Marine Weather Net

Cape Shoalwater WA to Cascade Head OR out 10 NM Marine Forecast


REST OF TODAY

SW
WINDS
5 KNOTS

TONIGHT

W
WINDS
TO 5
KNOTS

WED

N
WINDS
5 - 10
KNOTS

WED NIGHT

N
WINDS
5 - 10
KNOTS

The Marine Weather Forecast In Detail:
PZZ250 Forecast Issued: 847 AM PDT Tue Sep 13 2022

DENSE FOG ADVISORY IN EFFECT UNTIL 10 PM PDT THIS EVENING
Rest Of Today...Sw Wind 5 Kt. Wind Waves Sw 1 Ft At 4 Seconds. Nw Swell 2 Ft At 9 Seconds. Widespread Dense Fog In The Morning. Areas Of Dense Fog In The Afternoon.
Tonight...Nw Wind To 5 Kt. Wind Waves Nw 1 Ft At 4 Seconds. Nw Swell 2 Ft At 9 Seconds. Areas Of Dense Fog In The Evening. Patchy Dense Fog After Midnight.
Wed...N Wind 5 To 10 Kt. Wind Waves N 1 Ft At 4 Seconds. Nw Swell 2 Ft At 9 Seconds.
Wed Night...N Wind 5 To 10 Kt. Wind Waves N 2 Ft At 4 Seconds. Nw Swell 3 Ft At 9 Seconds.
Thu...Ne Wind To 5 Kt, Backing To Nw In The Afternoon. Wind Waves Ne 1 Ft At 4 Seconds, Shifting To The Nw At 4 Seconds In The Afternoon. Nw Swell 3 Ft At 10 Seconds.
Thu Night...Nw Wind 5 Kt. Wind Waves N 1 Ft At 4 Seconds. Nw Swell 3 Ft At 10 Seconds.
Fri...Nw Wind 5 To 10 Kt. Wind Waves 2 Ft. Nw Swell 4 Ft.
Sat...Nw Wind 5 To 10 Kt. Wind Waves 2 Ft. Nw Swell 4 Ft.
SHARE THIS PAGE:           
Area Forecast Discussion
National Weather Service Portland OR
117pm PDT Sunday September 25 2022

Synopsis
High pressure will lead to warm and dry weather through Monday, with plenty of sunshine. Temperatures will warm 10 to 15 degrees above seasonal normals, with inland valleys potentially reaching 90 degrees today and/or Monday. Nigheights will cool off nicely where the wind diminishes, thanks to the dry air mass. The next chance for rain comes midweek as a fast-moving cold front moves in from the Pacific, with a better chance of rain at end of the week.

.SHORT TERM...(Tonight through Wednesday)... KEY MESSAGES:

1) Warm and dry to start this week.

2) Cool and cloudy, with onshore flow for Wed, with spotty light showers.

High pressure over the region will maintain rather dry air mass. As such, will see typical early autumn range of temperatures, with warm (mild on coast) afternoons and somewhat cool nights. Air mass aloft does warm a bit, with 850 mb temperatures running +18 to +20 deg C, which will boost inland valleys well into the 80s again Monday. Would not be surprised to see a few spots close to 90 deg, mainly from Portland to Salem, and Hood River Valley. However, it is that time of the year, where warm afternoon temperatures do not last all that long, and temperatures drop quickly in the evening. With the dry air mass in place, temperatures will drop quickly through the 70s/60s in the evening, down to lower 50s for overnight lows.

NOAA satellite imagery still showing scattered high clouds rotating around a weak upper low, just off the south Oregon coast. This low will slowly lift northward through Monday afternoon. As such, will see some mid/high clouds drift across the region through Monday. But, no precipitation. Main effect from this low will be to increase the low level onshore flow along the coast during that time. As such, will see low clouds and patchy fog spread north along the coast tonight. Clouds will push into the Coast Range of west central Oregon, via gaps such as the Siuslaw and Alsea River valleys. If so, may see brief morning clouds in Eugene for early Monday morning.

Tuesday will be a non-descript day, with mild temperatures. With thermal trough shifting towards the Cascades, will have bit more in way of onshore flow to start the days. Similar to Monday, will see areas of morning low clouds inland. That increased marine air inland will contribute to mild temperatures inland, with most areas in the upper 70s to lower 80s for highs. Onshore flow will gradually increase through the afternoon, with locally breezy conditions for the Willamette Valley as that more dense marine air arrives.

A decaying front well offshore slowly approaching later Tuesday, and pushing inland Tuesday night into early Wednesday. Will have much stronger onshore, with locally breezy conditions over the higher terrain of the Cascades. Clouds will push inland Tuesday night, with deep marine layer in place by Wednesday morning. Clouds will persist all day, with just breaks in clouds at times for the afternoon. But, more importantly is the potential for some moisture. Will boost PoPs a bit, with showers likely for northern zones, mainly Coast Range and Willapa Hills and adjacent areas, with a chance of showers elsewhere. Deep moist marine layer and orographic lift will also promote areas of drizzle along the coast into the coastal mtns, as well as the western slopes of the Cascades/foothills. Will trend forecasts in that direction. /Rockey

Long Term
(Wednesday night through Saturday)...Onshore flow with a few showers lingers into Thursday before dry and seasonable weather develops for Friday. But, if computer models are right, will see another front arriving later Saturday, with a better chance of rain. For now, no big changes, as will trend to dry mild weather on Sat, and chance of precipitation for later Sat night and Sun. Lots of uncertainty around how the pattern evolves next weekend. Model details are remain quite fuzzy at this time, as models not in great agreement. As per national guidance, latest GFS/ECMWF (European Centre for Medium-Range Weather Forecasts) and ensemble mean consensus shows a phased upper trough approaching the West Coast by Sunday. However, recent CMC runs and the new 00Z UKMET pull off a farther southwest closed low. As such, hard to tell if will see some light rain, or actually get a solid front with decent rain on Sunday. For now, will watch how models evolve this week. But, all dry weekends are running out, as it that time of the year for rain to return more often. As such, perhaps considering getting some of those long-term outdoor projects wrapped up this week. Mother nature may be getting ready the weather to match the calendar. /Rockey

Marine
Buoy observations from early Sunday afternoon showed northerly winds around 10 to 15 kt occurring over the coastal waters, along with seas around 7 to 8 ft at 11 seconds. Observed seas were running a foot or two higher than what model guidance is suggesting, so the forecast was manually adjusted to better match observations and expected trends.

Seas should begin to fall tonight into Monday while the surface pressure gradient weakens, resulting in northerly winds around 8 to 10 kt and seas around 3 to 5 ft. Northerly winds will shift to the south on Tuesday ahead of an approaching cold front, which is set to cross the waters Tuesday night. Small craft winds are not expected with the frontal passage, however small craft seas appear likely to develop behind the front as a fresh swell builds significant wave heigheights to 10 to 12 ft on Wednesday.

It is also worth mentioning that the new moon will produce stronger tidal currents during the evening ebb cycles Tuesday through Friday. Those moving in and out of harbors and crossing coastal bars should use caution and be aware of any bar restrictions that may be in place. -TK

For information about recent marine zone changes, go online to: https://www.weather.gov/pqr/marinezone

NOAA Portland OR Office: Watches - Warnings - Advisories
OR...None. WA...None. PZ...None.