Tualatin, Oregon 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

283
FXUS66 KPQR 071747 AAB
AFDPQR

Area Forecast Discussion...UPDATED
National Weather Service Portland OR
1047 AM PDT Sat Jun 7 2025

Updated Aviation...

&&

.SYNOPSIS...A high-amplitude ridge building over the West Coast
will yield a continued warming trend through the weekend. The
hottest days of the year so far are expected Sunday and Monday
in inland valleys where temperatures may surpass 95 degrees,
while the coast and higher terrain remains cooler. Prolonged
exposure to hot temperatures could result in heat-related
illness. The ridge will break down through next week, bringing a
return to more seasonable temperatures.

&&

.SHORT TERM...Now through Monday Night...Upper-level ridging
over the Northeast Pacific continues to build as the ridge axis
steadily approaches the West Coast this weekend. The mid-levels
continue to warm within a region of large-scale descent,
pushing 850-hPa temperatures to 18-20C this afternoon, and even
warmer to 20-22C by Sunday afternoon, some 2-3 std deviations
above normal for this time of year. Deep mixing and abundant
sunshine will realize very warm to hot temperatures inland, as
afternoon highs reach into the upper 80s today, and mid 90s on
Sunday when the ridge axis passes overhead. The ridge will begin
to deamplify and shift eastward on Monday, but persistent warm
temperatures aloft will see a repeat of the heat on Monday
afternoon as well, with record daily high temperatures possible
along the I-5 corridor both afternoons. The southern Willamette
Valley from Corvallis to Cottage Grove will see 25-50% chances
of highs surpassing 95F each of Sunday and Monday, while from
Salem north through Portland/Vancouver will see 50-75% chances.
Overnight temperatures will similarly trend warmer, only falling
to lows in the mid 50s to mid 60s each night, with the warmest
conditions expected Sunday night and especially in urban areas.

The combination of hot daytime and mild overnight temperatures
will yield a Moderate HeatRisk for many inland areas both Sunday
and Monday, excepting only the high Cascades. A Heat Advisory
therefore remains in effect from 10 AM Sunday through 10 PM
Monday across the Willamette Valley and adjacent Cascade
foothills, as well as along the Columbia River from the Cowlitz
and Columbia County lowlands through the Portland/Vancouver
Metro to the Columbia Gorge and Hood River Valley. Areas of
Major HeatRisk are most likely across urban Portland/Vancouver
as well as along the Gorge/Hood River Valley, and upgrades to
Extreme Heat Warnings remain possible if forecast temperatures
trend hotter. Even in the absence of extreme values, prolonged
heat may still pose health risks to sensitive populations. Those
seeking relief in area rivers and lakes should be prepared for
cold water, which can bring its own set of health risks as well.

Meanwhile, coastal areas will see sufficient onshore flow to
remain much cooler than inland areas, albeit still above normal
for those communities. Temperatures will warm through the 60s
to mid 70s, peaking Sunday afternoon. Diurnal clearing followed
by overnight redevelopment of marine stratus will continue with
diminishing coverage through Sunday night. Stronger onshore
flow on Monday as the ridge begins to break down will begin to
see temperatures trend cooler to begin the workweek. -Picard


.LONG TERM...Tuesday through Friday...The ridge will break down
through the workweek as large-scale troughing develops over the
West Coast. While some of the details remain lower confidence,
temperatures will likely return to more seasonable values with
highs in the 60s to low 70s by the latter half of the week.
Embedded shortwaves within the flow passing over the Pacific
Northwest may bring some low chances for rainfall, but at this
lead time, very few global ensemble members suggest any notable
rain accumulations. The 8-14 Day Outlook from CPC favors a
wetter and cooler pattern by the middle of the month. -Picard

&&

.AVIATION...Visible satellite shows stratus rapidly dissipating in
the coastal and inland valleys of northwest Oregon and southwest
Washington as of 18z Sat, yielding clear sky VFR conditions across
the region as high pressure builds overhead. Marine stratus
continues to hug the immediate coastline and may keep IFR cigs at
some of the coastal terminals through around 19z, but clouds should
otherwise be confined offshore through much of the day. Stratus
moves back into the coastal terminals with IFR/LIFR cigs 02-05z Sun,
but do not anticipate much of an inland push tonight as light
offshore flow develops in the mid levels and increasing subsidence
limits the depth of the marine layer. Expect VFR conditions through
the period for the inland terminals, with winds generally under 8
kts.

PDX AND APPROACHES...VFR under clear skies through the period. NW
winds around 5 kt. /CB

&&

.MARINE...An incoming building ridge will move over the area,
bringing typical summer time northerly winds. Could see some
breezier winds through the bays and some exposed moorages, but
wind gusts should remain below 20 kt as the pressure gradient
over the area weakens. Onshore flow returns late Sunday into
Monday as the ridge moves east of the region and breaks down.
Winds will increase into Monday, bringing the potential for
another Small Craft Advisory in the outer coastal waters. As of
now, looks like these Small Craft winds will persist until at
least mid next week. ~Hall

&&

.CLIMATE...

Daily record high temperatures:

Sunday, June 8

Portland94 (1955)
Salem98 (1955)
Eugene93 (2015)
Astoria97 (1903)

Monday, June 9

Portland95 (1955)
Salem96 (1955)
Eugene91 (2015)
Astoria87 (1924)

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...Heat Advisory from 10 AM Sunday to 10 PM PDT Monday for
     ORZ108>123.
WA...Heat Advisory from 10 AM Sunday to 10 PM PDT Monday for
     WAZ204>207-209-210.
PZ...None.

&&

$$

www.weather.gov/portland

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