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000
FXUS66 KPQR 151014
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
312 AM PDT Mon Apr 15 2024

.SYNOPSIS...
Onshore flow will maintain plenty of clouds and cooler temperatures
across the region for next few days, along with a few showers. High
pressure builds across region for Wed to Fri, with return of mild dry
weather. Bit more unsettled for next weekend, with more clouds and
perhaps even some showers.
&&

.SHORT TERM (TODAY THROUGH WEDNESDAY)...
A weakening upper trough is slowly pushing into the region today,
though main core of the system remains well to the north over north
Washington into southern British Columbia. Rather zonal flow aloft
off the Pacific into the Pacific NW today into tonight. System
offshore is not all that strong, and as such, will maintain some
light showers across the region today into tonight, mainly over the
higher terrain. Even so, rainfall amounts will not be all that much,
generally 0.05 to 0.20, with highest amounts over the south
Washington Cascades into the far north Oregon Cascades. Likely to see
only a trace to perhaps up to 0.05 inch for inland lowlands, such as
Vancouver/Portland area and southward to Eugene.

Onshore flow will maintain plenty of clouds today, with only partial
clearing later this afternoon though not all that confident that will
see many breaks in the clouds). Again, cooler today with highs in the
mid to upper 50s, which is what would expect for mid-April).

Overall, not a lot of change for the region for Tuesday, as will
maintain moderate onshore flow. But, do think the shower potential
will mainly be more over Washington, as well as the higher terrain
north of Tillamook to Portland to Mt Hood line. Surface ridge axis
will be shifting northward slowly during the afternoon. As such,
would expect to see clouds breaking apart, mainly over western
Oregon. Would not be surprised if Salem southward through the
Eugene/Springfield area becoming partly to mostly sunny in the
afternoon.

High pressure offshore continues to strengthen on Tuesday night into
Wednesday. Air mass will be drier Tuesday night, and with clearing
skies and light winds, temperatures will drop into the lower to
middle 30s over most of the region (away from the immediate coast).
As such, will have to monitor, as may have areas of frost later Tue
night into early Wed am. Otherwise, after a chilly start, should end
up with rather pleasant Wednesday, with sunny skies and temperatures
back 55 to 60 along the coast, and 60 to 65 for most of the interior
lowlands east of the Coast Range/Willapa Hills.   /Rockey


.LONG TERM...(THURSDAY THROUGH SATURDAY)...The ridging pattern
continues through the rest of the next workweek, with warmer
temperatures and dry conditions. Temperatures on Thursday and
Friday look to become warm again, with With a shift to offshore
flow beginning Thursday, breezy winds through the Columbia
Gorge will be possible; gusts up to 25-30mph will be possible
Thursday midday through Saturday morning.

On Saturday, while ensemble guidance is still pointing mostly
towards ridging continuing, there does appear to be the
possibly of another trough developing off west in the Pacific
Ocean. There`s a 20% chance this trough approaching close
enough to begin developing some light rain showers and cooler
temperatures. On Sunday, chance of a trough being in place
increases to around 30%.                 /JLiu

&&

.AVIATION...Low VFR stratus has developed across all sites this
morning with coastal sites fluctuating between VFR and MVFR cigs.
Fortunately, in the Portland area through the Willamette Valley
this stratus likely remains at or above 3.5kft resulting in VFR
conditions persisting. A weak front is also expected to move
across the area this morning with very sporadic light showers
possible. Going forward, low VFR are CIGS expected to lift
through Monday afternoon. Northwest winds again increase along the
coast with gusts up to 15-20 kt after 18Z today before decreasing
this evening.

PDX AND APPROACHES...Predominately VFR conditions expected
through the TAF period as stratus overhead stays at or above
3.5-4kft, gradually lifting as the day progresses. Still, there an
off chance(20-30%) for CIGS to touch MVFR conditions before 18Z
Monday. Northwest winds around 5-10 kt through the period,
strongest during afternoon and evening hours. /Schuldt
&&

.MARINE... Headed through today a cut-off low continues to push
through the Great Basin while weak ridging aloft slowly builds
overhead. Fortunately this`ll allow surface pressure gradients
over the waters to ease thus allowing winds to decrease as well. A
Small Craft Advisory remains in effect for the waters north of Cape
Falcon this morning before seas/winds finally fall below
criteria. Late Monday through Tuesday the region gets brushed by
an upper-level trough dropping into northeast Washington bringing
a 50-60% probability of Small Craft wind gusts for the outer
waters late Tuesday and Tuesday night. Towards the end of the
week, guidance continues to show a ridging pattern developing
which in turn would likely lead to continued N to NE flow at the
surface. Come Friday into the weekend seas settle around 3 to 5
feet at 13 to 15 seconds. /Schuldt
&&


.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory until 11 AM PDT Monday for PZZ210-251-271.
&&


$$


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