Princeton, Idaho Weather Forecast Discussion

137
FXUS66 KOTX 010755
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
1255 AM PDT Wed Oct 1 2025
.KEY MESSAGES...
- Unsettled weather pattern through Thursday with breezy
  south/southwest winds and multiple chances for showers.
- Gusty west to northwest winds Friday afternoon into Friday
  night for Central WA.
- Dry with overnight lows falling near freezing Sunday onward.
&&
.SYNOPSIS...
A cooler and wetter pattern persists through the week with
temperatures near seasonal normals and multiple chances for
showers. Gusty west to northwest winds develop late Friday
into Saturday with winds shifting to the north with time.
Drier conditions expected Sunday into early next week with
chilly overnight lows and areas of frost.
&&
.DISCUSSION...
Wednesday and Thursday will feature seasonal temperatures and
periods of showers and a few weak thunderstorms as low pressure
continues to spin off the coast and send weak disturbances into
the Inland NW. General trends with the offshore low is for it
to fill/weaken and begin to drift to the southeast by Thursday
evening. As this evolution occurs on Thursday, the southwest jet
will also sag south and east. This will remove Central WA from
impulses lifting through on Thursday and shower activity will
become more terrain based; eastern WA and North Idaho will
continue to contend with these disturbances and periodic waves
of showers. Rainfall amounts under the heavier showers will be
in the range of 0.10-0.15". Local areas that are fortunate to
receive a pair of these heavier waves could end up with over a
quarter of an inch. Not so fortunate areas will be less than a
tenth.
Friday - Tuesday: Over the last 24 hours, models have come into
good agreement for high pressure to amplify in the Gulf of AK
and send another shortwave southward through the Inland NW. This
shortwave looks to pinch off and evolve into a closed low
within the vicinity of N California/Nevada while high pressure
flops over into the Pac NW. What will this mean for the Inland
NW? The initial wave will usher a cold front through the region
roughly Friday evening with gusty west to northwest winds which
shift to the northwest/north on Saturday then northeast to east
Sunday into Monday. Speeds look to be strongest Friday evening
into Saturday with a 30% chance for localized wind gusts of
25-30 mph in areas of Central WA. The front will not have much
moisture given its continental origins and despite a 20-30%
chance for showers across the mountains in the NBM, this will
not bring much in the way of rainfall. As a matter of fact, the
main impacts from this system will be dry air with PWAT
anomalies dropping to 50% of normal and surface dewpoints into
the 20s. Once the winds decrease, there will be strong
radiational cooling and chilly overnight temperatures with many
areas dipping into the 30s and colder, sheltered northern
valleys in the 20s. This will be competing with antecedent warm
soil temps still in the 60s so there is uncertainty how cold
temperatures will become but there is an increase chance that
many backyard gardens will be in jeopardy of freezing
temperatures. At this point, Monday and Tuesday morning look to
deliver the best combination of dry air and light winds but
pockets of freezing temperatures are in the forecast for several
mountain valleys sheltered from winds as early as Sunday
morning.
Wednesday into next week: There is little to no evidence how
the pattern will play out with clusters showing just about
every solution from a ridge (warm and dry) to southwest flow
(warmer with precip chances) to another shot of cooler,
continental air coming in from the northwest. Needless to say,
there is very low confidence in the forecast for the end of next
week. /sb
&&
.AVIATION...
06Z TAFS: An occluded front is lifting through E WA and N ID
06-09z bringing bands of convective showers with embedded
thunderstorms. These cells have a history of producing brief
tiny ice pellets and wind gusts to 22 mph. Conditions will clear
out for a few hours behind this front then additional showers
will track southwest to northeast through the region through
tomorrow evening. The heaviest showers will be capable of cigs
near 4k ft AGL for short periods of times.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Moderate to high confidence for showers on and off given a deep
low off the coast and smaller disturbances tracking through the
region. Timing and location of showers through the day and early
evening come with moderate to low confidence and TAF amendments
are likely. of showers VFR conditions through the period. /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        67  47  64  43  67  42 /  30  50  20   0   0   0
Coeur d`Alene  66  48  64  44  66  44 /  30  60  40  10   0   0
Pullman        67  46  63  42  63  41 /  30  60  30  20   0   0
Lewiston       73  54  67  52  69  48 /  20  60  30  30   0   0
Colville       64  35  64  32  66  32 /  40  40  50  10   0  10
Sandpoint      61  42  61  39  65  39 /  60  70  60  10  10  10
Kellogg        64  48  61  46  64  45 /  60  80  60  20  10  10
Moses Lake     67  44  66  40  70  42 /  20  20  10   0   0   0
Wenatchee      66  46  66  46  69  49 /  40  30  10   0   0  10
Omak           68  43  67  41  69  44 /  30  30  10   0   0   0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
WA...None.
ID...None.
&&
$$

NWS OTX Office Area Forecast Discussion