919
FXUS66 KPQR 292210
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
210 PM PST Sat Nov 29 2025

.SYNOPSIS...High pressure over the area will persist through
Sunday with a weak shortwave trough pushing southeast along the
northern edge this evening. Will see a quick shot of rain
overnight but it is not expected to widespread, and
accumulations will be light. Settled weather on Sunday and
Monday with cooler temperatures Monday morning. The next period
of active weather starts Tuesday through the end of the week
with round after round of precipitation associated with warm
fronts.

&&

.SHORT TERM...Now through Monday Night...Minimal changes to the
forecast today due to a fairly persistent pattern.
Climatologically abnormal, high pressure lingers over the area
keeping skies clear, dry, and slightly cooler. The high pressure
ridge will remain in the general area through Monday morning
though this evening a shortwave ridge will pass through the
flow. This shortwave will increase mixing and bring an influx of
moisture to the area. There is around a 30-40% chance of rain
through Sunday morning, though that is assuming the lower
elevations of the atmosphere are moist enough for the
precipitation to reach the ground. Overall, even if it does rain
no impacts are expected.

Dry conditions persist through Monday with mostly clear skies.
Winds will be lightly easterly as well which will bring in
slightly cooler air. With the clear skies and presence of cooler
air, expecting overnight temperatures to drop Sunday night into
Monday morning. Widespread minimum temperatures less than 35
degrees are expected inland, with lows in the 40s along the
coast. Probabilistically there remains a spread with the 10th
percentile (coldest solution) around 25-30 degrees in Eugene and
Corvallis, 32 degrees in Portland and along the coast, and
slightly colder in the Upper Hood River Valley and northern
Clark County. Overall, the outer rural areas have a higher
probability of freezing temperatures. These lows will quickly
rebound though through the day. Widespread frost is possible in
the interior lowlands which could accumulate on some metal
surfaces. Fog is more likely to the south where there is a 50%
chance of dense fog around Eugene.

Clouds will fill in through the afternoon as a warm front shifts
towards the area. The warm front is not overly robust and
precipitation amounts have decreased over the last several days.


.LONG TERM...Tuesday through Saturday...Rain will persist
through the day but will be light. Based on forecast soundings,
the rain could trend more towards drizzle with a very deep cloud
layer. Accumulation wise will see very little 24-hr rainfall
totals ending at 4 PM Tuesday range from 0.05-0.2 inch with the
highest accumulation along the coast and Cascades. there is a
10% chance of nearly no accumulating rain, and a 10% chance of
0.15-0.2 inch in the valley, and 0.2-0.3 inch along the coast.
Snow levels will be high.

Wednesday and Thursday will be fairly benign with no
precipitation expected as high pressure builds once again. There
is good agreement in the ensembles regarding this pattern. The
next major weather shift comes on Friday into Saturday. At this
point models are not in agreement with nearly half showing heavy
rain and others showing very little. 24 hr rainfall totals on
Saturday afternoon will be around a quarter of an inch inland, a
half inch along the coast and slightly higher accumulation in
southwest Washington. If we want to dive into the higher end
amounts (90th percentile), there is quite the range. The NBM
90th percentile is showing the 24 hour accumulation ranging from
0.6 inch in the southern Willamette Valley to 0.75 in the
northern. Nearly an inch in Longview and 1.25 inch along the
south Washington coast. Ultimately the amount of rain will be
decided upon by where the incoming low and associated warm front
align. Will note that river forecasts are showing forecast
rises on many area rivers on Saturday. The thing to note, and
this has been the scenario almost all season, is that these
systems tend to see the low pressure systems filling and thus
become less intense. -27


&&

.AVIATION...A weak front dropping southward across the region
will bring enhanced cloud cover as well as increased chances for
rain showers and lowered cigs through 12-18z Sun. MVFR cigs are
favored along the coast (60-80% chance of cigs at 3 kft or less)
and in the central/southern Willamette Valley (50-75% chance) as
the boundary progresses southward through tonight, with additional
25-45% chances for IFR cigs during the frontal passage. VFR cigs
are more likely to continue at Portland-area terminals, with only
20-30% chances for MVFR cigs. Any rain showers associated with
the front are expected to remain light and may only briefly
restrict vis at area terminals. Conditions return to VFR by 18z
Sun, except for potentially persistent low stratus or fog in the
southern Willamette Valley Sunday morning.

Winds look to remain light and variable into tonight at sites
across the region, aside from stronger easterly flow to the west
of terrain gaps. KTTD will continue to see gusty east winds
through the Columbia Gorge, while other Portland-area terminals
see lighter east winds. More widespread offshore flow turning
northerly in the Willamette Valley is expected by 09-12z Sun.

KPDX AND APPROACHES...VFR conditions favored to prevail, however
chances for MVFR cigs increase from 00-09z Sat as a weak front
drops across the region. While cigs will most likely remain near 4
kft, there are 20-30% chances for MVFR cigs instead during much
of the overnight period. Any rain showers should remain light,
with brief vis restrictions possible but prolonged impacts
unlikely. East flow at less than 10 kt will continue through the
period at KPDX, while stronger flow of 15 kt gusting to 25 kt to
the east near KTTD will ease toward the end of the period. -36

&&

.MARINE...Benign weather continues across the waters as a weak
low drops south along the coast tonight. Winds will remain less
than 10 kt while onshore flow turns offshore again and seas hold
fairly steady at 4-8 ft. High pressure building offshore into
next week will then see winds hold at 5-10 kt out of the north to
northeast through Monday night. Another boundary crossing the
waters will see winds build to 15-20 kt out of the northwest while
a long-period swell will push seas toward 10 ft on Tuesday. Winds
and seas then ease midweek with another weather system potentially
arriving late in the week. -36

&&

.BEACH HAZARDS...A long-period westerly swell is expected along
the northwestern Oregon and southwestern Washington coasts from
late Monday through Wednesday next week. Wave heights increasing
to 8 to 10 ft on Tuesday may not appear to present a safety risk
to those on area beaches, but these energetic waves will present a
moderate to high risk for sneaker waves, waves which can run
significantly farther up a beach than normal, including over rocks
and jetties. In addition, a period of perigean spring or "king"
tides means these waves will have an even easier time reaching
high up onto beaches, limiting the areas which may be safe from
wave action.

A Beach Hazards Statement has therefore been issued from 7 AM
Tuesday to 10 PM Wednesday. Sneaker waves can create potentially
life-threatening conditions in the surf zone when beachgoers can
be unexpectedly knocked off their feet and pulled out into cold
ocean waters. Caution should be used when in or near the water,
and those with children should be especially watchful. Never turn
your back on the ocean, and be sure to keep an eye on the waves.
Those participating in razor clam digs should additionally
exercise caution. -36

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...None.
&&

$$

www.weather.gov/portland

Interact with us via social media:
www.facebook.com/NWSPortland
x.com/NWSPortland