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Area forecast discussion 
National Weather Service Spokane Washington
849 PM PDT Tuesday Oct 21 2014

Synopsis...
a cold front exits to east this evening, leaving only some isolated
showers in the Idaho Panhandle. From late Tuesday night through
Wednesday night, the next frontal wave and round of precipitation
comes through. The active pattern continues into early next week,
with the potential for more widespread rain late Friday into
Saturday, then again late Monday into next Tuesday, as moisture
associated with former typhoons makes its way toward the Pacific
northwest.



&&

Discussion...
the upper trough axis has moved off to the east and the air mass
has become more stable as warmer air is advected in the mid
levels. The isolated showers that lingered over the Idaho
Panhandle have pretty much ended this evening. The main area of
precipitation associated with the next very moist frontal system
is just starting to move ashore. This frontal band will slowly
move east tonight, reaching the Cascade crest in the next couple
of hours. Models are still showing a southwest-northeast gradient
in quantitative precipitation forecast overnight with the Spokane area right on the edge. Low
level winds have already backed to the south, so it looks like the
basin should escape the rain shadow with this system, but
downsloping off the Camas Prairie and NE blue mts should keep much
of the southeast corner dry until late Wednesday. Some minor
adjustments were made for this update but for the most part, the
current forecast package is on track. /Kelch

&&

Aviation...
00z tafs: low level flow will back to out of the southeast
overnight as a moist Pacific storm system approaches the region.
Strong warm air advection should clear out the low clouds tonight
with rainfall forming northwest of a line from kmwh to kcqv by
Wednesday morning. Keat will likely see light rain developing
after 12z with cigs lowering to MVFR category. Light rain will
spread east to kmwh around 16z, then to remaining taf sites after
20z. Low level wind shear will become a concern as well with
winds increasing significantly off the surface and veering to out
of the southwest, however, low level wind shear is not mentioned
in the tafs as it does not look to be strong enough. /Ek



&&

Preliminary point temps/pops...
Spokane 43 59 48 59 43 56 / 10 60 90 50 20 40
Coeur D'Alene 40 57 45 58 41 55 / 10 40 90 70 30 40
Pullman 43 62 47 59 45 58 / 0 20 70 60 30 50
Lewiston 44 66 51 63 48 61 / 0 10 30 60 40 60
Colville 44 54 46 57 41 56 / 20 100 100 60 20 20
Sandpoint 40 55 43 55 38 55 / 10 60 90 70 40 20
Kellogg 38 57 45 54 41 53 / 10 10 80 80 60 40
Moses Lake 49 59 48 64 43 58 / 20 90 90 20 10 50
Wenatchee 48 55 48 61 44 55 / 70 100 80 30 10 60
Omak 46 52 45 59 40 55 / 80 100 100 40 10 20

&&

Otx watches/warnings/advisories...
Idaho...none.
Washington...none.
&&

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