Pendleton, Oregon 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

272
FXUS66 KPDT 162339 AAA
AFDPDT

Area Forecast Discussion...UPDATED AVIATION.
National Weather Service Pendleton OR
439 PM PDT Wed Apr 16 2025

.SHORT TERM...Today through Friday night...

Key Messages:

1. Breezy winds this afternoon and again on Thursday.

2. Dry conditions persist through the week.

3. Cooling temperatures Thursday before warming Friday.

Current radar and visible satellite imagery shows very light
returns along the northern Blue Mountains under mostly clear
skies. This is a result of a weak upper level shortwave that is
dropping through eastern Washington and Oregon from the north this
evening ahead of another shortwave following in its wake on
Thursday. Isobars will tighten with each passing system to provide
widespread breezy winds this evening into the overnight period,
with sustained north-northeast winds of 15-20 mph and gusts of
30-35 mph peaking after 5 PM. Winds are expected to slowly
dissipate around midnight before increasing again late Thursday
morning through Central Oregon, John Day Basin, and the Blue
Mountains and foothills. Winds will begin to subside after 8 PM
Thursday as an upper level ridge moves in from the west-southwest
into Friday.

A dry and cool airmass is associated with these synoptic features,
allowing for high temperatures Thursday to drop 8-12 degrees from
today and peak in the low to mid-60s across the Lower Columbia
Basin, Blue Mountain foothills, Gorge, and Central Oregon.
Limited cloud cover associated with this dry system will bring
down overnight temperatures into the low to mid-30s, with freezing
temperatures expected in Deschutes County. Moderate overnight
humidity recoveries will arrive tonight and linger overnight
Thursday associated with the two passing systems, with afternoon
humidities dropping into the upper-teens to mid 20s from low to
high elevations. North flow aloft on Thursday will slowly turn to
more out of the west into Friday to bump high temperatures back
into the upper 60s to low 70s as a quick ridge slides in the area.
75


.LONG TERM...Saturday through Wednesday...Models are in good
agreement in having a series of weak shortwaves move through the
area during the long term period, but the overall weather looks
benign. The systems are very weak and models indicate almost no
precipitation except along the Washington Cascade crest and even
there the amounts are fairly light. The main impact will be tighter
pressure gradients leading to breezy winds most afternoon, though
nothing that would approach wind advisory levels. Temperatures in
general should be a couple of degrees above normal for mid April.
The Extreme Forecast Index highlights marginally noteworthy winds in
the Eastern Columbia Gorge and western Blue Mountain Foothills and
Oregon Columbia Basin Saturday and Sunday with values around 0.75.
Overall forecast confidence is good then drops off somewhat on
Tuesday and Wednesday as the usual model differences arise.

Saturday will have a weak shortwave cross the area with just a few
hundredths of an inch of QPF along the Washington Cascade crest in
the morning and little anywhere else through the day. Snow levels
are at 4500 feet, so rain is expected at pass level. A slightly
stronger wave arrives Sunday with a chance of rain showers along
both the Washington and Oregon Cascade crest and the eastern
mountains. QPF amounts are barely measurable except along the
Washington Cascade crest again which looks to get less than a tenth
of an inch rain with snow levels around 4000 feet. Each afternoon,
northwest winds of 15 to 25 mph are expected.

Models show additional shortwaves arriving Monday and Tuesday
afternoon, though with little if any precipitation. Winds will be
lighter as well and mainly northwesterly at 10 to 20 mph. Wednesday
shows a transitory ridge over the area ahead of a fairly strong
closed low in the Gulf of Alaska.

Temperatures will be in the upper 50s and 60s Saturday through
Tuesday then warm a few degrees to the mid 60s to lower 70s
Wednesday. The mountains will mainly be in the mid 40s to mid 50s
through the period. Perry/83


&&

.AVIATION...00Z TAFs...VFR conditions area-wide with satellite
showing increasing mid clouds across south central WA and the lower
basin. Northerly flow regime in place after a passing cold front
earlier today and reinforcing northerly flow tonight-tomorrow.
Initial mid clouds we are seeing, bases 9-10 kft, will lessen and
clear out mainly after 06Z. Otherwise, current breezy winds that are
in place will lessen similarly around that timeframe. Winds will
pick up 18Z tomorrow onward though not as gusty at KPSC, KALW, KPDT,
and KDLS terminals. However, gusts more likely than not at central
OR terminals up to 20 kts in the afternoon.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  33  60  34  67 /  10   0   0   0
ALW  35  60  38  66 /   0   0   0   0
PSC  37  65  37  72 /   0   0   0   0
YKM  37  65  38  70 /  10   0   0   0
HRI  36  65  37  71 /   0   0   0   0
ELN  33  62  35  69 /  10   0   0   0
RDM  31  60  31  68 /   0   0   0   0
LGD  33  55  32  61 /  10  10   0   0
GCD  31  56  31  62 /  10   0   0   0
DLS  40  68  41  73 /  20   0   0   0

&&

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

$$

SHORT TERM...75
LONG TERM....83
AVIATION...80