137
FXUS66 KPQR 181826 AAA
AFDPQR

Area Forecast Discussion...UPDATED
National Weather Service Portland OR
1124 AM PDT Wed Sep 18 2024

Updated public and aviation discussions...

.SYNOPSIS...Upper low will pass to the south today, with lingering
clouds, mainly to south and east of Salem. Otherwise, high pressure
will return, with dry weather and bit below seasonal temperatures
under variable onshore flow. Another front will bring a chance of
showers Sunday into Monday. Does appear will see warmer temperatures
next week, maybe as much model uncertainty at this time.
&&

.SHORT TERM...Now through Friday...As the day progresses, will see
the upper low sink farther to the south, with high pressure building
into Oregon. This will return dry weather with clouds gradually
giving way to partly to mostly sunny skies. Will be warmer, with
temperatures back into the 60s along the coast, and upper 60s to
lower 70s across the interior.

Not much change tonight into Friday, as will maintain high pressure
offshore. As such, will have variable light to moderate onshore flow.
Overall, rather pleasant late September weather, with patchy fog/low
clouds for overnight/early morning hours along with overnight lows
mostly in the upper 40s to lower 50s. Days will be quite pleasant,
with highs in the 60s along the coast, and lower to middle 70s
farther inland.                             -Rockey/Alviz

.LONG TERM...Saturday through Tuesday...
Forecast confidence remains below normal this weekend into the early
part of next week as model solutions continue to diverge
significantly with regard to how the upper level pattern evolves.
Ensemble clusters remain just about evenly split in depicting
ridging, troughing, and zonal flow regimes over the Pacific
Northwest from Saturday through Monday. This obviously will have
large implications for the forecast as anything ranging from
warm and dry weather to a cooler and wetter pattern remains on
the table for days 5-7. This continues to be reflected in the
NBM interquartile ranges for temperatures which range anywhere
from the upper 60s to the upper 70s between the 25th and 75th
percentile guidance. As such, and until models begin to converge
on a solution, have opted to stick with the NBM mean which
splits the difference between these solutions and depicts broad-
brushed chance to slight chance PoPs over the area late this
weekend through early next week.      /CB
&&

.AVIATION...Northeast flow aloft as upper ridge of high pressure
gradually builds over the region today. As of 18z Wednesday,
widespread MVFR CIGs are expected to gradually improve later this
morning through early afternoon, becoming predominately VFR by 20-
22z Wed. Stratus is then expected to develop again at the coast
around 03-05z Thursday with conditions likely (60-80% chance)
deteriorating to IFR tonight. Stratus also likely (60-80% chance)
builds across inland terminals after 12z Thursday with MVFR CIGs
trending toward 1500-2000 ft. Generally expect north to northwest
winds, increasing to around 10 kt this afternoon.

PDX APPROACHES...MVFR stratus has filled back in this morning with
CIGs around 1500-2500 ft. Stratus expected to break up and lift to
VFR around 20z Wed afternoon, and continue to scatter out through
this evening. MVFR stratus likely (60-70% chance) to redevelop after
12z Thursday. Expect light northwest winds to increase to around 6-8
kt by this afternoon. /DH

&&

.MARINE...High pressure returns to the coastal waters today as the
system from Tuesday departs to the south. As a result will see
northerly winds return today and continue through the week. Winds
may gust 20 to 25 kt at times, primarily over the outer zones. The
high pressure should weaken over the weekend, as will winds.

Seas around 6 ft today increasing to around 8 ft later tonight into
into Thursday, then settling to around 5 ft late in the week.
/mh

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...None.
WA...None.
PZ...Small Craft Advisory from 4 PM this afternoon to 9 PM PDT this
   evening for PZZ210.
&&



$$

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