Area Forecast Discussion
Issued by NWS Portland, OR
Issued by NWS Portland, OR
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168
FXUS66 KPQR 250436
AFDPQR
Area Forecast Discussion
National Weather Service Portland OR
936 PM PDT Fri Jul 24 2026
.SYNOPSIS...Onshore flow will bring near average temperatures
with varying degrees of morning clouds and afternoon sunshine
for much of the next week. A weak front will bring light rain to
portions of the coast Saturday with another weak front on
Tuesday bringing another decent chance for some light rain to
northern and coastal areas.
&&
.DISCUSSION...Now through Thursday...Overall pretty near average
temperatures for late July are anticipated over the coming
week. The coast and more northern locations will be in the
running for a couple rounds of light rain or drizzle.
A weak front will push into the region Saturday as a weak low
pressure moves northeastward towards western Washington. This
will bring with it light rain chances to mainly the coast and
Coast Range Saturday and increasing southerly winds across the
region. NBM 12-hour probabilities for measureable precipitation
are generally around 20-30% north of Waldport along the
immediate coast, but rise into the 50-60% range across the west
facing slopes of the Coast Range and Willapa Hills. The odds
that any location receives more than a tenth of an inch is
generally below 10% except across the terrain of Tillamook,
Clatsop and Pacific Counties. It will be unusually breezy with
southerly wind gusts increasing into the 25-35 mph range along
the coast.
Looking beyond the weekend, more seasonable temperatures hang
on into early next week before uncertainty increases during the
middle of the week. Cluster analysis favors the ridge slowly
building back into the PacNW which in turn would bring an
increase in afternoon high temperatures. The NBM 10th-90th
percentile reveals there`s an 80% chance each day that
temperatures end up somewhere between the upper 70s and upper
80s through the end of next week. A weak front pushing towards
and possibly into the region does appear most likely to result
in a slight dip in temperatures Tuesday into Wednesday along
with bringing another round of light rain to the north coast
although there is a notable signal in some of the global
ensemble guidance that even locations along the I5 corridor and
certainly in the Cascades north of Portland/Vancouver will
experience at least some light measurable rain on Tuesday.
&&
.AVIATION...Through 06z Sunday...Satellite imagery and surface
observations show mainly VFR conditions across the Willamette
Valley. A mix of MVFR and IFR conditions exist along the coast
as marine clouds congeal. Models are in good agreement IFR and
MVFR ceilings will by and large persist through 00-06z Sunday
along the coast. There is a 20-30% chance for MVFR ceilings at
any given hour between 12-18z Saturday as a modest southwesterly
oriented marine push brings at least some marine clouds through
the Coast Range gaps overnight spreading into the Willamette
Valley. Marine stratus coverage and timing of arrival for inland
terminals remains somewhat uncertain, but clouds are actively
pushing into the Coast Range gaps so confidence is increasing
that some MVFR ceilings will impact most, if not, all terminals
by 12-15z Saturday. What MVFR conditions come to fruition should
generally improve to VFR between 18-21z Saturday with VFR
conditions expected thereafter. Expect a period of southerly
wind gusts of 25-30 kt along the coast Saturday and 15-20 kt for
inland terminals.
KPDX AND APPROACHES...Predominately VFR through the TAF period with
a 30-40% chance for MVFR CIGs at any given hour between 12-18z
Saturday. Winds should turn southerly overnight with gusts of
15-20 kt Saturday afternoon as a weak front slides into the
region.
&&
.MARINE...Weak low pressure offshore continues to support light
south to southeasterly winds and seas of 3-5 ft. As the
aforementioned low pressure shifts northeastward towards the
Washington coast Saturday, a front will move eastward across
the waters and result in southerly wind gusts increasing into
the 23-28 kt range across the waters. In what would be pretty
exceptional for late July, there is a 10-20% chance southerly
winds at least briefly climb into the 30-35 kt range within 20NM
of the coast. Again, this does not appear likely, but it`s not
out of the question either. Current Small Craft Advisories cover
the wind hazard well at this point.
Either way, larger and steeper wind driven seas will result
with seas climbing into at least the 5-7 ft range with dominant
periods shortening into the 4-8 second range Saturday. There is
a >80% chance that the front will push ashore by 8 PM Saturday,
which will result in winds and seas subsiding across the waters
during the evening and overnight hours on Saturday.
Another weak front will approach the waters late Sunday into
early Monday with just a 25% chance that the far outer waters
beyond 40 NM north of Cape Falcon will see southerly wind gusts
at least briefly rise into the 22-25 kt range. Another front
will push towards the waters late Monday into Tuesday. While
this front stands a better chance (~50-60%) of bringing
southerly 22-25 kt wind gusts to all of the waters north of
Cape Falcon, the probability those winds extend as far south as
Cape Foulweather is just 10-20%.
Winds appear likely to return to a more typical Summertime
northerly wind pattern during the latter half of next week. Once
we get past Saturday, seas will generally be in the 3-5 ft range
for much of the next week unless some of the stronger wind
scenarios mentioned above come to fruition.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory from 11 AM to 8 PM PDT Saturday for
PZZ210.
Small Craft Advisory from 6 AM to 8 PM PDT Saturday for
PZZ251>253-271>273.
&&
$$
www.weather.gov/portland
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