Area Forecast Discussion
Issued by NWS Spokane, WA

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FXUS66 KOTX 041159
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
459 AM PDT Thu Jun 4 2020

.SYNOPSIS...
Today will be another mild and dry day with temperatures in the
70s. Chances for showers will increase Friday as a slow moving
weather system spreads moisture into the Pacific Northwest. The
weekend will be cooler than average with a good chance showers and
breezy at times, especially on Monday. Temperatures will rebound
heading into the middle part of next week.


&&

.DISCUSSION...
Today through Friday night: Another mostly dry air mass can be
expected over region today however there appears to be enough
instability along the Canadian border to bring an afternoon
mountain shower or two in this area but no thunderstorms
expected. Westerly winds aloft continue today with around 15 mph
winds along the central Cascade gaps and Palouse of SE Washington.
With a mix of mostly sun and a few clouds, high Temperatures will
be in the upper 60s and 70s which is just a bit below normal this
time of year.

Later tonight into Friday clouds begin to build in ahead of the
next weather system buckling the flow aloft from a more southwest
to south direction. Clouds increase overnight with mid level
cold frontal band cloud crossing the Cascades in the afternoon.
There are some hints at elevated potential instability ahead of
the front Friday afternoon. Right now there is some potential of
quick moving, isolated thunderstorms from the southeast corner of
WA into the central Idaho Panhandle mountains Friday afternoon to
early evening. These storm`s potential do not look particularly
threatening other than looking out for some isolated lightning if
it occurred. Right now there is alternate guidance that suggests
thunderstorm potential is limited. For now we`ll keep a mention in
the forecast.

Precipition potential goes up significantly Friday night and
becomes more widespread even to the Cascades as the frontal band
moisture builds and deepens in eastern Wa and the Idaho Panhandle.
This will be the beginning of the end of the recently nice run of
weather as cooler and wetter weather will follow into the coming
days. TC

Saturday through Monday: A broad, slow-moving upper level trough
will produce several days of cooler than average temperatures and
periods of wet weather Sat, Sun, and Mon. Despite good chances
for rain over north Idaho and the eastern third of Washington this
weekend, shower chances do not look particularly good for the
East Slopes of the Cascades or the Wenatchee and Moses Lake areas.
The westerly surface pressure gradient is expected to persist from
Friday night through Monday leading to a general downslope flow
for central Washington. At this time, Monday doesn`t look
favorable for rain in Central Washington either given the forecast
track of the upper low pivoting out of eastern Oregon into central
Idaho. The consensus of the medium range models and their
ensembles is for the formation of a deformation band across
western Montana and north Idaho leaving the Wenatchee and Moses
Lake areas dry. Sat and Sun will be breezy as cool air spills over
the Cascades leading to 15 to 20 mph winds across the Columbia
Basin, Palouse, and West Plains. Monday has the potential to be
windier as a surface low deepens over western Montana. Sustained
winds of 20 to 25 mph appear likely across much of the open
farmlands of central and eastern Washington with gusts of 30 mph
or more.

Tuesday and Wednesday: Our slow moving weekend trough will exit
the region Monday night, but another moisture laden frontal system
is forecast to arrive on its heals Tuesday. The progressive nature
of this front will likely lead to the best precipitation chances
of precipitation over the Cascades and the mountainous terrain of
north Idaho. Central and eastern Washington generally don`t get
much measurable precipitation with this type of pattern this late
in the season. /GKoch

&&

.AVIATION...
12Z TAFS: VFR conditions are expected for the 24 hour TAF period.
Dry air moving into the region will help thin clouds in northeast
WA and the north ID Panhandle however showers will occur today in
that area especially in higher terrain. Afternoon winds are
expected to be breezy from southwest in the KGEG KSFF KCOE KPUW
locations and a bit more westerly to northwesterly for KEAT
respectively and a bit more gusty. After 06Z tonight, middle to
high level clouds generally above 10KFT will begin to move in
ahead of the next weather system anticipated on Friday. /TC


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        71  47  75  51  64  44 /   0   0  10  70  60  20
Coeur d`Alene  70  47  76  52  61  44 /   0   0  10  70  70  30
Pullman        68  47  75  49  59  43 /   0   0  10  70  70  20
Lewiston       75  53  81  56  65  50 /   0   0  10  70  70  30
Colville       74  47  74  51  67  44 /  10   0  10  70  80  40
Sandpoint      70  48  74  53  61  46 /  20   0  10  80  80  40
Kellogg        66  48  76  52  59  45 /  10   0  20  80  90  40
Moses Lake     78  51  79  53  73  46 /   0   0  10  30  20  10
Wenatchee      75  53  74  53  69  48 /   0   0  10  30  10  10
Omak           75  51  74  53  69  46 /   0   0  10  50  50  30

&&

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

&&

$$



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