Hayden, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

544
FXUS66 KOTX 131037
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
337 AM PDT Wed Aug 13 2025

.KEY MESSAGES...

- Critical fire weather conditions Wednesday due to windy and
  dry conditions

- Cooling trend Thursday through end of week with showers for
  the weekend.

&&

.SYNOPSIS...
A cold front passage on Wednesday will bring windy conditions
across the Inland Northwest. Low relative humidity with gusty
winds will result in critical fire weather conditions across
much of eastern Washington. Showers are expected to return for
the weekend along with cooler temperatures.

&&

.DISCUSSION...
Wednesday: A shortwave, evident on water vapor satellite imagery
this evening, is approaching the northwest coast as an upper-level
trough slides south over British Columbia. This shortwave will
deliver a stronger push of onshore flow and cooler air into western
Washington on Wednesday, increasing the thermal and pressure
gradients across the Cascades. Deterministic models indicate a +9 to
+12 mb sea level pressure difference between PDX and GEG by
Wednesday afternoon. Winds will increase across much of the region
by morning, peaking in the afternoon with the greatest boundary
layer mixing.

Nearly all moisture associated with this system will be wrung out
over the Cascades, leaving dry conditions east of the crest. While
temperatures will cool slightly from Tuesday, highs will still warm
into the 90s with continued low relative humidity across the Inland
Northwest. Afternoon relative humidity values in the teens to low
20s, combined with stronger winds, will create critical fire weather
conditions for much of the region. The strongest winds are expected
in the lee of the Cascades, through the Waterville Plateau, Upper
Columbia Basin, West Plains, and Snake River area, where the NBM
shows a 90% chance of sustained winds exceeding 25 mph. A Red Flag
Warning is in effect from noon to 9 PM Wednesday. Any new fires will
spread rapidly. Use extreme caution with any activities that could
produce sparks.

Thursday through Monday: A transition to a cooler, showery pattern
is expected late in the week as a deep upper-level low develops over
the Gulf of Alaska and digs southeastward. Models are in good
agreement for a cold front, enhanced by an unseasonably juicy
moisture plume (PWATs >200% of normal), to move onshore Friday, then
spread into eastern Washington and north Idaho Friday night into
Saturday morning.

The best rainfall potential will be over the Cascades, far northeast
Washington, and north Idaho, where there is a >70% probability of at
least 0.10 inches of rain. Along the Canadian border in far
northeast Washington and north Idaho, there is a 35% chance of
exceeding one inch. For the Spokane and Coeur dAlene areas,
probabilities are around 50% for at least 0.10 inches. Areas in the
lee of the Cascades, the lower Columbia Basin, and the Palouse have
a 20-40% chance of at least 0.10 inches. Some instability may
support embedded convection, which could produce localized heavier
amounts beneath stronger cores.

Uncertainty remains regarding how long the showery pattern will
persist, with some models keeping showers over the Inland Northwest
into Sunday depending on the exact location of shortwaves rotating
around the base of the offshore low. Temperatures will trend warmer
early next week as troughing lingers over the northeastern Pacific
and an upper-level ridge builds over the southwest. /vmt

&&

.AVIATION...
12Z TAFS: VFR conditions will prevail. A cold front will sweep
across on Wednesday. Westerly winds will increase across the
Inland Northwest through Wednesday morning and become gusty into
the afternoon. Widespread wind gusts of 25-30 kts will be
common across the exposed areas of the Columbia Basin impacting
all airports, including from Wenatchee (EAT) to Spokane/Coeur
d`Alene (GEG/SFF/COE) to Pullman/Lewiston (PUW/LWS).

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
High confidence for VFR conditions. JW

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

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

&&

.FIRE WEATHER...
A Red Flag Warning is in effect from noon Wednesday
through 9 PM for much of the Inland Northwest due to the combination
of strong sustained winds and relative humidity values in the upper
teens to low 20s. While the onshore push of marine air looks to
marginally increase relative humidity values into the 20-25% range
for the lee of the Cascades, sustained winds 25-35 mph would
overcome the marginal relative humidity values if a new fire
ignites. The highest confidence for relative humidity values in the
teens and sustained winds over 20 mph will be for Fire Weather Zone
708 and the eastern portion of Fire Weather Zone 709 where the NBM
indicates a 70-90% chance of these conditions occurring.
Additionally, the Hot, Dry, Windy Index is painting these areas,
including Fire Weather Zones 706 and 707, with a 90+ percent chance
to exceed its 95th percentile. Any new fires that ignite tomorrow
will have a high potential to rapidly spread under these conditions.
Use caution with any ignition sources.

&&

.Preliminary Point Temps/PoPs...
Spokane        92  59  83  59  79  61 /   0   0   0   0  10  30
Coeur d`Alene  93  60  83  58  78  62 /   0   0   0   0  10  30
Pullman        89  55  79  53  78  57 /   0   0   0   0  10  20
Lewiston       99  65  89  63  87  67 /   0   0   0   0  10  10
Colville       92  51  84  51  74  51 /   0   0   0   0  30  60
Sandpoint      90  55  82  54  74  58 /   0   0   0   0  20  40
Kellogg        88  60  79  58  76  62 /   0   0   0   0  10  20
Moses Lake     94  59  86  61  83  61 /   0   0   0   0  10  30
Wenatchee      91  64  86  67  80  66 /   0   0   0  10  40  60
Omak           95  60  88  62  79  62 /   0   0   0  10  30  60

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Red Flag Warning from noon today to 9 PM PDT this evening for
     Colville Reservation (Zone 702)-Eastern Columbia Basin  -
     Palouse  -Spokane Area (Zone 708)-Foothills of Central
     Washington Cascades (Zone 705)-Foothills of Northeast
     Washington (Zone 701)-Lower Palouse  -Snake River (Zone
     709)-Methow Valley (Zone 704)-Okanogan Valley (Zone 703)-
     Waterville Plateau (Zone 706)-Western Columbia Basin
     (Zone 707).

ID...None.

&&

$$