Cape Flattery to James Island WA out 10 to 60 NM Marine Forecast
5 - 15
5 - 15
5 - 15
5 - 15
5 - 15
20 - 25
|Today...N Wind 5 To 15 Kt. Wind Waves 1 To 2 Ft. S Swell 5 Ft At 10 Seconds.|
|Tonight...Nw Wind 5 To 15 Kt Becoming 10 To 20 Kt After Midnight. Wind Waves 1 To 3 Ft. S Swell 5 Ft At 9 Seconds.|
|Thu...W Wind 5 To 15 Kt. Wind Waves 1 To 2 Ft. Nw Swell 6 Ft At 9 Seconds. A Chance Of Showers.|
|Thu Night...Sw Wind 5 To 15 Kt. Wind Waves 1 To 2 Ft. Nw Swell 5 Ft At 9 Seconds.|
|Fri...Sw Wind 5 To 15 Kt Becoming S 15 To 25 Kt In The Afternoon. Wind Waves 2 To 4 Ft. Nw Swell 3 Ft At 8 Seconds.|
|Fri Night...S Wind 20 To 25 Kt Becoming W After Midnight. Wind Waves 3 To 5 Ft. W Swell 6 Ft At 8 Seconds.|
|Sat...W Wind 15 To 25 Kt Becoming 15 To 20 Kt. Wind Waves 3 To 5 Ft Subsiding To 2 To 3 Ft. W Swell 6 Ft.|
|Sun...W Wind 5 To 15 Kt. Wind Waves 1 To 3 Ft. W Swell 9 Ft.|
| Area Forecast Discussion|
National Weather Service Seattle WA
242am PDT Wednesday Mar 29 2023
Warm and mostly dry conditions will persist today as weak high pressure aloft nudges into the region. Conditions get cooler and wetter again from Thursday onward as a weak upper level trough moves into the region. A seasonally strong frontal system will cross the area Friday night into Saturday, with showers expected in its wake over the weekend. Upper level troughing will then persist over the Pacific Northwest into early next week, with another system slated to arrive Tuesday.
Short Term - Today through Friday
The upper level low that has been responsible for advecting some moisture and light precipitation into the southern portions of the forecast area yesterday currently resides just off the southern OR/northern CA coast early this morning. Latest radar shows showers across the local area tapering and mostly becoming confined to the southern Cascades and coastal waters at this hour. The upper level low and its associated surface reflection will continue to progress southward along the California coast today, allowing for weak upper level ridging to nudge into western Washington. Overall, expect a dry and sunny day for the majority of the area today - with the exception of a few showers remaining possible across the southern Cascades. Today is still on track to be the warmest day of the week, with high temperatures expected to climb into the upper 50s to low 60s across the lowlands.
Cloud cover will begin to advect into the area late this afternoon as a subtle shortwave trough starts to approach the region. This feature will then move into the area on Thursday. While moisture remains rather limited with this system, can still expect to see some light showers develop through the day - primarily along the coast and across any higher terrain. High temperatures on Thursday will cool a couple degrees, topping out in the upper 40s along the coast and low to mid 50s across the interior lowlands.
A more substantial shift in the weather is then on tap Friday into the weekend as a seasonally strong frontal system approaches and brings with it widespread rain and heavy mountain snow to the region. Latest guidance still hints at pre-frontal showers moving across the area Thursday night into Friday, with the more widespread rain approaching the coast Friday night and moving inland overnight into Saturday. Snow levels will fall to below pass level, so can expect periods of heavy snow to potentially yield travel impacts across the Cascade passes. At this time, winter headlines still appear likely with future forecast packages. High temperatures will be in the upper 40s to low 50s. 14
Long Term - Saturday Through Tuesday
Showery and unsettled weather is expected to persist across the region Saturday and Sunday in the wake of the aforementioned frontal system. The upper level trough influence will become greater over the weekend and conditions look to become increasingly unstable in the cooler, post-frontal airmass. Thus, can expect some shower activity to be convective - and cannot rule out some lightning potential or small hail in any of the heavier post-frontal showers. High temperatures over the weekend will primarily range in the mid 40s to near 50, with lows expected to be in the mid 30s to low 40s.
Guidance remains in good agreement with upper level troughing remaining the dominant influence across the Pacific Northwest headed into early next week. Another system then looks to drop down along British Columbia and into our area on Tuesday, bringing the potential for another round of lowland rain and mountain snow. With a cool airmass in place and snow levels remaining low, a rain/snow mix may still be possible for portions of the lowlands during the early morning hours. High temperatures will be in the upper 40s to low 50s, with overnight lows expected to be in the low to mid 30s. 14
Northerly flow prevails today then turns onshore tonight. Strongest winds will be through the Strait of Juan de Fuca where a Small Craft Advisory is in effect. The flow gradually turns southerly ahead of another frontal system that will move across the region Friday. Strong onshore flow will follow Friday night and Saturday with gales possible down the strait. 33
No river flooding is expected through the next seven days.
NOAA Seattle WA Office: Watches - Warnings - Advisories
WA...None. PZ...Small Craft Advisory from 6pm this evening to 9am PDT Thursday for
Central U.S. Waters Strait Of Juan De Fuca-
East Entrance U.S. Waters Strait Of Juan De Fuca.