Mehama, Oregon Weather Forecast Discussion

379
FXUS66 KPQR 262204
AFDPQR
Area Forecast Discussion
National Weather Service Portland OR
304 PM PDT Fri Sep 26 2025
.SYNOPSIS...Conditions will be dry and mild through Sunday,
with the warmest temperatures expected on Saturday as high
pressure remains over the region. The first in a series of
Pacific frontal system will bring widespread rain to the area
Sunday night into Monday. Conditions remain cool and showery
through at least the middle of next week as additional frontal
systems move into the region. The strongest system currently is
expected Tuesday through Wednesday and will bring breezy south
winds, however uncertainty remains high for exact wind speeds and
associated impacts.
&&
.DISCUSSION...Friday night through Thursday night...High clouds will
increase from the west Friday night into Saturday morning as a weak
upper level impulse moves overhead. The airmass with this feature is
too dry for precipitation to occur, hence the reason the forecast
remains dry in the short term. High clouds should decrease from west
to east Saturday afternoon. It appears high clouds will be thin,
which will make it appear mostly sunny with filtered sunshine. Still
expecting high temperatures in the upper 70s to around 80 degrees
over the interior lowlands, with highs in the 60s at the coast.
Saturday is still the warmest day for the foreseeable future.
Sunday should be a few degrees cooler due to more substantial cloud
cover and slightly cooler temperatures aloft. This increase in cloud
cover will be in response to a slow-moving Pacific cold front that is
set to approach the coast late in the day. Due to the slow motion of
this front, Sunday will likely stay dry. However, stratiform rain
will eventually spread over the area Sunday night into Monday, most
likely beginning at the coast overnight when PoPs increase to 80-90%,
and for inland areas Monday morning when PoPs also increase to
80-90%. Stratiform rain will transition to off-and-on rain showers
Monday afternoon/evening in the post-frontal environment.
It appears there will be a brief break in precipitation Monday night
into Tuesday, before another weather system arrives late Tuesday into
Wednesday. This system will likely be stronger than the Sunday
night/Monday system, at least in regards to wind speeds and rain
amounts. That said, uncertainty is high for exact wind speeds, as the
outcome will be highly dependent on the exact strength and track of a
vertically stacked closed low pressure system over the northeast
Pacific. A small subset of ensemble guidance suggests this low will
move towards the coast while remaining strong, resulting in gusty
south winds up to 40-50 mph for the coast and possibly even for
inland areas. However, the probability for wind gusts of 45 mph or
stronger is low (10% or less for inland areas, 20-30% for coastal
areas). While this is far from being the most likely outcome, it is
worth mentioning as wind speeds of this magnitude would be enough to
result in tree damage and some power outages, especially when
considering the fact that leaves are still on trees. Although
confidence is low when it comes to wind speeds, confidence is high
conditions will at least be cool and wet. Chances for showers remain
in the forecast Thursday and Thursday night with cool temperatures
continuing. -TK
&&
.AVIATION...Westerly flow aloft as weak high pressure persists
over the region today. This will maintain predominately VFR
conditions through the period. Expect increasing high clouds
tonight into Saturday morning as the upper level ridge shifts east
and flow aloft becomes southwesterly. Winds remain relatively
light at the surface, except NNW around 10 kt near KONP to KEUG
this afternoon. There are low (10-20%) chance of marine stratus
developing along the coast after 12z Saturday.
KPDX AND APPROACHES...Mostly clear skies today will result in VFR
through the period. High clouds expected to increase across the
area later tonight into Saturday morning. Northwest winds around
4-6 kt expected this afternoon. /DH
&&
.MARINE...Relatively light winds of 10 kt or less expected through
Saturday as a frontal band remains stalled well offshore to the
north and west, and surface high pressure continues to gradually
weaken over the coastal waters. Seas around 6 to 7 ft slowly build
to around 8 to 10 ft on Saturday as a mid-period northwest swell
moves into the waters. Have issued a Small Craft Advisory for just
the outer waters north of Cape Falcon on Saturday as seas are
expected to linger around 10 ft into the evening.
A frontal system will approach the waters on Sunday with
increasing southerly winds through Sunday night. At this time
there remains around a 30% chance of gale force wind gusts
exceeding 34 kt before the cold front pushes inland Monday
morning. A potentially strong low pressure system is forecast to
develop in the NE Pacific on Tuesday. Guidance is showing around a
70-80% chance of widespread Gales across the waters with this
system. Combined seas are currently forecast to climb into the
lower to mid-teens, but there is around a 5-10% chance of seas
building to 20 ft into the middle of next week. /Hartsock
&&
.BEACH HAZARDS...A northwest swell around 7 to 10 ft at 14-15
seconds will bring an increased threat of sneaker waves this
afternoon through Saturday evening. Beach goers should remain
aware of their surroundings. Waves can run up significantly
farther on a beach than normal, including over rocks and jetties.
Sneaker waves can suddenly knock people off their feet and quickly
pull them into the frigid ocean which may lead to serious injury
or drowning. /DH
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory from 11 AM to 8 PM PDT Saturday for PZZ271.
&&
$$
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NWS PQR Office Area Forecast Discussion