Area Forecast Discussion
Issued by NWS Portland, OR

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182
FXUS66 KPQR 261717
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
1017 AM PDT Sun Jul 26 2026

Updated aviation discussion.

&&

.SYNOPSIS...Persistent onshore flow will bring near-average
temperatures with varying degrees of morning clouds and
afternoon sunshine for much of the next week. A series of weak
fronts will bring notable chances for light rain and drizzle to
portions of the north Oregon coast today and Tuesday.

&&

.DISCUSSION...Now through Saturday...Latest satellite water
vapor imagery highlights the features which will continue to
dictate the weather locally through the coming days: a closed
upper low near the Alaska Panhandle and an associated corridor
of enhanced baroclinicity and vorticity on its southeast flank,
currently extending from southwest to northeast over the Olympic
Peninsula and Vancouver Island. A weak frontal boundary, the
surface manifestation of the latter feature, continues to bring
light rain showers or drizzle to portions of the Washington
coast. An upper-level shortwave approaching the region today
will push this boundary to the south, bringing light rain or
drizzle chances (25-50%) to Pacific County, WA, with lower
chances (10-25%) over the adjacent Willapa Hills and north OR
coast and Coast Range. Winds rising diurnally in these areas may
see southwesterly wind gusts to 15-20 mph this afternoon, but
impacts are not anticipated. Otherwise, dry weather is expected
across the region with morning low clouds tending to mix out
this afternoon, except for more persistent cloud cover along the
coast. Seasonable high temperatures in the 60s on the coast and
in the low 80s within the Willamette Valley are expected.

As the upper shortwave exits Sunday night into Monday, heights
aloft rise somewhat, favoring drier and slightly warmer
conditions across the region. By Tuesday, another shortwave will
push the weak boundary back toward the coast, yielding light
rain chances on the coast and within coastal terrain north of
Tillamook, with the highest likelihood again in Pacific County,
WA. Reinvigorated marine cloud cover associated with the
boundary will also see temperatures cool a few degrees again on
Tuesday, before heights again rebuild aloft, favoring a slow
warming trend through the remainder of the workweek. Ensemble
members continue to highlight another chance for a shortwave and
weak surface front to support cooler temperatures and light
rain chances along the north OR/souther WA coast late in the
week, but uncertainty in the timing and placement of this
feature remains high at this lead time. -36

&&

.AVIATION...Through 18z Monday...Southwest flow aloft continues
through the TAF period. At 17z Sun, stratus remains widespread west
of the Cascades with MVFR to low-end VFR cigs. Conditions inland are
expected to improve to VFR by 18-20z Sun eventually clearing out by
mid afternoon. Along the coast, more persistent cloud cover will see
prevailing MVFR or low-end VFR cigs into this afternoon. KAST and
KONP may clear out for a period of time after 19-21z Sun, though
there`s a 20-30% chance MVFR cigs prevail through the TAF period.
There`s higher confidence in restricted cig returning by 03-06z Mon.
For inland terminals, there`s a 50-60% chance of MVFR cigs returning
to the southern Willamette Valley, including KEUG, after 10z Mon.
Elsewhere, a 20-30% chance, mainly around 12-16z Mon.

Calm to light southerly winds this morning will veer out of the
southwest to west and build to 8-12 kt along the coast and 5-10 kt
inland. Occasional gusts to 20 kt are possible along the south
WA/north OR coasts including at KAST. Winds ease below 5 kt and back
out of the south again this evening and tonight.

KPDX AND APPROACHES...MVFR to low-end VFR conditions to continue
this morning until skies trend clearer by 18-20z Sun. Light
southerly winds this morning will veer out of the west- northwest
and build to 8-10 kt by this afternoon, before easing below 5 kt and
backing out of the south again tonight. Additional 25-35% chances
for MVFR cigs after 08-10z Mon as stratus redevelops.
-03/36

&&

.MARINE...A weak surface front straddling the coastal waters
west of the mouth of the Columbia River will continue to bring
chances for light rain today, with southwest winds building to
near 15 kt with gusts to 20 kt this afternoon. Chances for gusts
of 22-25 kt remain around 50-60% beyond 30 NM off the south WA
and far northern OR coasts, however stronger gusts are expected
to be intermittent brief, most likely between 8 AM and 2 PM
today, and therefore no Small Craft hazards have been issued.
South of Cape Falcon and farther from the front, south to
southwest winds will remain lighter, 6-12 kt, with rain chances
of 15-20% or less. Seas persist at 4-6 ft with a dominant
northwesterly swell at 9-10 seconds.

Fairly benign marine conditions with southerly winds and seas of
4-6 ft are expected to continue into Tuesday, when winds will
shift to a more seasonable northerly pattern behind another
passing frontal boundary. Strengthening northerly flow will see
increasing chances (50-75%) for peak diurnal wind gusts to
reach 20-25 kt Wednesday and Thursday afternoons, especially
within 10 NM of the coast. Seas otherwise continue at 4-6 ft
through the remainder of the week. -36

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...None.

&&

$$

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