Richland, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

301
FXUS66 KPDT 160520
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
1020 PM PDT Sun Mar 15 2026

.KEY MESSAGES...

- Walla Walla River flooding through Monday morning

- Warming trend through the week

- Rain in the WA Cascades will lead to increased snowmelt

&&

.DISCUSSION...
Upper level ridging will begin to build over the PacNW tonight,
bringing a prolonged period of warming temperatures, WA Cascade
precip, and dry conditions elsewhere.

Tonight, an upper level ridge offshore will begin its transit
towards western CONUS, where it will gradually push east through
Thursday. Accompanying the upper ridge will be a weak to
moderate atmospheric river, that will clip northern and central
WA throughout the week. Ahead of the ridge, a surface warm front
will lift across the PacNW, with the frontal boundary ushering
in snow levels between 8kft to 10kft. Most locations across the
forecast area will see the warm airmass mix to the surface with
little trouble, however warm air will remain aloft across the
sheltered areas of the WA Cascade crest and east slopes. As the
AR impacts the WA Cascades, precipitation will start off as
snow, but will transition into a wintry mix if freezing rain and
snow late this evening as falling precip interacts with the
warm air aloft. By Monday morning, the wintry mix/freezing rain
is expected to transition to rain as warm air begins to mix down
to the surface. A winter weather advisory is in effect for the
Upper east slopes of the WA Cascades between 8PM tonight and 5AM
Monday morning.

Snow levels will remain above 7-8kft through at least Thursday
as the upper ridge continues to move across western CONUS
(confidence 75-90%). This will mean that precipitation along
the WA Cascades will mainly fall as rain through this period.
Combined with impending warming temperatures under the upper
ridge, the increased snowmelt will result in river levels rising
across rivers and streams originating from the WA Cascades. At
this time, none of the rivers/streams are forecast to reach
flood stage, and will remain within action stage. Of note
however, areas of the Yakima River up river from Cle Elum may
see minor flooding impacts due to channel structure change from
flooding in December.

As mentioned earlier, temperatures are expected to warm across
the region as the upper level ridge moves overhead. By Tuesday,
widespread afternoon temperatures in the lower to mid 70s are to
develop across the lower elevations, warming further into the
mid to upper 70s Thursday and Friday. There is a potential for
the region to see afternoon temperatures warm even further into
the 80s this week, with latest NBM guidance indicating a 60-80%
chance of central OR and the John Day Basin reaching 80 degrees
by Wednesday, and a 25-40% chance along the Blue Mountain
Foothills and Columbia Basin on Thursday.

Friday into Saturday, the upper ridge will push into central
CONUS as an upper level low deepens in the northeast Pacific.
Ensemble cluster is in good agreement that weak shortwaves
ejecting from the low will push across the PacNW, bringing a
shot of cooler air and lowering snow levels across the Cascades
and the northern Blues (confidence 55-70%). Each shortwave
passage will bring light rain and snow to the Cascades and
northern Blues Friday into Saturday, with dry conditions
continuing in the lower elevations into next weekend. Lawhorn/82

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
VFR conditions are likely (80-95 percent confidence, varying by
site) through the period.

Precipitation chances are low (20-30 percent) at PDT/ALW/PSC
late morning into mid-afternoon Monday, and have included PROB30
groups for these sites. Elsewhere, confidence in any
precipitation is too low (20 percent or less) to include
mention in the 06Z TAFs.

CIGs have lowered to around 5-8 kft AGL at most sites this
evening, and there is low confidence (20 percent or less) in
MVFR or lower CIGs at all sites. By Monday afternoon,
anticipating clearing skies with just FEW-SCT high cloud for the
remainder of the period.

Sustained winds are forecast to remain mostly light (12 kts or
less) through the period, but will mention medium confidence
(40-60 percent) in gusts of 15-20 kts at RDM/BDN/PSC later Monday
morning and afternoon. 86

&&

.Preliminary Point Temps/PoPs...
PDT  40  66  45  70 /  30  20   0  10
ALW  42  63  49  66 /  40  40  10  20
PSC  40  66  48  71 /  20  20   0  10
YKM  33  63  42  68 /  40  20   0  10
HRI  40  66  46  71 /  20  20   0  10
ELN  31  55  38  60 /  60  30  10  30
RDM  37  71  38  75 /  10  10   0   0
LGD  37  61  42  68 /  70  40  10  10
GCD  37  67  41  71 /  40  10   0   0
DLS  40  68  45  66 /  30  10   0  20

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 5 AM PDT Monday for WAZ522.
OR...None.

&&

$$

DISCUSSION...82
AVIATION...86