Tum Tum, Washington Weather Forecast Discussion

787
FXUS66 KOTX 131122
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
422 AM PDT Sat Sep 13 2025
.KEY MESSAGES...
- Dry and warm Saturday, then cool and showery Sunday into
  Monday.
- Areas of smoke and haze persist through the weekend,
  especially near wildfires.
&&
.SYNOPSIS...
Saturday will be warm and dry across much of the Inland
Northwest with a chance for showers over the central Idaho
Panhandle mountains. The next weather system arrives Sunday
bringing cooler temperatures and chances for widespread
precipitaiton. Areas of smoke and haze are expected to continue
through at least the weekend, especially near wildfires. Warm
temperatures return for Tuesday and Wednesday.
&&
.DISCUSSION...
Saturday: Drier and warmer conditions return to the Inland Northwest
as the upper-level low that brought daily showers exits to the
northeast and a ridge briefly passes through. Aside from a 15-25%
chance of showers and thunderstorms along the Shoshone County,
ID/Montana border, skies will be partly cloudy with widespread highs
in the 80s.
Saturday night through Monday: A cold front and associated upper-
level trough will move onshore across the Pacific Northwest,
bringing increasing cloud cover Saturday night. Model guidance
agrees the front will weaken and the upper-level trough will
elongate as it moves across Washington. This puts eastern Washington
and north Idaho in the northern, weaker portion while the base of
the trough strengthens as it moves across Oregon. Deep southerly
flow and ample moisture (PWATs >0.80 inches) will prime the
atmosphere for rain, but differences in the track of the trough
introduces a high level of uncertainty in the precipitation totals
for the Inland Northwest.
A more southern track into Oregon would keep precipitation confined
to orographically favored areas such as the Cascades, with little to
no rain farther inland. A farther north track across northeast
Oregon would support widespread precipitation Sunday, with lingering
showers over north Idaho Monday. The official forecast currently
favors the wetter scenario with a 40-60% chance for measurable
precipitation (0.01 inches) across much of the Inland Northwest. Far
southeast Washington and the southern Idaho Panhandle/Camas Prairie
are favored a bit more with a 60-75% chance.
For rainfall >0.25 inches between 5 AM Sunday and 5 AM Monday, the
National Blend of Models (NBM) shows:
* Cascades, Camas Prairie, and central ID Panhandle mtns: 60% chance
* Northern mountains, Spokane area, and WA/ID Palouse: 25-40% chance
* Lee of the Cascades and Columbia Basin: 15% chance
Monday night through Thursday: Models are in good agreement for a
return of ridging over the Pacific Northwest, leading to warmer and
drier conditions. Forecast confidence decreases by Wednesday night
into Thursday. While ensembles agree on an upper-level trough
influencing the region, there are significant differences in its
track and strength. This will be the next period to monitor, though
there is too much uncertainty for specifics at this time. /vmt
&&
.AVIATION...
12Z TAFS: VFR conditions will continue through the TAF period.
Chances for showers Saturday afternoon will be primarily across
the ID/MT border with cumulus development across the mountains.
Clouds will increase again Saturday evening ahead of an
approaching cold front. Winds will remain light through the TAF
period.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
High confidence in VFR conditions.
-----------------------
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        84  58  72  53  73  50 /   0   0  40  40  20   0
Coeur d`Alene  84  58  74  53  72  51 /   0   0  40  50  30   0
Pullman        81  53  66  47  68  44 /   0   0  50  60  20   0
Lewiston       87  62  74  57  75  54 /   0   0  60  60  20   0
Colville       84  48  76  45  76  41 /   0   0  40  50  30   0
Sandpoint      81  51  74  50  69  47 /  10   0  40  60  50  10
Kellogg        79  58  72  54  67  51 /  10   0  40  70  50  10
Moses Lake     85  56  72  49  75  48 /   0   0  60  20   0   0
Wenatchee      85  61  73  55  77  56 /   0  10  60  20   0   0
Omak           87  59  77  55  80  53 /   0   0  40  30  10   0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Air Quality Alert until noon PDT Monday for Central Chelan
     County-Northeast Mountains-Okanogan Highlands-Wenatchee
     Area-Western Chelan County.
ID...None.
&&
$$

NWS OTX Office Area Forecast Discussion