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fxus66 kotx 120548 
afdotx 


Area forecast discussion 
National Weather Service Spokane Washington 
948 PM PST Thursday Mar 11 2010 


Synopsis... 
cool wet weather will linger across the inland northwest the next 
few days...with significant mountain snows the main weather 
threat. It's not until Saturday night and Sunday that a 
widespread...but brief...drying trend overtakes the region. 
Temperatures will rise to above normal values by Sunday. 




&& 


Discussion... 
update...a complex weather pattern is seen on area satellite. A 
plume of subtropical moisture extends into the Pacific northwest...and 
the warm front around southern Washington is taking advantage of this 
it to bring waves of precipitation to the inland northwest. The first 
wave has begun to slip northeast toward the Washington/ID/BC border... 
with occasional snow still falling around places like Priest Lake. 
A second batch of precipitation is coming into the upper Columbia 
Basin and is already starting to expand. So while there is a 
break in some areas right now...radar imagery shows it will not be 
long break. 


There are signs of the expected warm up from the south and rising 
snow levels. First the next disturbance is off the coast and the 
pivoting subtropic moisture plume indicates a generalized 
increase in the southerly flow. As dew points have risen above 
freezing in many places and the southerly flow will continue 
through tonight...temperatures are expected to dip little (if 
at all) and in some places may rise overnight. Thus most valley 
areas will see rain or a rain/snow mix. The primary valley 
locations that may hold onto all snow are more likely near Priest 
Lake northward...but as the steadier precipitation is expected to 
begin to shift north and west of this area accumulations are 
expected to remain sub-advisory. 


With the precipitation expanding again tonight...snow advisories 
continue for areas above 2500ft over the Cascades and Okanogan 
Highlands. /Jcote 


&& 


Aviation... 
06z tafs...waves of precipitation (mainly valley rain and mountain 
snow) will continue to spread north of a warm front draped over 
southern Washington...affecting especially areas between keat-kgeg...with 
more scattered to isolated threat toward kcoe and south toward 
klws. Expect MVFR/local IFR ceilings in some rain. The band is expected 
to shift north and west as the southerly flow increased into 
Friday...ahead of the cold front...allowing some improvement in 
ceilings. The front passes later Friday...expand precipitation 
chances back east again with ceilings lowering toward MVFR/local IFR 
again...along with breezy conditions. /Jcote 






&& 


Preliminary point temps/pops... 
Spokane 33 53 32 46 28 49 / 60 40 90 20 0 0 
Coeur D'Alene 37 54 35 45 27 50 / 50 30 90 30 0 0 
Pullman 39 57 30 45 29 52 / 20 40 90 30 0 0 
Lewiston 43 60 38 49 33 58 / 20 10 80 30 0 0 
Colville 34 48 32 49 27 54 / 80 90 90 20 0 0 
Sandpoint 34 51 34 44 27 49 / 60 50 90 30 0 0 
Kellogg 37 54 35 42 28 51 / 40 30 90 50 10 0 
Moses Lake 40 56 34 53 29 57 / 50 90 50 10 0 0 
Wenatchee 37 51 32 51 31 53 / 50 80 10 10 0 0 
Omak 37 47 29 48 27 53 / 60 90 20 10 0 0 


&& 


Otx watches/warnings/advisories... 
Idaho...none. 
Washington...Winter Weather Advisory until 10 am PST Friday above 2500 feet 
for the east slopes northern Cascades...Okanogan Highlands. 


&& 


$$