756
FXUS66 KPQR 010351 AAA
AFDPQR

Area Forecast Discussion...UPDATED
National Weather Service Portland OR
852 PM PDT Sat May 31 2025

Updated Aviation Discussion...

.SYNOPSIS...Slightly above normal temperatures persist through
mid-next week with no precipitation expected as a typical
spring time pattern develops.

&&

.DISCUSSION...Now through Friday...An upper level shortwave
continues to move over the PacNW while a cold front sits draped
right along the Cascades. Clouds have increased behind the cold
front, leading to mostly cloudy to overcast skies with
north/northwest winds advecting cooler air southward. Current
radar indicates light returns across southwest WA and extreme
northwest OR, leading to a few light sprinkles at the surface.
Not expecting any significant rainfall with this system given
the lack of substantial moisture and relatively dry conditions.
This pattern is also supporting an increasing pressure gradient
between Troutdale and the Dalles, with low pressure on the east
side of the Cascades and high pressure offshore building
onshore. Westerly wind gusts around Hood River could reach as
high as 40 mph with even higher gusts on the east side of the
Cascades. The gradient will weaken late this evening as the
shortwave trough axis progresses east of the Cascades. Temps
today top out in the mid 70s inland and low 60s along the coast
with very similar temps expected on Sunday.

The latter half of the weekend will see a rather stagnant
pattern set up across the PacNW. A ridge of high pressure will
sit across the northeastern Pacific while a trough covers the
Great Basin and into the central portion of the CONUS. This will
support northwest flow in the upper levels over much of WA and
OR. Temps will be consistent through mid week with mid to upper
70s expected inland and low 60s along the coast. Slight day-to-
day fluctuations will be possible as embedded shortwaves pass
overhead, bringing scattered to broken cloud cover at times.
Could see a warm up for the latter half of the week with temps
into the low 80s inland and mid to upper 60s along the coast but
confidence exact outcome is low as of now. -Batz

&&

.AVIATION...Expect current VFR conditions and clear skies to
continue through the TAF period. Northerly to northwesterly winds
will be the main concern for most of the period. Expect current
winds around 10-15 kt with gusts to 20-25 kt until 06-08Z Sunday,
then decreasing to 5-10 kt thereafter. Around 16-20Z Sunday,
winds will increase to around 15-20 kt with gusts to 28 kt along
the coast and 10-15 kt with gusts to 20 kt for inland terminals.
While most terminals will likely have gusts around 20 kt, it is
possible for some terminals to have occasional gusts up to 25 kt
(20-40% chance of gusts up to 25 kt).

PDX AND APPROACHES...VFR conditions and clear skies through the
period. Elevated northwesterly winds continue to gust up to 20 kt
until 06-08Z Sunday, then decrease to 3-7 kt thereafter. Winds
then strengthen once again around 20Z Sunday, bringing more 08-12
kt winds with gusts up to 22 kt.
~Hall

&&

.MARINE...Strong high pressure continues to build offshore over
the northeast Pacific, persisting into early next week. Pressure
gradients tighten across the coastal waters as a thermally
induced low pressure trough strengthens over northern California
into the southern Oregon coast. As a result, a period of
sustained northerlies across all coastal waters with gusts up to
25-30 kt expected through at least Sunday. Model guidance does
indicate the possibility of some isolated Gale force northerly
wind gusts Sunday afternoon and evening for the coastal waters
south of Cape Foulweather. That said, the majority of wind gusts
should stay under criteria, with only a 10% chance of Gale force
gusts. A Small Craft Advisory remains on track for all coastal
waters through Sunday, but will need to monitor trends and
conditions if any upgrades are needed through the weekend.

The current sea state as of 9 PM Saturday includes significant
wave heights around 6 to 7 ft, northerly wind waves around 6 to 7
ft with a period of 6 seconds, and a westerly swell of 2 to 3 ft
with a period of 11 seconds. The general sea state will continue
to be dominated by the northerly wind waves, with seas becoming
steep and choppy. Significant wave heights are expected to build
to around 8 to 10 ft on Sunday. This will bring low chances for
Hazardous Seas criteria being met due to wave steepness as the
period drops to around 8-9 seconds.

Pressure gradients slacken a bit on Monday, but still expect
northerlies to continue with gusts up to 25 kt. Seas likely remain
around 9 to 10 ft through Monday night before gradually subsiding
Tuesday. /DH/JLiu

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...Small Craft Advisory until 5 PM PDT Sunday for PZZ210-251>253-
     271>273.
&&


$$

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