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

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Area Forecast Discussion
National Weather Service Portland, OR or
403 am pdt thu jun 11 2026

.synopsis...it`s going to get hot. an upper level ridge
gradually builds over the far northeast pacific then western
wa/or over the next several days ushering in a prolonged stretch
of dry and warm/hot conditions. an extreme heat watch is in
effect sunday afternoon through tuesday evening for the greater
portland/vancouver metro, western columbia gorge, central
willamette valley, and portions of the lower columbia for
daytime highs of 95-100 degrees and overnight lows in the mid
60s or warmer, resulting in major heatrisk. heat related impacts
are anticipated for much of the region. temperatures will trend
cooler for wednesday onward with the return of onshore flow.

&&

.short term...now through friday...we begin an extended period
of completely dry weather today with mostly sunny skies and
noticeably warmer temperatures in the 70s to near 80 across the
inland valleys - a 4-8 degree jump from yesterday (wednesday).
this is all thanks to a ridge of high pressure beginning to
amplify over the eastern pacific which will continue to build
and push closer to the pacific northwest into the first half of
the weekend and beyond. friday is shaping up to largely be a
repeat of thursday, albeit 1-3 degrees warmer as 500 mb heights
increase and 850 mb temperatures warm slightly. while the
persistent onshore flow regime in place during this period will
prevent temperatures from getting too hot, it will facilitate
breezy westerly winds through the central columbia river gorge
from cascade locks eastward, especially during the afternoon and
evening hours when winds are expected to gust as high as 30-35
mph. -99/23

.long term...saturday through next wednesday...heat impacts
drive the long term forecast as it remains highlighted by a
three to four day heat event with the hottest temperatures of
the year thus far expected. during the second half of the
weekend into early next week, the aforementioned ridge of high
pressure off the coast gradually nudges overhead pinching off
most of our onshore influence and allowing temperatures rise
sharply saturday and sunday. an extreme heat watch remains in
effect sunday afternoon through tuesday evening for the greater
portland/vancouver metro, western columbia gorge, central
willamette valley, and portions of the lower columbia for
daytime highs of 95-100 degrees and overnight lows in the mid
60s or warmer, resulting in a major heatrisk. remaining inland
valley locations across southwest wa and northwest or have a
moderate heatrisk, mainly due to relatively cooler overnight
lows. the immediate coast has a minor heatrisk, while inland
coastal communities such as astoria and tillamook have a
moderate heatrisk.

from the slight rise in deterministic and ensemble model
temperatures seen yesterday (wednesday), the latest 00z guidance
remains largely unchanged with forecast high temperatures in
the upper 90s to near 100 degrees for most locations within the
extreme heat watch. confidence has also increased that tuesday
will remain rather toasty (90s), although still not nearly as
hot as monday. model ensemble guidance is in good agreement the
ridge will begin to flatten out over the region on tuesday with
slightly cooler temperatures aloft, morning low temperatures to
start the day will likely be the warmest of any days during the
heat event along the i-5 corridor. given plenty of sunshine in
place and a warm start to the day should the breakdown of the
upper-level ridge delay any further, afternoon highs have the
potential to be nearly as warm as monday. the nbm currently
shows a 20-50% chance for highs of 95 degrees or warmer on
tuesday across the willamette valley and portland/vancouver
metro, and a 10-15% chance for the cowlitz valley, lower
columbia, columbia river gorge, and upper hood river valley.
probabilities for a major heatrisk or higher on tuesday range
between 15-40% in these areas, highest in the portland metro.


anyone who is sensitive to heat or those who have outdoor plans
should prepare for and takes steps to mitigate potential heat
impacts over the next couple of days before temperatures really
ramp up. for those planning to seek relief by swimming in local
area rivers and/or lakes to cool off, be mindful of cold water
temperatures and swift currents which can become life
threatening if precautions like wearing a life jacket are not
taken.

in addition to the heat, there will also be increasing fire weather
concerns in areas with cured grasses and finer fuels. a thermally
induced surface trough will establish itself somewhere west of the
cascade crest starting on saturday helping to strengthening
offshore flow for sunday and monday as well. this will bring
breezy conditions within the western columbia river
gorge/cascades gaps and the willamette valley. as daytime highs
increase, relative humidities will also decrease. given the hot,
dry, breezy conditions expected, there are increasing fire
weather concerns over the weekend through the start of next
week, especially sunday afternoon through monday afternoon. be
aware of potential ignition sources such as chains dragging on
the pavement, hot vehicle components, as well as cigarette butts
as these could easily result in the ignition of cured grasses
and dry, fine fuels. live vegetation and larger fuels may not
have enough time to dry out prior to the dry and breezy
conditions, but this is a variable that is being closely
monitored by our state and federal fire partners.

fortunately, tuesday appears to be the last hot day of the heat
event. come wednesday, june 17, ensemble modeling systems do
depict the ridge finally breaking down and shifting eastward
bringing a return of relatively cooler westerly flow. that said,
the latest ensemble model guidance has nudged temperatures
several degrees higher than previous forecasts - highs now
appear to rise into the upper 70s to mid 80s across the inland
valleys. the slow cooling trend likely (70-80%) extends into
thursday through the end of the week as well. -99/23


.long term...sunday night through wednesday...


&&

.aviation...going through the taf period high pressure will lead
to predominately vfr conditions and mostly clear skies at all
terminals. that said, there remains a 15-30% chance for mvfr or
lower flight conditions due to marine stratus along the coast
between 12-17z today. but due to light offshore winds there is
low confidence this cloud deck and/or fog actually materializes.
winds generally stay out of the north-northwest across the region
and under 10 kt, except tightening pressure gradients in the
afternoon will support gusts up to 20 kt along portions of the
oregon coast especially around and south of konp.

kpdx and approaches...vfr with mostly clear skies through the taf
period with northwesterly winds around 5 to 10 kt or less. -99


.marine...expect a fairly typical summertime weather pattern to
take hold the remainder of the week through the weekend as high
pressure builds offshore over the eastern pacific. this will
allow diurnal northerly winds will strengthen, peaking each
afternoon and evening starting this afternoon but becoming more
noticeable from friday into the early to middle portion of next
week at 15-20 kt with gusts near 25 kt south of cape
foulweather, and trending weaker to the north. due to these
conditions, a small craft advisory has been issued for the inner
and outer waters south of cape foulweather through friday
night. over the weekend, the areal coverage of the small craft
may need to be expanded further north, especially over the outer
waters. seas continue to hold around 4-7 ft at 9-11 seconds
with a persistent westerly swell. models are beginning to hint
at the arrival of a stronger swell towards the end of next week,
although confidence of the arrival and placement of this
feature are low at this time. -99

&&

.marine...


&&

.pqr watches/warnings/advisories...
or...extreme heat watch from sunday morning through tuesday evening
     for orz108>115-120.
wa...extreme heat watch from sunday morning through tuesday evening
     for waz206-207-209.
pz...small craft advisory from 11 am this morning to 5 am pdt
     saturday for pzz253-273.
&&

$$

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