Hermiston, Oregon 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

374
FXUS66 KPDT 282252
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
252 PM PST Fri Nov 28 2025

.DISCUSSION...Skies are clearing once again over much of the Basin
as an upper-level trough that brought steady showers and mountain
snow to much of the forecast area early this morning moves out of
the PacNW. NW flow aloft will take its place as we enter a prolonged
period of colder conditions, as ensemble guidance generally locks
the forecast area under a steady synoptic pattern of NW flow with
embedded shortwave activity within. While these shortwaves look to
be relatively moisture-starved, our mountain zones and even lowland
areas could see light snow over the next week as this pattern favors
upslope enhancement of precip even in the absence of an atmosphere
charged with moisture.

Rest of the day looks dry, however low clouds and even patchy fog
may persist and redevelop this evening given recent moisture and
light winds in the forecast. The next best chance for precip (as
part of the aforementioned shortwaves) looks to be late Saturday
evening into Sunday morning. Models aren`t bullish on precip
amounts, so no headlines look to be necessary, however should note
that these NW systems do favor pockets of prolonged snowfall along
the northern Blues and even into the foothills. The HREF in
particular seems to suggest a low-end (30-40%) chance for snow along
the foothills, stretching from Pendleton to Walla Walla. Snow levels
seem borderline, and temps may warm up during the day Saturday, but
the combination of oncoming cloud cover + cold pooling in the Basin
makes me partially skeptical of the NBM snow level forecast. Could
ultimately amount to nothing, but am still wary of stubborn, upslope
snow showers given the pattern. But for the Blues themselves,
expecting only about 1 to 2 inches at best.

The next shortwave looks to arrive around Tuesday. This wave looks
to be a bit more potent based on early NBM QPF readings (at least
for the Blues), but much could change given how progressive the
synoptic pattern is. The key will be where exactly the axis of this
shortwave falls upon arrival. Otherwise, expect cold and generally
cloudy conditions, with highs in the 40s and lows in the 20s across
most areas. 74

&&

.AVIATION...00Z TAFs...Sub-VFR conditions due to low CIGs
are affecting RDM/BDN are sub-MVFR and ALW is sub-VFR and will
continue to remain as such through 14Z for RDM/BDN and 08Z for ALW.
However, there is a 30% chance CIGs could return to sub-MVFR between
05-09Z at RDM/BDN. PDT is sub-VFR but may see a (60-80%) clearing of
CIGs after 01Z only to see sub-VFR conditions return around 14Z.
YKM/PSC are VFR and will remain VFR through the period. Winds are
mostly variable and below 10kts. 90

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  40  26  38 /   0  10  30   0
ALW  31  38  28  37 /   0  10  40  10
PSC  29  41  24  38 /   0  10  20   0
YKM  28  41  23  41 /   0  10  10   0
HRI  29  41  26  39 /   0  10  30   0
ELN  25  38  21  38 /   0  10  10   0
RDM  24  43  25  40 /   0   0  20   0
LGD  27  43  25  40 /   0  10  50   0
GCD  27  48  26  41 /   0   0  40   0
DLS  34  44  34  44 /   0  10  30   0

&&

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

$$

DISCUSSION...74
AVIATION...90