North Cove, Washington Weather Forecast Discussion

654
FXUS66 KPQR 181037
AFDPQR
Area Forecast Discussion
National Weather Service Portland OR
337 AM PDT Thu Sep 18 2025
.SYNOPSIS...
Persistent onshore flow will maintain seasonable conditions
through the remainder of the week. A deeper trough moving in
from the Gulf of Alaska this weekend will bring a more
pronounced cool-down and an increasing chance for rain,
especially along the coast and across southwest Washington.
There is also a low potential for isolated thunderstorms in the
Cascades Friday through Sunday.
&&
.SHORT TERM...Now through Saturday...
Quiet weather will prevail through Saturday under continued
onshore flow. Minimum relative humidity values today are
expected to fall into the 40-50% range across much of the area,
with generally light winds. Gusts up to 20 mph are possible
through coastal gaps and locally into the Willamette Valley this
afternoon. Temperatures today will reach the mid to upper 70s
inland and the low to mid 60s along the coast and higher
terrain. A modest warming trend Friday and Saturday under a weak
upper-level ridge will push inland highs back toward the upper
70s to low 80s.
While overall confidence is low, there is some signal for
isolated convection in the Lane and Linn County Cascades Friday
and Saturday, with only a 5-10% probability at this time at the
crests. By Sunday, probabilities for isolated thunderstorms
broaden slightly across the forecast area (10-15%), though
confidence remains low and details are uncertain.
.LONG TERM...Saturday night through Wednesday...
Rain chances increase this weekend as a strong shortwave trough
digs southeast from the Gulf of Alaska. A cold front associated
with this system will approach late Saturday into Sunday,
bringing probabilities of measurable precipitation to 20-40%
across most of northwest Oregon. Lower probabilities (as low as
10-20%) are favored for the southern Willamette Valley and the
Lane/Linn County Cascades and foothills. The highest chances, in
the 50-80% range, are expected north and west of a line from
Willapa Hills to Tillamook, including the southwest Washington
coast and Astoria. Temperatures will trend cooler under cloud
cover and frontal passage, with highs Sunday in the low 70s
inland and 60s along the coast. Heading into early next week,
conditions remain seasonable with inland highs in the mid to
upper 70s and coastal highs in the 60s. Guidance suggests
another round of precipitation Tuesday into Wednesday as low
pressure off northern California lifts northward into a broader
trough over the northeast Pacific. Probabilities of measurable
precipitation at this time are around 20-30%, but timing and
coverage remain uncertain. ~Hall
&&
.AVIATION...Southwest flow aloft continues ahead of a weak upper
level trough. Satellite imagery shows low stratus back building
off the western slopes of the Cascades early this morning, with
KTTD reporting MVFR CIGs around FL025. Guidance suggests there is
a 30-40% that the MVFR stratus may push into other terminals
within the Willamette Valley through 16z this morning. Clear skies
as of 08z along the coast, but chances for IFR to low MVFR marine
stratus increase (50-70%) after 10z. Expect a return to
widespread VFR as low clouds scatter out by 18-19z today. Breezy
north to northwest winds again expected this afternoon at coastal
terminals with gusts up to 25 kt.
KPDX AND APPROACHES...Low stratus developing across the area as of
09z this morning. MVFR CIGs now likely around FL025 this morning
through 16z, scattering out by 18z. Then, VFR expected through
the remainder of the period with mostly clear skies. Northwest
winds 4-6 kt increase this afternoon with gusts up to 20 kt. /DH
&&
.MARINE...Gusty northerly winds continue across coastal waters
through this evening as high pressure offshore persists along with
strengthening thermal low pressure extending from northern
California into the southern Oregon coast. Expect wind gusts up
to 25-30 kt, peaking later this afternoon and evening. Buoy
observations early this morning show wave heights around 9-11 ft
with a dominant period of around 12 seconds. Expect choppy seas to
persist through tonight, as winds gradually ease by early Friday
morning. Small Craft Advisories remain in effect across all
coastal waters, including the Columbia River Bar, through this
evening. Have extended the advisory through the rest of tonight as
well for the outer waters.
High pressure shifts south on Friday as pressure gradients weaken
across the coastal waters. Northerly winds remain breezy, but
expect gusts to generally remain below 20 kt, though there is
still around a 30% chance of SCA wind gusts up to 25 kt across
the southern marine zones. A frontal system arrives this weekend
from the north, returning southerly winds later Saturday. No
substantial impacts expected for now, with guidance suggesting
around a 20% chance for southerly wind gusts up to 25 kt. /DH
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for PZZ210.
Small Craft Advisory until 5 AM PDT Friday for PZZ251>253-
     271>273.
&&
$$
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NWS pqr Office Area Forecast Discussion