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000
FXUS66 KOTX 221558
AFDOTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
858 AM PDT Wed May 22 2013

.SYNOPSIS...
The Inland Northwest will remain under a broad trough through at
least the middle of next week, with disturbances riding in from
the Pacific. This set up means several opportunities for
precipitation. Temperatures are expected to remain cooler than
normal through the end of this week, before some moderation.

&&

.DISCUSSION...
A large closed low near the Tri Cities will continue to produce
wrap around precipitation in the form of rain and mountain snow
today. This morning the heaviest rain will be focused along a
theta e ridge axis over far North Idaho...and in the Wenatchee
area given closest proximity to closed low with low level upslope
flow enhancing precip. Web cameras at Blewett and Stevens Pass
show this precipitation falling as snow this morning but with
roadways wet. This low is expected to migrate north slowly today
with the axis of more persistent rainfall moving north of the
Columbia Basin in the afternoon. However under the cold pool of
-30C at 500mb showers and isolated thunderstorms will develop
behind the main band of stratiform rain around Wenatchee and Moses
Lake. The forecast has been updated to increase precipitation
chances and rainfall amounts for today especially the Okanogan
Valley. Will likely need to evaluate high temperatures today as
forecast values may be slightly too high due to persistent cloud
cover especially near the Cascades, Spokane/Coeur D`Alene area,
and northern valleys. JW

&&

.AVIATION...
12Z TAFS: An upper low pivoting across the Columbia Basin and then
toward western Washington over the next 24 hours will bring bands
of rain to central/eastern WA and northern ID. Coverage is
expected to be best this morning and early afternoon over the
eastern TAF sites, before turning showery in the afternoon. Some
light snow may be mixed in during the morning. The western TAF
sites will also see a modest chance of showers, with the easterly
upslope flow providing the most prolonged threat near KEAT.
Confidence is low with regard to the precise ceilings, but look
for IFR/MVFR cigs over the eastern TAFs much of the morning with
improvement by the afternoon/evening. Confidence is less around
the western TAF sites but the more persistent upslope flow
developing into KEAT may produce lower cigs for a longer period.
Isolated afternoon thunderstorm are possible near the Cascades and
central ID panhandle mtns, generally away from TAFs. /J. Cote`



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        50  36  61  44  62  41 /  90  20  20  10  50  40
Coeur d`Alene  48  35  61  41  61  40 /  90  20  20  20  50  60
Pullman        50  34  61  40  58  40 /  90  20  20  20  60  50
Lewiston       58  39  67  46  65  46 /  90  20  20  20  60  50
Colville       54  36  66  41  69  40 / 100  60  30  20  40  50
Sandpoint      49  35  60  40  62  39 / 100  70  30  20  50  60
Kellogg        46  34  56  42  58  41 /  90  40  30  40  60  60
Moses Lake     59  40  67  45  70  44 /  50  20  30  20  30  20
Wenatchee      55  40  65  45  66  46 / 100  60  40  20  30  20
Omak           56  36  66  41  69  42 / 100  50  40  20  30  50

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Flood Watch through this evening for Northern Panhandle.

WA...Flood Watch through this evening for Northeast Mountains.

&&

$$