471
FXUS66 KPDT 241033
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
333 AM PDT Fri Apr 24 2026

.KEY MESSAGES...

1. Drier and cooler temperatures through the weekend

2. Freeze Warning for Saturday morning

3. Mountain precipitation returns Sunday

&&

.DISCUSSION...
Current radar shows the returns to have moved out pf the region and
to the southeast. Ground observations show trace amounts of rainfall
occurred since 5 PM. No more precipitation is expected through the
the weekend until the next system moves across the region beginning
Sunday.

Models are in form agreement with the upper level flow for the
northwest. This pattern is brining in drier and cooler air which is
leading to below average seasonal temperatures through the weekend.
In house seasonal calculations show that Friday and Saturday high
temperatures will be between 5 to 10 degrees below seasonal normal
with some isolated 15 degrees below normal along the ridgelines.
Temperatures over the weekend are expected to be in the mid 50s with
some isolated locations in the Basin seeing low 60s with 70-90% of
the NBM raw ensembles in agreement.

Models show the region to be influenced by colder air, coupled with
dry air and clear skies, temperatures are expected to dip into very
cold temperatures across the region. So much so that a freeze
warning has been issued for the Kittitas Valley, lower Columbia
Basin and the foothills of the northern Blue Mountains of OR and WA.
Guidance shows temperatures through the aforementioned areas to be at
or below freezing Saturday morning. 70-90% of the NBM raw ensembles
are in agreement with these cold temperatures. In house seasonal
comparisons show these areas to be 10-15 degrees below seasonal
average.

Models show a shift in the pattern as an upper level low coming out
of B.C. clips the region. This will bring chances of mountain
precipitation Sunday with very little accumulations. By Monday,
precipitation amounts will be more prevalent, especially across the
eastern mountains and OR Cascades Sunday with rain amounts between
0.01-0.02 along the foothills and 0.04-0.07 along the crests with 50-
70% probabilities. Very light mountain showers will persist through
Tuesday before dry and warmer temperatures make it way back into the
region under an incoming upper level ridge. 90

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
VFR conditions will persist through the forecast period. Cigs
will be 25kft to SKC through the period with winds below 12 kts.
90

&&

.Preliminary Point Temps/PoPs...
PDT  55  31  59  34 /   0   0   0   0
ALW  57  35  60  38 /   0   0  10   0
PSC  61  31  64  35 /   0   0   0   0
YKM  61  34  63  36 /   0   0   0   0
HRI  60  31  63  34 /   0   0   0   0
ELN  56  31  58  34 /   0   0   0   0
RDM  57  24  57  27 /   0   0   0   0
LGD  51  28  55  31 /  10   0  10   0
GCD  52  28  55  30 /   0   0  10  10
DLS  63  37  66  39 /   0   0   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
WA...Freeze Warning from midnight tonight to 8 AM PDT Saturday for
     WAZ026-028-029.
OR...Freeze Warning from midnight tonight to 8 AM PDT Saturday for
     ORZ044-507.

&&

$$

DISCUSSION...90
AVIATION...90