634
FXUS66 KPDT 310939
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
239 AM PDT Fri Jul 31 2026

.KEY MESSAGES...

- Very windy on Saturday, with critical fire weather conditions.

- Diurnal breezes continue Sunday.

- Dry and warm through next week.

&&

.DISCUSSION...
Southwesterly flow continues today around the periphery of a
large high near the four corners, and low pressure off the
British Columbia coast.

The pressure gradient will begin to tonight tonight and continue
to do so into Saturday as the flow becomes more westerly as the
low off the coast moves inland and its associated trough, moves
through the Pacific Northwest. The trough will also bring a dry
cold front with it. No precipitation is expected, but Saturday
is expected to be breezy to windy with wind gusts 35 to 40 mph,
and possibly higher in some areas. NBM probabilities of wind
gusts >=39 mph are generally 80 percent or higher across the
Kittitas Valley, Simcoe Highlands, Columbia Basin, Gorge and
Foothills of the Blue Mountains. However, NBM probabilities of
wind gusts >= 47 mph decrease and while they are locally greater
than 70 percent in a few spots, like the Kittitas Valley, the
broader area is generally 40 percent or less. A wind advisory is
in effect for the Kittitas Valley, and will need to be
monitored for these other locations.

Diurnal breeziness will continue into Sunday with the passage of
a second trough (also dry), but gusts will be lower. NBM
probabilities of wind gusts >= 25 mph is 80 percent or greater
across the Kittitas Valley, Yakima Valley, Simcoe Highlands,
Columbia Basin, Gorge, Blue Mountain Foothills and Central
Oregon. However, probabilities of wind gusts >= 39 mph is
fairly low, generally 20 percent or less, except for a few
isolated locations.

For most of next week, the region is in a dry west to northwest
flow, with warming temperatures.


&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
VFR conditions are expected at all TAF sites except BDN and RDM,
where smoke from wildfires could bring MVFR conditions. Other
sites could have MVFR as well, but probabilities are too low to
include at this time.

DLS will see winds increase toward late after noon and gust
around 25 kts. All other sites will have winds generally 10 kts
or less.

&&

.FIRE WEATHER...
There will be some diurnal breeziness today with very low RH. On
Saturday, there will be a trough and dry cold front passage that
will bring very breezy to windy conditions, especially to the
Kittitas Valley, Columbia Basin, Gorge. However, RH values will
be a bit higher, generally in the 20s and lower 30s in most
areas. Fire Weather Watches remain in effect for Saturday for
winds and humidities. Sunday will still be breezy as a second
trough passes and humidity begins to decrease again. The rest of
the week will see warming temperatures and decreasing humidity
but lighter winds.

&&

.Preliminary Point Temps/PoPs...
PDT  93  62  84  48 /   0   0   0   0
ALW  96  67  87  53 /   0   0   0   0
PSC  96  64  91  52 /   0   0   0   0
YKM  96  63  87  52 /   0   0   0   0
HRI  95  65  86  53 /   0   0   0   0
ELN  93  61  79  50 /   0   0   0   0
RDM  95  53  84  42 /   0   0   0   0
LGD  99  61  88  50 /   0   0   0   0
GCD 101  58  92  50 /   0   0   0   0
DLS  97  65  81  57 /   0   0   0   0

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
WA...Fire Weather Watch from Saturday morning through Saturday
     evening for WAZ691>693.
     Wind Advisory from 11 AM to 11 PM PDT Saturday for WAZ026.
OR...Air Quality Alert until noon PDT today for ORZ041-049-050-502-
     503-505-506-509>511.
     Fire Weather Watch from Saturday morning through Saturday
     evening for ORZ691>700.

&&

$$

DISCUSSION...77
AVIATION...77
FIRE WEATHER...77