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

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Area Forecast Discussion
National Weather Service Portland, OR or
1110 am pdt fri may 15 2026

updated aviation discussion.

&&

.synopsis...showers return this morning to the northern coast,
spreading inland this afternoon as a weak frontal system moves
across the area. low pressure over western washington and upper
level troughing will maintain showers with seasonably cool
temperatures through saturday, as well as a 10-20% chance of
afternoon thunderstorms, generally north of salem. cooler temps
will also bring snow levels down to 3500-4000 ft, allowing for
light snow along the cascade passes tonight through saturday
night. drier and warmer weather returns sunday through next week
as high pressure re- builds.

&&

.discussion...water vapor satellite imagery early this morning shows
the leading edge of an upper level jet stream over the northern
pacific pushing toward the pacnw. this will push another relatively
weak frontal system across the area, with the highest chances for
precipitation along the coast and northern portions of the forecast
area through this evening. this system will also bring breezy
southwesterly winds with gusts up to 25 mph across the area later
this afternoon.

broad upper level troughing dropping out of the gulf of alaska will
slide across the region tonight cooling temperatures aloft, with
ensembles suggesting 850 mb temps dropping down to around -2 c. this
will allow snow levels to fall to around 3500-4000 ft (lowest across
the sw washington cascades). weak surface low pressure will linger
near the puget sound tonight through saturday while shortwave
disturbances maintain shower activity overnight through at least
saturday afternoon. orographics of the coast range and cascades will
likely enhance precipitation as west to northwesterly flow persists.
this may lead to some accumulating snow, especially at higher
elevations. latest guidance suggests there is anywhere from a 20-60%
chance of exceeding 6 inches of snow (in a 24-hr period) at cascade
passes, highest near government camp. if planning on traveling to
the cascades, make sure to check the latest forecast, refer to
odot/wsdot for the latest road conditions, and pack an emergency
supply kit. considering many of the forest roads are free of snow
from the early melt-out and access to unmaintained roads is growing,
the lower snow levels may catch people off guard if they are
unprepared for cold, wet, and even snowy conditions.

while rainfall amounts in the lowlands are expected to be light and
non-impactful, there is also a 15-20% chance for short-lived
thunderstorms saturday afternoon, mainly from lincoln city/salem
northward. colder air aloft filtering in from the passing trough
will gradually increase atmospheric instability, especially in the
afternoon, though only about 100-300 j/kg of skinny cape. any
thunderstorms that do develop may produce lightning, brief heavy
downpours, small hail, and erratic winds.

after seasonably cool temperatures today and saturday, expect a
warming trend to return sunday through early next week. as the upper
level trough shifts east, expect high pressure to return back over
the region. ensemble guidance is is general agreement that upper
level ridging builds into the ne pacific. but, there remains
uncertainty with how far east the ridge progresses toward the pacnw.
the farther east the ridge does shift over the pacific nw,
temperatures are more likely to see higher end amounts, mid to upper
70s by the middle of next week. if the region stays under more
northwesterly flow aloft, afternoon temps would be more likely to
remain in the upper 60s to lower 70s. the majority of ensemble
guidance does return to mostly dry conditions for next week. /dh

&&

.aviation...predominately vfr conditions continue as shower
activity increases over the forecast area. another front is on its
way through northern or with chances for mvfr cigs increasing
through the afternoon. rain is expected to spread south and east
through the day, with chances for mvfr conditions developing at
konp and kast increasing to around 30-50% by 21z. chances for
mvfr conditions inland generally remain around 30% or less after
00z saturday, highest near kpdx/kttd and northward. southwesterly
winds are also expected to increase this afternoon, with gusts up
to 25 kt at the coast and to around 20 kt inland.

kpdx and approaches...predominately vfr conditions are expected
through the period, though chances for mvfr increase this
afternoon into this evening to around 20-30% as rain showers
increase across the area. southwest winds are expected to increase
to around 9-13 kt with gusts up to 20 kt later this afternoon.
-19/dh

&&

.marine...onshore winds continue today into the weekend as a
weak frontal passage will bring another round of elevated
westerly winds with gusts up to 25 kt later this afternoon. a
mid-period west-northwesterly swell will also help build seas to
around 10 to 12 ft tonight into saturday morning. therefore,
small craft advisories remain in effect this afternoon through
late saturday. additionally, very strong ebb currents across the
columbia river bar early friday and saturday mornings will
shorten the wave period and result in steeper seas.

northerly to northwesterly winds return sunday into early next
week while seas ease to around 4 to 8 ft as high pressure builds
offshore. strong currents during morning ebb tides will continue
daily through thursday, potentially yielding steep and hazardous
seas for small craft crossing area bars through much of the week.
/dh

&&

.pqr watches/warnings/advisories...

or...none.

wa...none.

pz...small craft advisory until 2 am pdt sunday for pzz210-251-271-
     272.

     small craft advisory from 5 am saturday to 2 am pdt sunday for
     pzz252-253-273.

&&

$$

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