606
FXUS66 KPQR 181001 AAA
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
300 AM PDT Thu Jul 18 2024

.SYNOPSIS...Generally, high pressure rebuilds with above-average
temperatures through the weekend, with mostly sunny skies inland and
morning clouds along the coast. A cooling trend will likely bring
temperatures closer to seasonable normals early next week.

&&

.SHORT TERM...Today through Saturday...High pressure over the area
today resulting in dry and warm conditions. Marine stratus along the
coast is gradually pushing inland this morning, but is expected to
break up and clear for much of the area by the afternoon.
Temperatures warm back into the upper 80s to lower 90s for the
interior lowlands. Onshore flow increases this evening bringing cool
breezes. Upper shortwave trough moves over the region tonight
deepening the marine layer somewhat. Expect similar conditions for
Friday. The upper level ridge begins to rebuild on Friday, and
amplifies over the Pacific NW on Saturday. Very likely (50-70%) that
highs inland reach the mid 90s, and pushing triple digits near Hood
River. This may lead to localized areas of major HeatRisk from the
Portland metro through the Columbia River Gorge. /DH

&&

.LONG TERM...Sunday through Wednesday...Upper level ridge begins to
shift back east on Sunday. Deterministic models showing a weak upper
shortwave trough lifting north early Sunday; with it NBM showing
slight chances of showers for the coast through Sunday morning.
Temperatures inland remain warm with highs likely 85-90 degrees.
Then, cooler weather likely early next week. WPC Cluster analysis
maintains good agreement among ensemble guidance as it shows upper
level troughing sliding into the Pacific NW. How cool it gets will
depend on the location of the upper low which will be dropping down
from the Gulf of Alaska. Most guidance suggests it remains centered
north as it moves into British Columbia. Temps will likely trend
closer toward seasonal normals. Dry weather expected to continue.
/DH

&&

.AVIATION...High pressure over the region, with mild southwest
flow aloft, will maintain VFR under clear skies. Do have MVFR
marine stratus along the coast extending inland through the
valleys, with cloud tops around 2000 ft. This stratus will reach
into the south Willamette Valley, affecting areas from KS12 and
KCVO southward through KEUG and K77S until 17Z. Also, will have
areas of MVFR stratus along the Columbia River as far inland as
KPDX and KTTD early this am, as well as Cowlitz Valley. This
marine stratus will break up and dissipate, burning back to the
coast and beaches by early afternoon. Stratus will surge ashore
early this evening, with widespread MVFR CIGS along the coast.

PDX AND APPROACHES...High pressure over region keeps the ops area
under clear skies today. Areas MVFR stratus expected in/around
KPDX to KTTD as well as across Clark County from 12Z to 16Z.
/Rockey

&&

.MARINE...Weak high pressure today, with light winds. But, this
high will strengthen tonight and Friday, with increasing north to
northwest winds on the waters at that time. Still, pressure
gradients not all that tight until Sat. Should see northerly winds
gusting 20 to 25 kt on Sat and Sun. Seas mostly stay in the 3 to
5 ft range, with a mix of variable period swell.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...None.

&&

$$

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