Kinzua, Oregon Weather Forecast Discussion

495
FXUS66 KPDT 292000
AFDPDT
Area Forecast Discussion
National Weather Service Pendleton OR
100 PM PDT Mon Sep 29 2025
.DISCUSSION...Latest radar imagery currently shows a band of showers
enveloping western WA and OR, slowly moving east. These showers stem
from a deep low centered off the Gulf of Alaska, which will slowly
meander its way toward the PacNW over the course of the week. In the
meantime, this low will circulate a pair of cold fronts through the
region and make for rounds of beneficial wetting rains across our
mountain zones, with light rain expected to occur across the Basin
and adjacent valleys.
The first front is currently bearing down on us, with showers
expected to envelop much of the forecast area by around 3 to 5 PM.
Isolated thunderstorms are possible across central OR and the
eastern mountains this evening, mainly around the Strawberries, but
am a bit skeptical in how aggressive the HREF is in depicting storms
in these areas given the cloud cover and relatively cool air mass
overhead. Should any storms develop, they will primarily be
orographically driven in nature. Will gauge forecast confidence in
storms for these areas at around 20-25%. Scattered showers will
occur elsewhere across the lower elevations this evening.
We`ll see a break in the rain before round two arrives Tuesday night
into Wednesday. Guidance currently suggests that this round won`t be
quite as wet as the showers expected tonight, especially for the
eastern mountains, but could still prove to bring wetting rains for
our mountains. NBM probabilistic guidance currently depicts a high
(>80%) chance for wetting rains for the Cascades and eastern
mountains once these rounds of rain are over with, about 40-70% for
our more elevated valleys such as central Oregon, foothills of the
Blues, and Yakima/Kittitas Valleys, and only about 30% for the lower
Columbia Basin. Even if the Basin is largely spared from heavier
rains, this week`s rain should still wet down ongoing activity
across the Cascades and central Oregon, and hopefully start the home
stretch of this year`s wildfire season.
Models put the trough axis associated with this Alaskan low over our
forecast area around Friday, making for periodic chances of rain
across our mountains after Wednesday with dry conditions elsewhere,
before dry weather prevails area-wide on Saturday under a transitory
ridge. Long-range ensembles appear to depict another northwesterly
low arriving early next week, which should further contribute toward
the closure of this wildfire season. Evans/74
&&
.AVIATION...18z TAFs (Previous Discussion)...A cold front moving
through the region will provide for chances of rain showers across
all sites, mainly late this afternoon through the evening.
Conditions may briefly deteriorate to MVFR under showers
(confidence 30-40%), with isolated thunderstorms possible (chance
15-20%) for BDN and RDM. Rain chances are largely expected to end
for all sites after midnight tonight. Winds could become gusty as
this front initially moves through, but are otherwise expected to
be light at 8-12 kts out of the W/SW. Ovc cigs will give way to
sct-bkn mid-level clouds overnight. Evans/74
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT  50  74  52  69 /  60  20  50  40
ALW  55  74  55  69 /  60  30  50  50
PSC  51  75  51  71 /  40  10  40  30
YKM  45  71  48  69 /  50  20  60  30
HRI  50  74  52  71 /  50  10  40  40
ELN  42  68  43  65 /  60  20  60  30
RDM  37  68  43  66 /  60  30  60  40
LGD  49  72  48  68 /  80  30  40  50
GCD  46  71  47  68 /  70  10  40  30
DLS  50  73  52  70 /  70  50  80  50
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
&&
$$
SHORT TERM...74
LONG TERM....74
AVIATION...74

NWS PDT Office Area Forecast Discussion