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

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Area Forecast Discussion
National Weather Service Portland, OR or
1040 am pdt sat jun 13 2026

updated aviation discussion

.synopsis...upper level high pressure over the far northeast
pacific builds into into western wa/or over the next several
days, ushering in a prolonged stretch of dry and hot conditions.
daytime temperatures increase significantly this weekend into
early next week, peaking sunday and monday with interior
lowlands in the upper 90s to around 100 degrees. low
temperatures will not provide much relief from the heat. heat
related impacts are anticipated for much of the region with
widespread moderate to high heatrisk. temperatures will trend
cooler for wednesday onward with the return of onshore flow.

&&

.discussion...saturday through friday...a multi-day heat event
begins today for nw or and sw wa as strong upper level high
pressure over the far e pacific begins moving east towards the
pacnw coastline. at the surface, a thermal trough west of the
cascades is spreading north from s or into n or and will remain
in place into monday morning, introducing offshore flow across
the area, which will have an additional warming and drying
effect for many locations. daytime temperatures today are
forecast to peak in the upper 80s to low 90s across the interior
lowlands and portions of the coast range, around 10-15 degrees
warmer than yesterday and roughly 15-20 degrees warmer than
daily high temperature normals (around 72-74 degrees). the coast
will also be warmer than normal, peaking in the mid to upper
70s.

temperatures rise further and peak on sunday into monday as the
ridge axis continues shifting east over the coastline. daytime
temperatures are expected in the mid to upper 90s for sunday
and monday for the interior lowlands and portions of the or
coast range with some locations forecast to exceed 100 degrees
on monday. sunday will the the hottest day for the coast,
peaking near 80 degrees due to the location of the ridge axis
plus offshore flow. probabilities for temperatures exceeding 95
degrees are around 70-90% between salem and vancouver and
50-70% for the rest of the willamette valley on sunday. there
is less than a 5% chance for the cowlitz valley lowlands and
gorge. on monday, probabilities for 95 degrees rise
considerably with the nbm showing around a 85-99% chance of in
the willamette valley and around 40-60% in the cowlitz valley.
with monday being the hottest day in the forecast, there is
around a 50-70% chance of temperatures reaching 100 degrees or
more between salem and portland.

low temperatures are not expected to provide much relief from
the daytime heat saturday night into sunday morning through
monday night into tuesday morning, especially sunday night into
monday morning. low temperatures are likely to remain above
60-65 degrees in the interior lowlands and the coast range. low
temperatures could even remain above 70 degrees in some
locations sunday night into monday morning with around a 25%
chance for the greater portland- vancouver metro area and coast
range.

ensemble guidance indicates high pressure continues tuesday
with heights beginning to lower along with 850 mb temperatures,
which would allow for lowering temperatures on tuesday. however,
there is uncertainty in the forecast spread of both of these
elements, leading to uncertainty in the high temperature for
tuesday. additionally, it is not uncommon for models to degrade
highly amplified ridges such as this one too early in the
extended forecast period. there is no robust weather system in
the models that is causing the lowering heights, so there is the
potential that the high pressure may not break down as much as
ensembles indicate on tuesday. nbm still indicates warm daytime
temperatures at least in the upper 80s for the interior
lowlands. ensembles are in good agreement that the surface
thermal trough over or will break down sometime monday into
tuesday, which combined with the flattening ridge will allow for
onshore flow to return. because of this, tuesday is not
expected to be quite as warm for the coast and coast range as
previous days, and the sw wa lowlands could be quite cooler than
the willamette valley. either way, past heat events have shown
that impacts from the heat can continue despite a cool- down,
especially since morning low temperatures are expected to remain
very warm tuesday morning.

an extreme heat warning remains in effect for the greater
portland metro area and western columbia river gorge and heat
advisories for the rest of the region west of the cascades for
11 am sunday through 11 pm tuesday. the combination of very hot
daytime temperatures and warm overnight temperatures will create
moderate to major heatrisk across the majority of nw or and sw
wa, excluding the cascades. this means most of the general
population will be susceptible to heat-related illness,
especially those without access to air conditioning and those
spending extended time outdoors. additionally, many high and low
temperatures could break records with this event. those records
can be seen in the "climate" section below.

in addition to the heat, the tightening surface pressure
gradients associated with the surface thermal trough will lead
to breezy offshore winds today and sunday, especially within the
central and southern willamette valley in the afternoon and
evening hours and the columbia river gorge and western cascade
gaps in the evening and overnight hours. additionally, as
daytime temperatures increase, relative humidities will also
decrease to near critical levels. this is producing some fire
weather concerns in areas with cured grasses and finer fuels
saturday into monday due to hot, dry, and breezy conditions.
based on feedback from area partners, fuels are not quite cured
enough to consider any red flag warnings at this point, but
there is uncertainty on how the fuels will be impacted by the
continuous days of dry and hot conditions. currently, there is
around a 15-40% chance of relative humidity being below 25% and
winds being greater than 15 mph on saturday and sunday. be
aware of potential ignition sources such as vehicle chains
dragging on the pavement, hot vehicle components, sparks created
by power tools, and cigarette butts as all of 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.

ensemble guidance indicates the high pressure axis shifts west
back over the e pacific wednesday into late next week as a
strong upper trough digs into the midwest. however, uncertainty
in the strength of the trough leads to uncertainty in the high
pressure over the western us/e pacific. there is high confidence
that temperatures will be quite cooler than sunday and monday,
but 50-60% of ensemble members still keep just enough high
pressure over the region for high temperatures to remain in the
low to mid 80s for the interior lowlands. -03/27

&&

.aviation...high pressure will maintain vfr conditions with clear
skies through the taf period across all terminals. north to
northeasterly winds expected, except northwesterly at the coast.
surface pressure gradients tighten this afternoon supporting gusty
winds up to 20-25 kt at any given terminal. after 03-04z sunday,
winds should gradually weaken as pressure gradients ease and winds
turn back offshore at the coast.

in addition, temperatures between 90 to 100 degrees are forecast
across the willamette valley saturday through monday. be aware of
high density altitude which may reduce aircraft performance.

kpdx and approaches...vfr with clear skies through the taf period.
northwesterly winds around 5 kt turn more northeasterly after
18-20z with gusts up to 20 kt through the afternoon. winds weaken
later in the evening after 03-04z sunday. /dh

&&

.marine...expect a typical summertime pattern to persist into
next week as high pressure builds offshore. diurnal northerly
winds will strengthen, peaking each afternoon and evening. expect
winds of 15-25 kt with gusts up to 25-30 kt south of cape falcon
each afternoon and evening. on saturday, breezy winds could extend
north of cape falcon with gusts up to 25 kts. overnight, wind
gusts may fall below small craft criteria for the inner water
zones, but still expecting gusts up to 25 kt for the outer waters.
small craft advisory for locations south of cape falcon has been
extended through 5 am pdt monday, and a small craft advisory has
been issued for zones north of cape falcon from 2 pm pdt today
through 2 am pdt sunday. seas 4-7 ft at 9-11 seconds persist with
a persistent westerly swell.

a very strong ebb current is expected for the columbia river bar
this morning around 3:30 am pdt and again sunday morning around
4:30 am with seas around 6-7 ft. a small craft advisory has been
issued until 6 am pdt this morning due to this very strong ebb.

long-range guidance brings a more active weather pattern towards
the end of next week, which could result in seas near 10 ft as
well as gusts up to 30 kt. however, overall confidence in this
pattern change is low at this time. -03

&&

climate...

record high temperatures and warm low temperatures for sunday,
june 14

 high temperatures: warm low temperatures:
portland int`l 89f (1988) 62f (1985)
vancouver, wa  93f (1986)  61f (1931)
hillsboro  96f (1961)  60f (1963)
mcminnville  93f (1986)  59f (1936)
salem  92f (1961)  59f (1936)
eugene  92f (1914)  57f (1993)
astoria  86f (1914) 58f (1972)

record high temperatures and warm low temperatures for monday,
june 15

 high temperatures: warm low temperatures:
portland int`l 95f (1966) 60f (1969)
vancouver, wa 95f (1930, 1966)   62f (1961)
hillsboro 99f (1961) 60f (1963)
mcminnville 96f (1961) 59f (1936)
salem100f (1966) 59f (1931)
eugene 96f (1966) 60f (1961)
astoria 91f (1966) 58f (1997)

record high temperatures and warm low temperatures for tuesday,
june 16

 high temperatures: warm low temperatures:
portland int`l 95f (1958) 60f (2012)
vancouver, wa 92f (1961)   67f (1966)
hillsboro100f (1961) 65f (1961)
mcminnville 98f (1961) 59f (1966)
salem 97f (1961) 61f (1961)
eugene 95f (1961) 62f (1961)
astoria 87f (1958) 59f (1997)

&&

.pqr watches/warnings/advisories...

or...heat advisory from 11 am to 11 pm pdt sunday for orz101>103.

     heat advisory from 11 am sunday to 11 pm pdt tuesday for
     orz104>108-113>119-121>125.

     extreme heat warning from 11 am sunday to 11 pm pdt tuesday for
     orz109>112-120.

wa...heat advisory from 11 am to 11 pm pdt sunday for waz201.

     heat advisory from 11 am sunday to 11 pm pdt tuesday for
     waz202>205-208-210.

     extreme heat warning from 11 am sunday to 11 pm pdt tuesday for
     waz206-207-209.

pz...small craft advisory from 2 pm this afternoon to 2 am pdt sunday
     for pzz251-271.

     small craft advisory until 5 am pdt monday for pzz252-253-272-
     273.
&&

$$

www.weather.gov/portland

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