165
FXUS66 KPQR 140955
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
255 AM PDT Wed May 14 2025

.SYNOPSIS...A series of weak disturbances will impact the region
through the weekend, bringing periods of light rain and slightly
below average temperatures.

&&

.DISCUSSION...Now through Tuesday...An active pattern is expected
to persist through the next 7 days with several disturbances
impacting the region. Temps will generally be slightly below
average through the weekend.

A very weak shortwave trough is expected to cross the region today,
brining with it a chance for light showers into the afternoon. Temps
peak slightly below average in the mid 60s inland and mid to upper
50s along the coast. Conditions are expected to dry out through the
day as shortwave ridging moves into the area by late afternoon. Dry
conditions continue through much of Thursday, though temps will be
around 5 degrees below average for this time of year with highs
peaking in the low 60s inland and mid 50s along the coast. Another
weak shortwave moves into the region as the shortwave ridge breaks
down Thursday evening. Another round of light rain is expected with
this disturbance. 24 hour rainfall totals from Thursday 11am to
Friday 11am are expected to be less than a tenth of an inch with
probabilities inland of 10-25% and a bit better at 25-50% along the
coast.

The active pattern is expected to continue late Friday into Saturday
as the strongest system of the week drops southward along the
British Columbia coast, digging into the PacNW coast. Rain will
still be light with this system but the probabilities for a tenth and
possibly a quarter of an inch are decent across much of the area. 24
hour probs for a tenth of an inch from 5pm Friday through 5pm
Saturday are 50-70% west of the Cascades and generally greater than
70% along the higher terrain. Probabilities for a quarter of an inch
during the same time frame are 20-40% west of the Cascades and 40-
70% for the higher terrain.

Sunday through Tuesday should be drier but model guidance does show
potential for another weak shortwave to cross the area Monday into
Tuesday. Temps during this period should increase back close to
normal, into the upper 60s by Tuesday. Model agreement decreases
further into the middle of next week with some showing a warm up
back above normal toward the 80 degree mark while others keep us in
an active, rainy pattern with slightly below temps. -Batz

&&

.AVIATION...MVFR flying conditions expected to continue at both
coastal and inland terminals through this morning as a weak
disturbance overhead exits to the south and east this afternoon.
Restricted vis within mist or haze is favored to continue through
at least 15-18z Wed along the coast, and possibly through 21-24z
Wed at KONP. Scattered light rain showers may briefly restrict vis
at area terminals, but rain chances will end by 18-21z Wed
outside of the Cascades. Skies will also trend clearer while cigs
lift toward VFR by through the afternoon. Renewed marine stratus
coverage may yield additional MVFR cigs along the coast tonight.
Northwesterly flow at 10 kt or less will persist throughout the
period along the coast, while initial southerly to southwesterly
flow around 5 kt inland veers out of the northwest at 5-10 kt this
afternoon behind the departing disturbance.

PDX AND APPROACHES...MVFR cigs and scattered light rain showers
are favored to persist through this morning, although any vis
restrictions from rain are expected to be brief. VFR conditions
return this afternoon as cloud bases lift by 18-19z Wed, and skies
trend clearer after 00z Thu. Southwest winds at 5 kt this morning
will veer out of the northwest at 5-10 kt this afternoon. -Picard

&&

.MARINE...Persistent northwest flow will steadily diminish through
Thursday morning, as seas fall from 8-10 ft early this morning to
5-7 ft by Thursday. Small Craft Advisories remain in effect
across all coastal waters through 5 AM today as winds and seas
subside, while choppy and marginally hazardous conditions may
continue within the Columbia River Bar for an additional few hours
through 9 AM today following a strong ebb current this morning.

Surface high pressure building toward the coast will see
relatively tranquil conditions continue through midweek, before a
reinvigorated northwest swell arrives with a frontal system on
Friday. Southwest flow ahead of he front will will turn again out
of the northwest in its wake, with a 20-40% chance of gale-force
gusts beyond 30 NM through the weekend. -Picard

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...Small Craft Advisory until 9 AM PDT this morning for PZZ210.

     Small Craft Advisory until 5 AM PDT early this morning for
     PZZ251>253-271>273.

&&

$$

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