Area Forecast Discussion
Issued by NWS Pendleton, OR

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326
FXUS66 KPDT 281709
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
909 AM PST Fri Nov 28 2025

.UPDATED AVIATION...18Z TAFs...VIS of 5SM at DLS will continue
through 00Z, CIGs at PDT of 900ft will continue through 21Z before
lifting 15kft and ALW will continue to see 200ft CIGs through 22Z.
Otherwise, VFR conditions will continue at the remaining TAF sites
through the period. Winds will remain light below 5kts with the
exception of PSC/BDN seeing 10-11kts. 90


&&

.PREV DISCUSSION... /issued 421 AM PST Fri Nov 28 2025/

DISCUSSION...Widespread precipitation has enveloped the forecast
area as an upper-level trough moves over the region. While
the lower elevations have predominantly observed a cold rain,
snow levels have dropped to 2-3 kft MSL in Washington with
noteworthy snowfall across White and Snoqualmie passes. Though
SNOTEL data suggest we are approaching low-end advisory amounts
for the Washington Cascades, the bulk of the precipitation will
taper off into the early morning hours, so have opted to forgo any
winter weather headlines at this point. Elsewhere, snow levels
are lowering in the Blue Mountains, and are expected to reach pass
levels of 3.5-5 kft MSL through morning. Rain will transition to
a rain/snow mix then snow prior to precipitation ending late
morning through early afternoon. No winter weather headlines are
in effect since snowfall is unlikely to hit our advisory
threshold of 6 inches (10 percent chance per NBM guidance).

Northwest flow aloft will usher in colder air as we head into the
weekend, and ensemble guidance is in reasonably good agreement
that a shortwave trough will pass over the forecast area late
Saturday into Sunday morning. While this pattern favors snowfall,
even for the lowlands, moisture accompanying the system is
lacking, so confidence is low (5-25 percent) in observing
measurable snowfall for the lower Columbia Basin, low-medium
(15-40 percent) along the Blue Mountain foothills, and medium
(40-60 percent) for the Blue Mountain basins such as the Grande
Ronde and Wallowa valleys. Of note, NBM probabilities of
advisory-level snowfall are very low (5 percent or less) area-wide.

Drier weather is likely Sunday into Monday, with ensemble NWP then
showing another shortwave trough diving down from the northwest
between late Monday and Wednesday. Confidence in details with this
system is shaky, but this represents another chance of mountain
and lowland snow.


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  44  28  40  25 / 100   0  10  30
ALW  44  31  39  27 / 100   0  10  40
PSC  49  28  41  23 /  80   0  10  20
YKM  49  27  41  22 /  50   0  10  10
HRI  47  29  41  25 /  90   0  10  20
ELN  45  25  38  20 /  20   0  10  10
RDM  49  24  46  23 /  20   0   0  20
LGD  44  26  44  25 /  90   0  10  40
GCD  46  27  48  26 /  70   0   0  30
DLS  50  35  45  33 /  90   0  10  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
&&

$$

SHORT TERM...86
LONG TERM....86
AVIATION...90