National Weather Service Area Forecast Discussion for Long Beach, WA USA

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Area Forecast Discussion...updated
National Weather Service Portland, OR or
945 pm pdt thu oct 30 2025

...updated aviation and marine discussion, and watches,
warnings, and advisories section...

.synopsis...dry weather with breezy offshore winds continue into
friday before another round of rain associated with a frontal
system arrived friday afternoon into friday night, however some
uncertainty remains in precipitation onset time. drier weather
expected on sunday, but the active weather pattern is likely to
return early next week.

&&

.discussion...now through sunday...the upper-level ridge axis
has shifted east of the cascades early this afternoon, while
surface troughing along the coast continues to support breezy
offshore winds. easterly gusts near cascade and coast range gaps
have reached 35-45 mph so far today, with lesser gusts of 25-35
mph in adjacent areas including the portland/vancouver metro,
and generally 10-15 mph or less elsewhere including much of the
willamette valley. these gusts will ease through tonight as the
pressure gradient across the cascades diminishes. high-level
cirrus clouds near the ridge apex will shift eastward tonight
with brief clearing this evening, before further cloud arrive
onshore ahead of the next approaching weather system. these
increasing high clouds should lessen the risk of frost or fog
development overnight, however areas of frost may occur in the
hood river valley, and fog in the southern willamette valley and
adjacent peripheral valleys in the coast range and cascades.

as an area of surface low pressure moves inland near the haida
gwaii, its trailing frontal boundaries will bring a rain band
onshore friday into friday night. winds shifting onshore from
late friday morning through friday afternoon will begin to
moisten low and mid-levels of the atmosphere, but areas of rain
arriving onshore through the afternoon may still encounter
layers of relatively dry air aloft, yielding increased
uncertainty in the onset time of precipitation. additionally, as
the occluded surface low begins to fill and retrograde into
beneath troughing in the gulf of alaska, a secondary surface low
may develop along the cold front, causing the rain band to stall
along the coast before pushing inland. ultimately, rain will
most likely begin early along the south washington and north
oregon coasts and inland to i-5 near kelso/longview by the
early to mid-afternoon, 2-6 pm. areas south along the oregon
coast along with the greater portland/vancouver metro south to
salem can expect to see rain begin by the late evening, 8-11
pm, while the southern willamette valley including eugene may
not see rain until after midnight. if rain is able to quickly
saturate the column and is not stalled by the development of an
offshore low, precipitation could begin as early the late
morning to mid-afternoon across much of the region, but
confidence is higher that the central and southern willamette
valley will remain dry through at least 8-10 pm. with showers
lingering through much of saturday as the front drops to the
south, total rainfall amounts are most likely going to be
0.75-1.25" along the i-5 corridor, 1-2" along the coast, and
0.5-3" in the cascades, with forecast amounts increasing to the
north in all cases. in the wettest scenario, valley areas will
see 1.25-2.25" while the terrain sees 2-4.5", again with higher
values to the north. even in this scenario, river levels across
the region remain low enough to minimize any flooding risk.

breezy winds are additionally expected through saturday ahead of
and along the cold front. maximum southerly to southwesterly
gusts are expected to reach 20-30 mph inland, and 35-45 mph
along the coast and near the cascade crest. little to no impacts
are expected with these winds. in the windiest scenario, gusts
may reach 50 mph on the coast and 35-40 mph inland, but these
winds are unlikely, with only a 10% chance of occurrence.

sunday night through thursday...conditions dry out by sunday
night as transient upper-level ridging builds overhead. forecast
confidence then decreases into next week, however long-range
ensemble guidance is highlighting the potential for further wet
weather by midweek. troughing over the northeast pacific could
see yet another cold frontal move into the northwest, bringing
increased chances for breezy winds and additional rainfall to
the region. -36

&&

.aviation...satellite imagery and terminal observations as of
late thursday evening depicts mostly vfr conditions across the
region with mvfr cigs at konp. winds have shifted southerly to
southwesterly along the central oregon coast and southern willamette
valley, which is starting to bring in low marine stratus. given the
southerly wind shift, confidence is lower for fog development
tonight in the south valley as southerly winds will bring warmer
temperatures and thus a wider dewpoint depression. there is still a
20-30% chance for fog development across the central and northern
willamette valley, but high clouds and stronger winds may prevent
fog development. what`s more likely is low stratus entering the
willamette valley early friday morning.
guidance suggests a 40-60% chance for ifr/mvfr cigs across the
valley between 11-16z fri.

low stratus in the valley should dissipate after 16-18z fri with
daytime heating. will also see increasing bkn/ovc high clouds ahead
of the next frontal system. this front will likely (>70% chance)
bring widespread mvfr cigs along the coast after 21z fri, with rain
beginning along the north oregon coast. rain will gradually spread
southeastward and inland friday evening. expect southerly winds with
gusts up to 20 kt along the coast, and generally 10 kt inland. light
easterly winds continue in the far eastern portland metro.

kpdx and approaches...vfr conditions through the taf period with
increasing high clouds ahead of the next system. will maintain
offshore pressure gradient with east-southeasterly winds around 7-10
kt. light rain and low-end vfr cigs arrives 00-06z sat.    -10

&&

.marine...high pressure gradually weakens over the coastal waters
today. southerly winds increase on friday as a warm frontal system
approaches the coastal waters from the north. the probability for
gale force winds have decreased to around 40% from 30 nm westward in
pzz271-272. because the probability has decreased, the gale watch
has been dropped and a small craft advisory has been put into
effect. the advisory though will be a high end advisory as gusts up
to 30 kt are expected. cannot rule out a stray gust up to 35 kt, but
they are not expected to be widespread or persistent. if they do
occur, the peak time frame would be between 11 am to 3 pm fri.

models continue to fluctuate with this first frontal system followed
by a smaller secondary low. this second low does not appear to be
overly robust so expecting minimal impacts. however, if it does form
it will enhance the westerly swell and bring upon a stronger
southerly wind wave. therefore will see seas increase further. there
is a high probability of hazardous seas conditions late friday night
into saturday morning; therefore, a hazardous seas warning has been
issued across all waters from 11 pm fri to 8 pm sat.       -10/27

&&

.pqr watches/warnings/advisories...

or...none.
wa...none.
pz...small craft advisory from 8 am to 11 pm pdt friday for pzz210-
     251>253-271>273.

     hazardous seas warning from 11 pm friday to 8 pm pdt saturday
     for pzz210-251>253-271>273.
&&

$$

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