282 
FXUS66 KPDT 252022
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
122 PM PDT Thu Sep 25 2025

.DISCUSSION...
The key impacts during the next seven days will largely be
confined to the next 6-12 hours as Red Flag conditions affect a 
large chunk of southeast WA and portions of central/northeast OR. 
A cold front, extending south from a surface low over northeast 
WA, will move across the CWA this afternoon, resulting in a tight 
pressure gradient across the Cascades. Gusty west winds have 
developed in response to this gradient, with gusts exceeding 35 
mph at times in the Kittitas Valley and Columbia River Gorge. 
Gusts will top out in the 45-55 mph range in the Kittitas Valley 
this afternoon and evening; thus, the Wind Advisory will remain in
effect. RH values will drop to 10-20% across much of the CWA this
afternoon, as downsloping and mid-level dry air tend to 
"overachieve" relative to numerical guidance. 

The dry cold front will traverse the area during the daytime
hours, moving east of the CWA by sunset. The 12z REFS/HRRR 
indicates a fair amount of vertically integrated smoke emanating 
southeast from the Labor Mountain wildfire across the Tri-Cities 
into the Blue Mountains this evening. Winds will be slow to 
diminish in the Cascade gaps this evening, eventually becoming 
light area wide as the surface anticyclone nudges into the area. 
Cooler air will settle over southeast WA/northeast OR for tomorrow
with high temperatures much closer to climatology. 

Generally pleasant weather is expected through most of the weekend 
with temperatures running a few degrees above normal both Saturday
and Sunday. Highs will top out in the mid 70s to lower 80s with 
overnight lows in the mid 40s to lower 50s (mid/upper 30s in the 
higher elevations of central and northeast OR). An upper-level 
trough will begin to deepen over the Gulf of Alaska this weekend, 
resulting in increasing southwesterly flow aloft by Sunday. The 
pressure gradient will tighten somewhat on Sunday ahead of the 
next cold front, potentially increasing southwest winds across 
central OR Sunday afternoon. At this time, critical fire weather 
conditions are not anticipated with both wind and RH currently 
forecast to remain in check. That said, this is something to 
watch.

There are some synoptic scale differences in the various global  
ensemble clusters early next week with the GEFS favoring a deeper 
trough, the GEPS highlighting a faster trough, and the EPS
trending toward a slower system. Regardless of these timing and 
amplitude differences, sensible weather doesn't look to differ 
much with similar QPF suggested by all three clusters. The 
probability for a wetting rain early next week falls in the 70-90%
range for most areas with some of the Columbia Basin areas more 
in the 40-70% window. Rainfall probabilities for 0.25" to 0.5" are
generally at or above 60% for the Cascade peaks and from central 
OR through the Blue Mountains. Temperatures during this early week
precipitation event will be near to slightly below normal with 
drier conditions settling over the region by the latter half of 
the week. /MJ

&&

.AVIATION...
18z TAFs...VFR conditions currently prevail area-wide 
and are expected to continue over the next 24-hrs. A dry cold front 
is starting to work into northwest WA that will eventually enter and 
cross the area late this afternoon. Ahead of the front, breezy W-NW 
winds are anticipated with some terminals starting to see winds 
increase, such as KPDT. These increasing winds late morning-early 
afternoon could be attributable to strong cross-Cascade pressure 
differences that is sharpening. These breezes will then be 
maintained as the front moves through promoting breezy winds through 
the evening hours. Winds should start subsiding 3-9 UTC tonight with 
light winds prevailing the remainder of tonight. Otherwise, 
increasing high clouds are expected this evening-overnight.

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  46  72  46  80 /   0   0   0   0 
ALW  50  72  51  80 /   0   0   0   0 
PSC  46  74  45  78 /   0   0   0   0 
YKM  45  74  48  79 /   0   0   0   0 
HRI  47  74  45  79 /   0   0   0   0 
ELN  44  72  44  78 /   0   0   0   0 
RDM  36  73  38  83 /   0   0   0   0 
LGD  41  71  42  81 /   0   0   0   0 
GCD  40  72  43  85 /   0   0   0   0 
DLS  49  78  51  83 /   0   0   0   0 

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Red Flag Warning until 11 PM PDT this evening for ORZ691-701-703.

WA...Red Flag Warning until 11 PM PDT this evening for WAZ690-691-695.

     Wind Advisory until 2 AM PDT Friday for WAZ026.

&&

$$

DISCUSSION...MJ
AVIATION...80