969
FXUS66 KPDT 122122
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
222 PM PDT Fri Jun 12 2026

.KEY MESSAGES...

- Warming and drying trend extends into next week.

- Breezy weekend winds will increase early next week.

- Windy and dry conditions elevate fire weather concerns.

&&

.DISCUSSION...
Current radar and visible satellite imagery shows dry conditions
under clear skies. This is in response to an upper level high
pressure system that is strengthening offshore today before
slowly moving onshore late Saturday and crossing through the
Pacific Northwest on Sunday. A warming trend will ensue as the
warm and dry airmass associated with the high pressure ridge
moves over the area. High temperatures will reach into the low
to mid-80s today, mid-to upper 80s Saturday, low 90s Sunday, and
into the mid-to upper 90s Monday and Tuesday across lower
elevations of the Columbia Basin, Blue Mountain foothills,
Columbia Gorge, and Central Oregon. High temperatures Monday and
Tuesday are about 15 degrees above normal for this time of
year. Overnight relief will be minimal as morning lows Monday
and Tuesday will only dip into the low-to-mid-60s across lower
elevations of the Columbia Basin, Blue Mountain foothills,
Columbia Gorge, and the Yakima Valley. As a result, widespread
moderate (2 of 4) HeatRisk is expected Monday, with isolated
areas on Sunday and Tuesday. Probabilistic HeatRisk suggests an
80-100% chance of Moderate HeatRisk being reached on Monday
across these areas, with some areas along the Gorge, Tri-Cities,
and Yakima included in a 40-60% chance of Major (3 of 4) or
Extreme (4 of 4) HeatRisk. There are some model inconsistencies
with the strength and timing of the ridge with 45% of members
suggesting a weaker or later ridge progression onshore. However,
these differences are rather minor, and should only result in
temperature differences of 2-4 degrees. As confidence grows, so
does the potential for heat products being issued as either an
advisory or warning. At this time, an advisory is probable
(50-70%) Monday across the Columbia Gorge, Yakima Valley, and
Central Oregon, depending on the introduction of CAMs guidance
over the next 24 hours.

The ridge slides onshore over the weekend and suppresses on
Monday due to an incoming upper level trough from the northwest.
The pressure gradient will tighten between these two synoptic
features late Monday and Tuesday, enhancing winds across the
area. The strongest winds are expected to occur between Tuesday
afternoon through Wednesday morning as gusts up to 65 mph will
be possible through the Kittitas Valley, and up to 55 mph over
the Simcoe Highlands, Columbia Gorge, north-central Oregon, and
the Blue Mountain foothills. The NBM advertises a 30-50% chance
of high wind warning level wind gusts (>58+ mph) through the
Kittitas Valley and a 50-70% chance of advisory-level (>45+ mph)
wind gusts over the remaining areas of the Columbia Gorge,
Simcoe Highlands, and the Blue Mountain foothills. The
uncertainties in timing and strength of the incoming trough and
attendant cold front also relate to confidence in these wind
values, with 25% of members highlighting higher winds than the
current forecast and 30% of members swinging in the other
direction of weaker winds. This will have to be analyzed further
as the event nears and details from short-term guidance can be
assessed.

The combination of warm temperatures, dry conditions, and high
winds provide elevated fire weather concerns that peak on
Tuesday. Even though afternoon humidity values hover in the low
to mid-teens through Monday, the lack of enhanced winds
coinciding with these values suppresses fire weather concerns.
However, the passing of a cold front Tuesday will bring windy
conditions, moderate (30-50%) overnight humidity recoveries, and
afternoon humidities in the mid-to upper teens across some zones
that have receptive fuels. These would include areas of Central
Oregon and the Lower Columbia Basin. Timing looks to be most of
the day on Tuesday after mid-to late morning. Stay tuned.



&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
VFR conditions currently across all sites, which will stay the
course through the period. Wind gusts between 20-30kts are
being experienced at KDLS, with wind gusts of 15-25kts expected
later this afternoon for KPDT/KRDM/KBDN/KYKM. Winds will subside
later the evening across all terminals under broken 25kft
ceilings. 75

&&

.FIRE WEATHER...
As stated in the primary forecast discussion, fire weather
concerns peak Tuesday across much of the Columbia Basin
(WA/OR691) and Central Oregon (OR700, OR704, and OR705). These
zones encompass all currently declared fire weather zones, as
fuels within these zones have been found to be receptive to
carry and spread fire. There are isolated pockets of fire
weather concerns over the weekend and even into Monday,
primarily related to areas of north-central Oregon (OR703) and
southern Blue Mountains/foothills, (SW OR691) mid-to late
afternoon. The passing of a cold front on Tuesday will also lead
to an increase in instability and shifting wind directions
along the frontal boundary. This may warrant a Fire Weather
Watch being issued in the next 24-48 hours related to Tuesday`s
event (50-60% confidence). 75

&&

.Preliminary Point Temps/PoPs...
PDT  48  84  49  87 /   0   0   0   0
ALW  53  84  54  87 /   0   0   0   0
PSC  53  88  56  91 /   0   0   0   0
YKM  53  87  56  91 /   0   0   0   0
HRI  51  87  54  90 /   0   0   0   0
ELN  49  82  53  87 /   0   0   0   0
RDM  44  83  47  86 /   0   0   0   0
LGD  45  81  47  84 /   0   0   0   0
GCD  43  83  45  87 /   0   0   0   0
DLS  56  89  61  93 /   0   0   0   0

&&

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

&&

$$

DISCUSSION...75
AVIATION...75
FIRE WEATHER...75