Carlton, Washington Weather Forecast Discussion

816
FXUS66 KOTX 270534
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
1034 PM PDT Fri Sep 26 2025
.KEY MESSAGES...
- Warm and dry weekend.
- Areas of haze and smoke impacting air quality across the
  region.
- Unsettled weather pattern next week with chances for showers.
&&
.SYNOPSIS...
Temperatures trend warmer for this weekend with highs in the
upper 70s to mid 80s by Sunday. Cooler temperatures and chances
for showers for the first half of next week.
&&
.DISCUSSION...
Friday night through Sunday afternoon: The Inland Northwest will
remain on the western flank of an amplifying ridge centered over the
central US, supported by an active pattern over the Gulf of Alaska.
Moisture streaming in with a frontal system moving into British
Columbia will bring increasing mid and high clouds tonight. Over the
weekend, an upper-level trough approaches the Pacific Northwest
coast as a deep low digs southeast across the Gulf of Alaska. This
will amplify the downstream ridge and allow for a warming trend,
with highs climbing into the upper 70s to mid 80s by Sunday.
Sunday night through Thursday: Ensemble guidance remains consistent
that the leading upper-level trough will move onshore Monday,
followed by a series of systems influencing the Pacific Northwest
through midweek. While there is high confidence in a cooler, wetter
trend, forecast uncertainty persists regarding the exact track and
strength of individual waves. Deterministic models now suggest a
shortwave rounding the southern edge of the Gulf of Alaska low and
pushing inland Tuesday, while the parent low becomes nearly
stationary off the Washington coast by Wednesday.
The initial wave late Monday will favor a showery pattern:
probabilities of >0.10 inches of rain are 50-60% for the mountains,
30-40% for the northern valleys, Spokane area, Palouse, and L-C
Valley, and around 15% in the Columbia Basin. Marginal instability
(MUCAPE around 100-200 J/kg) over the Cascades and the central
Panhandle mountains on Monday will bring a 15% chance of embedded
thunderstorms.  Precipitation chances increase Tuesday into
Wednesday with probabilities for >0.10 inches rising to 80% in the
mountains, 5060% for the valleys, Spokane, Palouse, and L-C Valley,
and 30% in the Columbia Basin. There is also a 15-20% chance for
thunderstorms across far southeast Washington and the central and
southern Idaho Panhandle Tuesday afternoon. Snow levels are expected
to lower to 6500-7000 ft in the overnight periods, supporting light
snow across the higher Cascade peaks.
Late week into next weekend: Forecast confidence decreases for the
late week into next weekend About 60% of global ensemble members
favor a return to upper-level ridging with drier and warmer
conditions, while the remaining 40% maintain an unsettled pattern
with additional shortwaves moving into the Pacific Northwest.
/vmt
&&
.AVIATION...
06Z TAFS: High pressure will build over the Inland Northwest
this weekend. This will allow for VFR conditions to continue
through the period, though smoke will be the primary concern
with winds trending lighter lowering mixing heights.
Fires in the Cascades are very active and will continue to
produce heavy smoke downstream. The smoke is mainly impacting
Wenatchee to Chelan and a subtle shift toward south to
southeastern transport winds will begin to transport smoke
northward toward Omak and into the Cascade valleys. Pullman
is also being impacted from smoke/haze from numerous ag burns
upstream in the foothills of the Blue Mountains. Winds shifting
to the east overnight will favor improving conditions.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
High confidence for smoke to continue impacting KEAT and to a
lesser degree KMWH/KEPH. Scenarios for improvement at KEAT come
with low to moderate confidence and dependent how robust the
southeast transport winds are within the boundary layer Saturday
afternoon. Moderate to high confidence for most other sites to
remain VFR with areas of haze and high level smoke producing vis
between 6-10SM. /sb
-----------------------
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:/weather.gov/otx/avndashboard
&&
.Preliminary Point Temps/PoPs...
Spokane        46  77  50  81  54  74 /   0   0   0   0  10  20
Coeur d`Alene  45  77  51  82  54  75 /   0   0   0   0  10  30
Pullman        43  77  49  81  52  72 /   0   0   0   0  10  30
Lewiston       49  82  55  85  60  78 /   0   0   0   0  10  30
Colville       37  72  37  78  43  72 /   0  10   0   0  10  40
Sandpoint      40  72  45  78  49  72 /   0  10   0   0  10  40
Kellogg        48  77  55  83  59  73 /   0   0   0   0  10  50
Moses Lake     46  77  47  80  52  74 /   0   0   0   0  10  20
Wenatchee      55  76  55  78  59  72 /   0   0   0   0  10  40
Omak           50  76  49  80  54  73 /  10   0   0   0  10  30
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Air Quality Alert until noon PDT Sunday for Central Chelan
     County-Okanogan Valley-Waterville Plateau-Wenatchee Area-
     Western Chelan County.
ID...None.
&&
$$

NWS OTX Office Area Forecast Discussion