186
FXUS66 KPQR 172125
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
225 PM PDT Sun May 17 2026

.SYNOPSIS...Dry and benign weather is expected across the
region through much of the next week as high pressure builds
over the Northeast Pacific, bringing a warming trend. Weak
systems aloft may bring enhanced cloud cover on some days, but
rain chances are minimal.

&&

.DISCUSSION...Now through Saturday night...Concerns for
hazardous weather are minimal through the next week. There is
high confidence that upper-level ridging and surface high
pressure will build over the Northeast Pacific, with increasing
uncertainty in the amplitude and position of the upper ridge
later in the forecast. Early in the period, while the ridge is
centered well offshore, upper shortwaves within northwesterly
flow aloft may produce enhanced cloud cover, but chances for
rainfall remain 5% or less through the middle of the week. On
clearer nights, areas of fog are most likely to develop within
sheltered valleys. As the ridge axis shifts east, temperatures
will trend upward through at least Thursday, reaching the 60s
along the coast and upper 70s to around 80 degrees along the I-5
corridor. Later in the forecast period, uncertainty in the
evolution and possible break-down of upper-level ridging
introduces a similar uncertainty in forecast temperatures. Highs
are most likely to continue in the 60s to mid 70s, but the
spread of possible outcomes becomes wider: chances of reaching
80 degrees along the I-5 corridor are generally 15-45% Friday
and Saturday, but there are also 10-25% chances of remaining
below 70 degrees. The next opportunity for widespread rain holds
off until late next weekend when there is greater consensus that
the ridge breaks down. -36

&&

.AVIATION...Mainly VFR conditions expected across the airspace
through the TAF period. Fair weather cumulus developing along
northerly flow have settled around 3500-5000 ft, maintaining low
end VFR CIGs for most terminals. Expecting more clearing through
the evening as conditions continue to dry and daytime surface
heating reduces. Chances for marine stratus pushing onshore this
evening increase to over 50% by 04-06z Monday at KAST, lower at
20% around KONP.

KPDX AND APPROACHES...Predominately VFR expected through the
period. North to northwest winds 5-8 kt expected, becoming light
and variable overnight. Could see some low stratus develop over
the eastern metro, mainly KTTD and KPDX, between 10-14z with a
20-40% chance of MVFR CIGs. -19

&&

.MARINE...High pressure offshore will shift back over the
coastal waters returning north to northwesterly winds today.
Northerlies are expected to persist through much of next week as
the summer-like pattern settles in. Strongest winds are expected
during the afternoon and evening periods as a surface thermal
trough strengthens over the southern Oregon coast. A Small Craft
Advisory is in effect for the coastal waters south of Cape
Foulweather through the early evening hours for gusts up to 25
kt. Similar conditions are expected on Monday. A series of upper
level disturbances are expected to move over the region during
the middle of the week, supporting chances for stronger winds
for all marine zones. Seas around 6-9 feet are expected into
the middle of the work week.

A Small Craft Advisory has been issued for the Columbia River
Bar in effect between 4 and 8 AM Monday morning for strong ebb
currents which will produce hazardous conditions to small
craft. Strong ebb currents are possible during the morning hours
each day this week. -19/DH

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.

WA...None.

PZ...Small Craft Advisory from 4 AM to 8 AM PDT Monday for PZZ210.

     Small Craft Advisory until 9 PM PDT this evening for PZZ253-
     273.

&&

$$

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