146
FXUS66 KPQR 022335
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
435 PM PDT Mon Jun 2 2025

.Updated Aviation discussion...

.SYNOPSIS...PacNW will be under northwest flow between a ridge
over the northeast Pacific and the base of a large trough across
the Great Basin. Conditions will be dry with slightly above
average temps. Temps trend upward toward the end of the week and
into the weekend with the warmest conditions of the year so far
possible on Sunday.

&&

.DISCUSSION...Now through Sunday...A dry, pleasant pattern
will remain in place across the area through mid week. A ridge
of high pressure across the northeast Pacific with the base of a
large trough extending into the Great Basin, supporting
northwest flow in the upper levels across the PacNW. Temps
through Wednesday will top out in the mid to upper 70s inland
and low to mid 60s along the coast. Weak shortwaves are expected
to move through the northwest flow and will bring periods of
increased cloud cover including Wednesday when models indicate
decent cloud cover to begin the day, possibly impacting
afternoon highs by a degree or two.

High pressure strengthens and begins to shift slightly westward
toward the PacNW coast, supporting an upward trend in temps
beginning Thursday. 850mb temps are expected to rise to around
10- 12 C, supporting inland temps in the low 80s and mid to
upper 60s along the coast. Friday will see a 2-4 degree drop in
temps as a short wave trough passes over the PacNW.

The warm-up is expected to ramp up into the weekend, though
there is some model discrepancies to consider. The thermal
trough will deepen and cause winds to shift to the northeast.
Overnight temperatures on Saturday into Sunday will be higher
than normal which will create a spring board for highs on
Sunday. Right now, the NBM is suggesting quite a range for highs
with the 10th percentile around 80 degrees at the Portland
Airport and similar temperatures through the Willamette Valley
and southern Washington. The 90th percentile is significantly
higher with areas breaking 100 degree mark. The coastal areas
are also seeing a 20 degree spread between the 10th- 90th
percentile, generally mid 60s to mid 80s. Confidence is still
incredibly low in regards to this system as it easily could
shift if winds stay more northerly or shift to the northwest.
However, with these kinds of pattern, we could see major Heat
Risk for portions of southwest WA and northwest OR. Will
continue to monitor though as this forecast has a lot of room to
change over the next 7 days. -Batz/Muessle

&&

.AVIATION...VFR conditions favored to continue throughout the
period inland, with northwest winds of 8-12 kt gusting to around
20 kt diminishing to 5 kt or less by 06z Tue. There are low
probabilities (10-20%) of marine stratus reaching inland and
producing MVFR cigs from 12-18z Tue. Winds will increase to 5-10
kt out of the northwest by 18z Tue beneath diurnal cu at 3-5 kft.
Along the coast, north winds of 10-15 kt gusting 20-25 kt will
weaken to 10 kt or less by 03-06z Tue as marine stratus moves into
coastal terminals, yielding MVFR cigs by 12z Tue. Skies trend
clearer after 18z Tue as winds increase to 10-15 kt, with a 30-40%
chance of lingering MVFR cigs through the afternoon.

PDX AND APPROACHES...VFR conditions favored throughout the period.
Northwest winds of 10 kt gusting near 20 kt will diminish through
the evening to 5 kt or less after 06z Tue. There are low chances
(10-20%) of MVFR marine stratus spreading inland from 12-17z Tue
with skies otherwise expected to remain largely clear. Winds
increase out of the northwest at 5-10 kt by 18z Tue. -Picard

&&

.MARINE...Not much change as a summer time pattern has settled
in with high pressure persisting offshore through the week, and
a thermally induced low pressure trough remains over the
northern California/southern Oregon coast. North to
northwesterly winds will continue across the coastal waters with
diurnally driven wind gusts easing somewhat by mid-week. Expect
wind gusts to increase again this afternoon as pressure
gradients tighten, peaking around 25-30 kt through Monday
evening. Similar conditions again Tuesday, though pressure
gradients slacken a bit. Winds continue to ease slightly mid to
late week, with wind gusts more likely peaking around 20-25 kt.
For now, have extended the Small Craft Advisory through early
Wednesday morning.

The general sea state will continued to be dominated by northerly
wind waves and a fresh northwesterly swell with significant wave
heights around 8 to 11 ft with a period of around 8-9 seconds.
Expect seas to remain steep and choppy. This will bring a chance
for Hazardous Seas criteria being met due to wave steepness,
mainly across the outer waters, through Tuesday morning. Seas
gradually subside to around 6 to 7 ft by early Wednesday.

Have also issued a Small Craft Advisory for the Columbia River Bar
from mid Monday afternoon through Monday evening for northwesterly
wind gusts up to 25 kt. -DH/TK

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for PZZ210.
     Small Craft Advisory until 2 AM PDT Wednesday for PZZ251>253-
     271>273.

&&

$$

www.weather.gov/portland

Interact with us via social media:
www.facebook.com/NWSPortland
x.com/NWSPortland