Rathdrum, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

315
FXUS66 KOTX 160519
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1019 PM PDT Sun Mar 15 2026

.KEY MESSAGES...

- Increasing clouds with light mountain snow Sunday night.

- Warmer this week in the lowlands, with occasional but limited
  precipitation chances.

- Rain on snow in the Cascades increases hydrology concerns this
  week.

&&

.SYNOPSIS...
Snow increases around the mountains this evening into early
Monday. Snow and rain chances develop over the lowlands this
evening and overnight too, with a limited accumulation potential
outside the northeast mountain valleys. A warmer, periodically
breezy pattern settles in for much of the work week.
Precipitation, moderate to heavy at times will be possible along
the Northern Cascades with increasing concerns for rises on
rivers. Lighter precipitation with snow melt will lead to
additional rises in the Idaho Panhandle.

&&

.DISCUSSION...
Tonight and Monday: the first in a series of frontal waves that
will usher in milder weather comes in. This evening a warm
front lifts in, followed by a weak cold front overnight into
Monday morning. Tapping into the leading edge of a plume of
moisture, with PWAT rising to 200-300% of normal (or 0.75 to
1"). All this moisture converges best at the Cascade crest and
secondarily over NE WA and the ID Panhandle, with the frontal
wave. These areas will have the best chance of precipitation
this period. The lowlands will see a definite risk for
precipitation (generally between 30-60%, except 10 to 20% in
the deeper basin); but precipitation amounts will be lower.

Precipitation-type: largely the temperatures profile support
snow to begin with over the mountain and northern two-third of
WA and ID, with rain or a rain/snow mix over the southern third
of WA and the lower ID Panhandle. However overnight into Monday
morning snow levels rise and push above most pass levels toward
midday to afternoon. Before then some accumulation is possible.
The Cascade valleys, such as the Methow Valley, are expected to
hold onto the cooler air a bit longer than areas further east
and the NBM forecast was adjusted to keep them lower
tonight/early Monday.

Snow amounts: some moderate snow amounts are forecast for the
Cascade crest, with near snow rates potentially approaching
1"/hour this evening at Stevens Pass, before decreasing
overnight into early Monday as the milder air starts in. Other
light to moderate snow are possible late this evening into early
Monday AM near the Central ID Panhandle, including Lookout
Pass. Winter weather advisories were issued for the Cascade
Crest this evening through early overnight; one was issued for
the Central Panhandle Mountains above 3000 feet for later this
evening to late Monday AM. There are some models showing a
slight chance of freezing rain mixed in near the Cascade valleys
and maybe some of the sheltered central Panhandle valleys, as
the milder air surges in aloft before surface temperatures have
a chance to catch up. Confidence is low, but it is a non-zero
risk. Elsewhere some light snow accumulation is possible over
the northeast WA and north ID valleys too, around 0.5 to 1.5".
Other areas could see trace to 0.5", but confidence leans closer
to a trace to 0.1" if that.

Lows tonight are forecast to be in the mid-20s to mid-30s, with
some upper 30s over the deeper basin and L-C Valley. Highs
Monday are forecast to be in the 40s to lower 50s, with some
mid 50s to mid-60s over the deeper basin and L-C Valley, with
the warmer of those readings in the deeper basin.

Tuesday to Saturday: The regions becomes dominated by a strong
zonal flow and progressive pattern, steeped in the atmospheric
river with PWATs around 175 to 250% of normal. The jet stream
remains largely centered north of the Canadian border until
Saturday when it dips south into our region. Through the week
impulses riding by the area are rather weak, but precipitation
chances will continue. The best chances will be in the Cascades
and Idaho Panhandle Mountain in the orographically-favored lift
in this flow, with PoPs around 60-90%. Away from these areas the
central and eastern third of WA and lower ID will see chances
around 10-50%, with the lowest of that risk in the deeper Basin
and L-C Valley. Regardless of chances, the higher precipitation
amounts are focued in the Cascades and secondarily the ID
Panhandle Mountains.

Here are the latest probabilities for storm total QPF amounts
from Sunday night to Saturday (some of this will be snow
Sunday night and Monday).

Total QPF (Mon-Fri) >1 inch >2 inches >3 inches >5 inches

Cascade Crest100% 90%  80%40%
Idaho Panhandle     50%      10%      0%        0%

Additionally, recent heavy snow may be able to absorb the rain,
but it may begin to ripen and start to runoff, especially with
the mild temperatures and increasing wind which can enhance
snowmelt. We will continue to monitor this. This could cause
some hydrological issues.

Those winds mentioned will be breezy each day, with gusts in the
15-30 mph range. However if any of those shortwaves are a bit
stronger, some locally stronger gusts are possible.

Temperatures are still forecast to trend warmer. Highs in the
50s are forecast for a large portion of the area Tuesday, with
60s in the lee zones, deeper basin and L-C Valley and maybe some
areas near 70 in that deeper basin. Temperature edge warm
Wednesday and by Thursday highs are forecast to be in mid-50s to
mid-60s, with some lower to mid-70s in the deeper basin and L-C
Valley. Temperatures then cool again toward next Saturday with
highs in the upper 40s to 50s, with localized low 60s in the
typically warmer spots. Compared to yesterday the potential for
the Spokane area reaching 70 later this week had declined to
only 10-30%. /Solveig


&&

.AVIATION...
06Z TAFS: VFR conditions will prevail for KEAT-KMWH-KLWS. Areas
of snow this evening will change to rain as warm advection
occurs. There is a 20-50% chance for MVFR ceilings for KGEG-
KPUW-KSFF-KCOE through 21z Monday. Winds will be breezy out of
the southwest gusting around 14-20 kt for KGEG-KSFF Monday
afternoon.

FORECAST
CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate confidence with
terminals dropping to MVFR tonight as snow falls. Lower
confidence in ceilings as snow changes to rain. There may be
some patchy freezing rain mixed in near the Cascade valleys
overnight/early Monday AM, but the risk is low at any terminals.


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

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        32  47  41  56  47  60 /  60  50  20  20  50  20
Coeur d`Alene  31  45  41  53  44  57 /  80  80  40  30  70  30
Pullman        35  51  43  58  45  60 /  60  70  20  30  40  20
Lewiston       40  56  44  65  47  68 /  60  60  10  10  30  10
Colville       28  47  35  58  43  60 /  80  60  20  20  40  30
Sandpoint      30  42  40  51  42  53 /  80  90  50  50  90  50
Kellogg        30  45  43  51  46  54 /  90 100  60  60  80  60
Moses Lake     35  60  44  68  48  67 /  20  10   0  10  10   0
Wenatchee      35  57  43  65  47  62 /  50  30  10  20  30  20
Omak           34  52  39  62  44  63 /  40  20   0  10  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 2 AM PDT Monday for Western
     Chelan County.
ID...Winter Weather Advisory from 8 PM this evening to 11 AM PDT
     Monday for Central Panhandle Mountains.

&&

$$