Pendleton, Oregon 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

018
FXUS66 KPDT 072200
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
300 PM PDT Sun Jun 7 2026

.KEY MESSAGES...
- Widespread rain shower chances and isolated thunderstorms
  across the forecast area Monday into Tuesday

- Breezy lower elevations winds develop Tuesday through
  Wednesday

- Increasing potential for drying and warming trend into next
  weekend

&&

.DISCUSSION...
Today: A transient ridge currently traversing the
PacNW has brought dry conditions across the area, with satellite
showing scattered cumulus fields across portions of the
Cascades, Columbia Basin, and eastern mountains. Breezy to
locally breezy conditions (10-25 mph with gusts to around
20-35mph) continue across the lower elevations this afternoon as
a tightened cross-Cascade pressure gradient remains. Dry
conditions and breezy winds will persist through the remainder
today and into early Monday.

Monday through Wednesday: The transient ridge over the region
will push northeast tomorrow as a shortwave trough dives into
the PacNW from the Gulf of Alaska. Rain showers will develop
across the Cascade crest Monday morning as the shortwave pushes
inland, then quickly spread north and east as the trough axis
swings across the region through the remainder of the afternoon
and evening. Weak surface based instability developing across
the eastern OR mountains Monday afternoon will also result in
isolated thunder chances. In the Columbia Basin, breezy winds
will develop with and just ahead of the main line of showers
Monday afternoon and early evening, though any wind gusts look
to remain below 35mph.

Tuesday, shower activity will retreat mostly to the mountain
areas and Blue mountain foothills as northwest flow aloft
develops behind the trough axis exit. Weak instability will
develop across far northeast OR and southeast WA late in the
morning and afternoon Tuesday, resulting isolated thunderstorms
developing. However, thunderstorm activity is expected to
diminish late in the afternoon as the trough lifts into MT and
southern Alberta. Otherwise, breezy to gusty conditions
(15-30mph with gusts up to 40 mph) will develop in the lower
elevations throughout Tuesday. There is a 60-80% chance of
gusts exceeding 45mph in the Kittitas valley, OR Columbia Basin,
OR Blue mountain foothills, across the Horse Heaven Hills, and
areas northeast of Dayton.

By Wednesday, ensemble guidance solutions favor the trough
sliding further east and upper level ridging developing over the
northeast Pacific. As the ridge further develops throughout
Wednesday, shower activity will diminish across much of the
PacNW, and breezy to locally breezy winds will continue across
the lower elevations.

Thursday through Saturday: Ensemble guidance has come into
better agreement since yesterday in the evolution of the upper
level ridge offshore. About 75% ensemble members now favor the
upper ridge amplifying and moving closer offshore the PacNW
Thursday into the weekend. While the upper ridge may not be
fully over the PacNW, the region will come under the influence
of a warming and drying trend through the end of the weekend.
Afternoon temperatures are advertised to warm into the mid to
upper 80s by Saturday, with NBM probabilities showing a 35-50%
chance of hitting 90 degrees across portions of the Columbia
Basin/Gorge, and the Yakima valley. That said, it is worth
noting that the remaining ~25% of ensemble members favor an
upper ridge further offshore, which would allow shortwaves
rounding an upper low in central Canada to clip the PacNW,
producing light rain showers in the WA Cascades, northern Blues,
and Wallowas. Lawhorn/82

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Dry and sunny
conditions prevail through today and overnight. A system
bringing in rain showers and an occasional isolated thunderstorm
will move in late tomorrow morning. Not expecting any chances
for the TAF sites themselves, but light to moderate rain showers
will move in around 17Z for the Central Oregon and DLS sites.
Was less confident that the rest of the sites will see rain
showers before the 00Z TAF period ends, but have put in
PROB30`sat 22Z for PDT, ALW, and PSC. All sites have a slight
chance (5 to 15 percent) of developing temporary MVFR
conditions, that can bring visibilities >6SM and lower cloud
decks below 3000 feet. Heavier showers could bring some breezier
conditions in the outflow of the rain system.

&&

.Preliminary Point Temps/PoPs...
PDT  44  70  48  67 /   0  40  90  70
ALW  48  73  52  67 /   0  20  90  90
PSC  45  74  48  73 /   0  20  70  40
YKM  46  69  47  71 /   0  50  80  10
HRI  45  72  47  71 /   0  30  70  30
ELN  40  64  44  64 /   0  50  90  40
RDM  40  64  43  64 /   0  80  70  10
LGD  40  71  46  63 /   0  20 100 100
GCD  40  69  44  65 /   0  50  90  60
DLS  50  67  52  68 /   0  70  90  50

&&

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

&&

$$

DISCUSSION...82
AVIATION...95