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000
FXUS66 KPQR 180424 AAA
AFDPQR

Area Forecast Discussion...UPDATED
National Weather Service Portland OR
923 PM PDT Wed Apr 17 2024

Updated aviation discussion...

.SYNOPSIS...
High pressure over the region will remain through Friday,
maintaining mild sunny days and cool clear nights. Offshore flow
increases a bit for Thu and Fri, with uptick of easterly winds. Back
to cooler conditions this weekend, as a front pushes across the
region on Sat.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...High pressure is developing,
bringing warm daytime temperatures and generally clear skies
throughout the area. As a result of clear skies, temperatures
tonight cool to around the mid to upper 30s, with the
possibility of some isolated frost in the central and south
Willamette Valley only.

Thursday and Friday see slightly warmer temperatures as the
ridge settles in, with a 50-60% chance of daytime temperatures
over 70 in the entire Willamette Valley on Thursday, increasing
to 70-80% on Friday. A thermal trough begins to develop, and
offshore flow will begin picking up Thursday, particularly
through the Gorge. Gusts up to 25mph or so begin to develop in
the western Gorge Thursday morning. Friday looks gustier, with
gusts up to 35mph possible in the Gorge, slightly higher at
exposed areas at higher elevation. /JLiu

.LONG TERM...SATURDAY THROUGH TUESDAY...Models have been
consistent, and persistent, in showing a weakening front
arriving on Saturday. As such, will be cooler day, with
increasing clouds. Ensemble guidance is pointing towards QPF
being quite minimal, with only a few hundredths expected in the
Willamette Valley, and around 0.25" at the Coast Range,
Cascades, and coast. Onshore flow, with clouds and few showers
around for Sat night into Sun. Ensemble guidance shows good
agreement on a shortwave ridge moving through the area Sunday
afternoon, though uncertainty still exists on how long it`s
expected to continue. Monday looks dry, but lower certainty on
Tuesday. -Rockey/JLiu

&&

.AVIATION...VFR thresholds prevail through the entire TAF period
with clear skies as high pressure remains aloft. Northerly winds
tonight will generally be under 5 kt. Winds turn more E/NE
tomorrow as a thermal trough develops along the coast and
Willamette Valley. Winds strengthen to around 10-15 kt in the
late morning/early afternoon with gusts up to 20-25 kt at any
given terminal. Winds weaken in the evening as diurnal heating
subsides.

PDX AND APPROACHES...VFR conditions expected through the entire
TAF period. Light and variable winds tonight. Winds turn more
easterly and strengthen to around 13-17 kt after 18-19z Thu, with
gusts up to 25 kt. After 03-04z Fri, winds begin to weaken below
10 kt.-Alviz

&&

.MARINE...High pressure off the WA/B.C. coast has started to move
more onshore through the day along with a strengthening thermal
trough along the south Oregon coast will persist through Friday.
The high pressure will continue to shift inland on Thursday
shifting winds front northerly to easterly. This configuration
breaks down Friday night as a Pacific front approaches and moves
through the waters Saturday. Northerly wind gusting to 25 to 30 kt
expected for most of the waters through the evening, so a Small
Craft Advisory remains in effect for PZZ252, 253, 272, 273. The
southern and central outer waters hang onto gusty winds through
the night and into Thursday morning with the Small Craft Advisory
remaining in effect until 11 AM Thursday.

General seas through the weekend of 4 to 6 feet at 11 to 17
seconds, consisting of a long period southwest swell or a shorter
period west to northwest swell.                -Batz/mh

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for PZZ252-253.

     Small Craft Advisory until 11 AM PDT Thursday for PZZ272-273.
&&

$$

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