Area Forecast Discussion
Issued by NWS Spokane, WA

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FXUS66 KOTX 230549
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1048 PM PDT TUE APR 22 2014

.SYNOPSIS...
An active and wet spring weather pattern can be expected across
the Inland Northwest. Showery conditions and breezy winds will
continue this evening and return on Wednesday. Some short-lived
valley snow is possible early Wednesday morning. The next Pacific
storm will bring rain on Thursday, with more showery conditions
Friday and into the weekend.


&&

.DISCUSSION...
Evening update: The region is currently under the influence of
a cool upper-level trof with several embedded disturbances. One
midlevel wave and its associated shower activity is about to
depart Nrn ID while a second is crossing onto the WA Coast.
Between these features, skies are clearing. With dewpoints in the
20`s for much of the Basin, East Slopes, and lower ID Panhandle
temperatures will cool rather quickly until clouds spread in from
the west once again. This will support the idea of lowering snow
levels that have been advertised with the last few days. The one
caveat is across far NE WA and Nrn ID Panhandle where showers from
this afternoon/evening have moistened surface dewpoints into the
upper 30`s. While snow levels will still be low, overnight lows
will not be as cold as expected and the sheltered valleys could
likely see patchy fog.

Otherwise...showers will begin crossing the Cascades after
06z (11PM)...cross into the Columbia Basin 10-11z (3-4AM)...and
track toward the WA/ID border 12-14Z (5AM-7AM). Wetbulb zero
heights on the coolest model (NAM) are around 2000-2500 mainly
east of a line from Waterville to Ritzville to Lewiston which
which will bring the potential for light snow showers at locations
like Spokane...Pullman...CDA...Deary...and St Maries. The highest
threat for a quick burst of light snow will focus across
southeastern WA and the lower ID Panhandle mainly south of a line
from Sandpoint to Spokane to Ritzville where the best dynamics
will track. This is supported by recent model trends as well. This
will give locations above 2200` in the Blue Mtns and Palouse the
best chance for up to an inch of snow. As the showers move into
the ID Panhandle shortly after, snow will still be the dominate
p-type above 2200` but the increasing sun angle will lower the
threat for accumulating snow below 3000`. Locations north of Hwy 2
could see very little precipitation from the second wave. /sb

&&

.AVIATION...06z TAFS: An upper-level trof is currently anchored
over the region. There is a break in the precipitation at this
time but clouds/showers will begin crossing the Cascades
btwn 6z-9z...spreading toward the ID/WA border 13-15z. The
heaviest pcpn with this feature looks to focus across SE WA and
the lower ID Panhandle. Snow will be possible down to 2000` but
most accumulations will focus at elevations of 2500-3000` and
higher. Showers will carry the potential for MVFR cigs and any
intense snow shower could brielfy lead to IFR conditions.  Any
snow should have a hard time accumulating on area runways. Snow
levels will rise above all terminals aft 17z with breezy winds and
sct -shra through 23z. A small break arnd 00z will be followed by
lower cigs and incr -ra chances aft 03z as another moist warm
front lifts into the region. /sb


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  51  39  54  39  55 /  10  60  20 100  40  40
Coeur d`Alene  33  50  38  53  38  55 /  10  60  20 100  70  50
Pullman        34  50  41  54  40  54 /  20  60  40 100  40  60
Lewiston       38  56  45  59  45  59 /  20  50  30 100  50  60
Colville       35  57  35  56  37  62 /  20  50  10 100  40  30
Sandpoint      32  49  36  50  38  55 /  60  60  30 100  70  50
Kellogg        33  45  36  50  37  55 /  20  70  40 100  70  70
Moses Lake     39  61  44  65  39  63 /  20  20  50  60  10  20
Wenatchee      42  60  45  63  42  62 /  20  20  60  60  20  20
Omak           37  59  39  59  37  63 /  20  20  20  90  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




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