415
FXUS66 KPDT 292147
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
Issued by National Weather Service Seattle WA
247 PM PDT Wed Jul 29 2026

.KEY MESSAGES...

1. Dry conditions will persist through the week.

2. Slight Chances of dry thunderstorms Wednesday and Thursday.

3. Diurnally breezy winds and low RHs.

&&

.DISCUSSION...
Satellite and radar continue to advertise mostly clear and dry
conditions across the region thanks to the upper level ridge
situated near the four corners. Areas of smoke and haze are
still present with winds generally from the southwest, pushing
smoke transport across Central Oregon through Northeast Oregon.
Air Quality continues to be sub-par through noon on Friday as an
Air Quality Advisory is issued (via the Oregon Department of
Environmental Quality) for counties near Central Oregon and the
Eastern Mountains.

Very low potential (up to 5% chance) for dry thunderstorms to
develop from Central Oregon through the Eastern Mountains during
peak day-time heating hours today and tomorrow. Guidance is in
good agreement that a small pocket of low to mid level moisture
will move over the previously mentioned areas through the next
24-hours with models struggling to forecast for the MUCAPE
values for the lifting mechanism. GFS, NAM, and the ECMWF are
all over the place with MUCAPE values with NAM being the most
aggressive with 300-500 J/kg, GFS putting almost nothing
developing, and the ECMWF somewhere in the middle. Regardless,
chances remain very low and are not expected to be widespread if
storms develop.

Through Friday: The upper level ridge will push slightly more
to the west (>85% chance) with a trough just situated to the
northeast. Diurnal wind breezes will continue, with breezier
winds near the mountain gaps and parts of the Basin. Dry
conditions persist with minimum relative humidity values
dropping to the mid-teens to lower 20 percent range and with
slightly enhanced diurnal breezes with the upcoming shortwave,
elevated fire weather conditions will persist at least through
this period.

Saturday: The approaching shortwave will bring tight pressure
gradients to move-in to the region, allowing for breezy to
locally windy conditions to develop. NBM advertises 50-70%
chances of winds exceeding wind advisory (>45 mph gusts)
Saturday across the Kittitas Valley, Simcoe Highlands, and parts
of the Columbia Basin. Wind highlights have not been issued,
but additional monitoring may be needed as the event gets
closer. On the fire weather side, minimum relative humiditys
recover slightly into the 20 to 30 percent range, but its put
off by the stronger developing winds. A Fire Weather Watch has
been issued for the Columbia Basin and the eastern part of
Wallowa County following the anticipation of overlapping breezy
winds and low relative humidity levels. Additional fire wx
highlights are possible as more guidance comes through with
increased confidence of an issuance.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
VFR conditions currently across all sites, which will stay the
course through the period. Breezy winds currently across
KDLS/KRDM/KBDN will slowly subside this evening from sustained
winds of 10-15kts and gusts of 20-25kts. Light winds of 10kts or
less tonight into Thursday morning, with diurnal winds picking
up for KDLS/KRDM/KBDN in the afternoon.

&&

.Preliminary Point Temps/PoPs...
PDT  56  88  55  91 /   0   0   0   0
ALW  62  90  61  93 /   0   0   0   0
PSC  60  92  59  95 /   0   0   0   0
YKM  58  91  59  94 /   0   0   0   0
HRI  60  91  59  94 /   0   0   0   0
ELN  55  86  56  91 /   0   0   0   0
RDM  48  88  49  93 /   0   0   0   0
LGD  57  92  56  97 /   0   0   0   0
GCD  55  94  56  98 /   0   0   0   0
DLS  60  86  59  92 /   0   0   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
WA...Fire Weather Watch from Saturday morning through Saturday
     evening for WAZ691.
OR...Air Quality Alert until noon PDT Friday for ORZ041-049-050-502-
     503-505-506-509>511.
     Fire Weather Watch from Saturday morning through Saturday
     evening for ORZ691-693.

&&

$$

DISCUSSION...95
AVIATION...75