Area Forecast Discussion
Issued by NWS Spokane, WA

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376
FXUS66 KOTX 010615
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1015 PM PST Sun Nov 30 2025

.KEY MESSAGES...

- Light snow late Monday into Tuesday, especially in the
  Central Panhandle Mountains.

- Modifying temperatures and a transition of snow to rain late
  this week.

&&

.SYNOPSIS...
A weather system on late Monday into Tuesday will bring light
snow mainly to the Idaho Panhandle and extreme Eastern
Washington. Temperatures will modify and warm above normal late
this week. Unsettled late this week as well with snow
transitioning to rain in the lowlands.

&&

.DISCUSSION...
Tonight: A short wave ridge off the coast will move over the
region tonight for dry conditions. An abundance of stratus today
over Southeast Washington into the south ID Panhandle has been
slowly moving north this afternoon as boundary layer winds shift
out of the south. Continued expansion of stratus northward is
expected through tonight, which should help keep fog coverage
mostly patchy in coverage.

Monday through Tuesday: A wave topping the ridge moves over the
region bringing an increased threat of mainly snow Monday
afternoon into Tuesday as colder temperatures support low snow
levels. Precipitable water values briefly increase to around
150-175% of normal, which combined with isentropic ascent into
the ID Panhandle and eastern third of Washington leads to the
development of light snow. The highest amounts are expected in
the Central Panhandle Mountains and the Camas Prairie where
upslope flow is maximized. The 12z ECMWF ensembles have trended
upward with precipitation totals and snow amounts. Here are the
latest NBM chances for 1" of snow or more: Colville: 20%,
Spokane 15%, Pullman 20%, Sandpoint 60%, Kellogg 60%. Given that
the latest NBM doesn`t have the 12z ECMWF ensembles
incorporated, it`s possible that these numbers increase with the
next run.

Tuesday Night and Wednesday: As this system pushes east, a short
wave ridge moves in for another drier period. A moist boundary
layer combined with the ridge is a good setup for more fog and
stratus over the region.

Thursday through Sunday: An active pattern becomes established
by the weekend as an arctic air mass slides south into Central
British Columbia, while a strong pacific jet also takes aim at
the region. The jet is likely to keep cold air well north of our
area, with 85% of the ensembles favoring an active jet over the
region with an influx of moisture and milder air. The increase
in temperatures and snow levels will result in mainly a valley
rain and mountain snow situation although some valleys may begin
as snow with the initial warm front late Thursday or Friday
before snow levels rise. The strong jet will also bring breezy
to windy conditions on Friday. There is some model spread in the
details that far out regarding exactly how windy. The NBM
currently has a 30% chance of wind gusts exceeding 40 MPH at
Wenatchee and Pullman, and a 15% chance for Spokane. Wenatchee
has a 20% of gusts exceeding 50 MPH as well. Similar
probabilities are forecast for Saturday and Sunday. JW


&&

.AVIATION...
06Z TAFs: Stratus across much of eastern Washington and the
Idaho Panhandle is bringing ceilings down to MVFR for all TAF
sites but KLWS/KMWH/KEAT. The stratus looks to expand northward
over the next few hours. In particular, the NAM indicates that
KEAT may see some MVFR stratus as well around 09Z. Models right
now don`t show TAF sites getting to IFR, but there could be
patchy fog in some areas. A warm front begins passing through
around 18Z, and with it will bring light snow to
KGEG/KSFF/KCOE/KPUW, and rain to KLWS. Much of this
precipitation is anticipated to start around 0Z. There are
smaller (less than 30 percent) probabilities of the
precipitation starting around 18Z.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
There is high confidence that the MVFR stratus will stick around
through much of the forecast period for KGEG/KCOE. There is
somewhat lower confidence in ceilings remaining at MVFR for
KSFF, which looks to improve slightly before the precipitation
moves in. There is low to moderate confidence in stratus moving
through KEAT around 09Z. Biggest uncertainties lie with
precipitation, where there are some signals that it may begin a
bit sooner than 0Z, but these probabilities are currently low.
High confidence in precipitation type for each TAF site. /AS

-----------------------

Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance

For additional probabilistic information for NWS Spokane
airports,please refer to the Aviation Dashboard on our
webpage: https:/www.weather.gov/otx/avndashboard

&&

.Preliminary Point Temps/PoPs...
Spokane        25  32  28  34  24  36 /   0  20  40  20   0   0
Coeur d`Alene  25  33  29  35  27  38 /   0  20  60  40   0   0
Pullman        24  36  29  35  28  38 /   0  20  50  70  10   0
Lewiston       28  38  33  41  33  42 /   0  10  40  60  10   0
Colville       19  32  22  37  19  37 /   0  40  40  10   0   0
Sandpoint      22  32  27  34  25  35 /  10  50  80  40  10  10
Kellogg        25  33  32  35  29  38 /   0  30  70  80  10  10
Moses Lake     24  36  27  38  24  38 /   0  10  20   0   0   0
Wenatchee      29  35  32  39  30  41 /   0  10  20   0   0   0
Omak           25  35  27  39  27  39 /   0  20  20   0   0   0

&&

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

&&

$$