872
FXUS66 KPDT 142316
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
416 PM PDT Mon Sep 14 2026

.KEY MESSAGES...
- Weather system will push through the area Tuesday, bringing
  chances of showers and thunderstorms in the mountain areas.

- Chances of isolated thunderstorms greatest on Thursday through
  the afternoon to evening hours.

- Fall like weather continues through the week with high
  temperatures in the low to high 70s.

&&

.DISCUSSION...
Satellite and radar advertise dry conditions with mostly clear
skies across the region. Fall like conditions with highs in the
low 70s to high 70s. Winds are generally light with typical
diurnal winds through the area. Our next weather maker will
arrive sometime Tuesday with a trough/shortwave making its way
down from BC, clipping the PacNW in the process. Flow aloft in
the process will shift to the southwest, allowing for moisture
transportation to bring PoP`s up to 15-40% over Central Oregon
and the mountain region. Most weather will be stratiform with
light to moderate rain showers through the late morning to late
afternoon hours.

Guidance is in good agreement that the low will be cut-off over
Oregon and northern California (80-90% confidence). Chances of
isolated thunderstorms for Central Oregon and mountain regions
increase Thursday (up to 25% chance) with the low overhead.
Wetting rains will remain local, with areas receiving the
heaviest showers/storms receiving wetting rains. Otherwise,
guidance becomes less confidence as we head into Friday after
the shortwave becomes a cutoff low. About 49% of clusters
advertise a drier pattern associated with weaker
trough/shortwave, while the remaining 51% advertise the
opposite. Confidence is better in the latter part of Saturday
and Sunday as most members show at least zonal flow or slight
ridging overhead that has drier weather in place by the weekend.
Although guidance is no where in a conscience how it wants to
handle the shortwave beyond Sunday, although conditions appear
benign until at least the beginning of next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
VFR conditions will prevail through the period at all
terminals. Winds will diminish this evening to be light and
variable for most locations. This will largely persist until
Tuesday afternoon when northerly winds (at around 5 knots)
develop. Some spots in the southwest, such as RDM and BDN, may
see slightly stronger winds in the afternoon, closer to 10 knots
with gusts to around 15-18 knots. Additionally, cloud cover
will increase through the day on Tuesday and there is a low
chance (10-20%) of a few showers over the northwest near YKM.
Confidence is too low to include RA in the TAF at this time, but
this will be reassessed in subsequent updates.

&&

.Preliminary Point Temps/PoPs...
PDT  42  67  45  72 /   0   0  10   0
ALW  47  70  48  75 /   0   0  10   0
PSC  45  70  46  79 /   0   0  10   0
YKM  47  66  48  74 /   0  10  10   0
HRI  44  70  46  76 /   0   0  10   0
ELN  42  61  42  70 /   0  20  10   0
RDM  37  70  39  69 /   0   0  20  10
LGD  41  72  45  74 /   0   0  20   0
GCD  41  75  44  74 /   0   0  30   0
DLS  50  72  54  80 /   0   0  10   0

&&

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

&&

$$

DISCUSSION...95
AVIATION...99/CGAA