772
FXUS66 KPDT 092343
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
443 PM PDT Thu Oct 9 2025

Updated Aviation Discussion

.DISCUSSION...Current radar and satellite imagery shows high
clouds developing along the WA/OR Cascades with few cumulus clouds
over Central OR. With a stationary low pressure system near the
PacNW coast, this will influence the upslope flow to continue
light showers across the WA/OR Cascades through tonight (15-30%
chance). Winds will be relatively light with occasional breezes as
well. However, tomorrow is when the upper level trough gradually
makes its way across our forecast area with a frontal system.
Showers will then develop over the WA/OR Cascades first before
becoming widespread tomorrow late afternoon into evening hours.
NBM-CONUS favor a 30-60% probability for the Cascades, Central OR,
and North Central to receive wetting rain amounts (0.10-0.15"),
but a 20-40% prob for 0.20" or more. The lower elevations will
most likely have less than 0.10" (>40% chance). By Saturday, we
will start seeing widespread showers as the trough sweeps through
the forecast area. Given the trough`s arrival strengthening the
surface pressure gradients, this may cause an uptick in the wind
gusts up to 40-50 mph for the Gorge and Simcoe Highlands during
Saturday night into Sunday early morning, which warranted an Wind
Advisory for that timeframe. Starting later Sunday morning, gusty
winds will then decrease to 30 mph before becoming breezy (15-25
mph) by afternoon.

In addition to the ongoing troughing pattern, there is also a
potential chance (30-40%) for the Upper Slopes of Eastern WA
Cascades and portion of Kittitas Valley to see snow up to 3 ft this
weekend through Monday with snow levels dropping to 4000-4500ft.
With these conditions not meeting the criteria, we will hold off on
issue an Winter Weather Advisory at this time, but will continue to
monitor. Another round of widespread showers will persist Monday
morning but with the lower elevations becoming dry into next week.
However, showers may linger over the OR Cascades, Central OR, and
eastern mountains with a slight chance (<30%). Winds will be slightly
breezy Monday across the Cascade gaps, but becomes light Tuesday
onward. Feaster/97

.AVIATION...00Z TAFs...VFR conditions to prevail through the
period. Rain chances will increase across western TAF sites after
18Z, with increasing chances after 00Z at eastern sites. For now,
have included prob30s at sites DLS/RDM, with prevailing at site
BDN. Winds will be light through tonight, but will increase to
12-15 kts with gusts up to 25kts at or after 18Z at most sites
except ALW where winds will continue to be 12kts or less.
Lawhorn/82

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  47  72  43  61 /  20  10  40  50
ALW  50  73  47  61 /  20  20  40  60
PSC  45  74  44  64 /  10  10  20  30
YKM  50  72  41  63 /  10  30  20  40
HRI  45  72  44  63 /  10  10  30  30
ELN  45  68  39  58 /  10  40  40  40
RDM  40  64  31  54 /  10  60  70  50
LGD  47  77  41  58 /  10  10  30  60
GCD  46  72  39  57 /  10  10  30  40
DLS  51  67  47  62 /  20  50  60  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory from 11 PM Saturday to 5 AM PDT Sunday for ORZ041.

WA...Wind Advisory from 11 PM Saturday to 5 AM PDT Sunday for WAZ024-
     521.

&&

$$

DISCUSSION...97
AVIATION...82