 42 32 / 20 60 90 20 40 20 
Lewiston 47 36 41 30 48 35 / 10 60 90 20 30 20 
Colville 39 33 40 28 38 30 / 10 100 90 10 60 20 
Sandpoint 33 32 37 28 36 30 / 40 90 90 20 60 30 
Kellogg 32 30 34 27 35 30 / 70 70 100 40 60 40 
Moses Lake 45 32 43 26 43 30 / 10 80 50 0 40 10 
Wenatchee 43 32 43 29 41 33 / 10 90 50 10 50 10 
Omak 43 31 42 25 40 27 / 10 100 50 0 60 10 


&& 


Otx watches/warnings/advisories... 
Idaho... Winter Storm Watch from late tonight through Sunday morning for 
Coeur D'Alene area. 


Winter Storm Watch from 6 PM PST this evening through Sunday 
morning for northern Panhandle. 


Winter Storm Watch from this evening through Sunday afternoon 
above 2500 feet for central Panhandle mountains. 


Washington... Winter Storm Watch from late tonight through Sunday morning for 
Spokane area. 


Winter Storm Watch from 6 PM PST this evening through Sunday 
morning for east slopes northern Cascades. 


Winter Storm Watch from 6 PM PST this evening through Sunday 
morning above 2000 feet for northeast mountains...Okanogan 
Highlands. 


Winter Storm Watch from 6 PM PST this evening through Sunday 
morning above 2000 feet for Okanogan Valley...upper 
Columbia Basin...Waterville Plateau. 


&& 


$$