Marine Weather Net

Cape Flattery to Cape Shoalwater WA between 150 and 250 NM Offshore Forecast


TODAY

W
WINDS
15 - 20
KNOTS

TONIGHT

NW
WINDS
20 - 30
KNOTS

WED

NW
WINDS
20 - 30
KNOTS

WED NIGHT

NW
WINDS
15 - 25
KNOTS

The Marine Weather Forecast In Detail:
PZZ900 Forecast Issued: 150 AM PDT Tue May 21 2024

Today...W Winds 15 To 20 Kt, Becoming Nw. Seas 5 To 8 Ft. Rain With Vsby 1 Nm Or Less.
Tonight...Nw Winds 20 To 30 Kt. Seas 8 To 12 Ft.
Wed...Nw Winds 20 To 30 Kt. Seas 8 To 13 Ft.
Wed Night...Nw Winds 15 To 25 Kt. Seas 6 To 11 Ft.
Thu...W To Nw Winds 5 To 15 Kt. Seas 5 To 7 Ft.
Thu Night...W To Nw Winds 10 To 20 Kt. Seas 4 To 7 Ft.
Fri...Nw Winds 20 To 25 Kt. Seas 6 To 10 Ft.
Fri Night...Nw Winds 20 To 25 Kt. Seas 8 To 11 Ft.
Sat...Nw Winds 15 To 25 Kt. Seas 7 To 10 Ft.
Sat Night...W Winds 10 To 15 Kt, Becoming Sw 10 To 20 Kt. Seas 6 To 8 Ft.
SHARE THIS PAGE:           
Area Forecast Discussion
National Weather Service Seattle WA
210am PDT Tuesday May 21 2024

Synopsis
A frontal system and trailing upper trough will lead to cooler and wet conditions across Western Washington today into Wednesday. Weak ridging aloft will produce drier and somewhat warmer weather on Thursday before another trough arrives Friday into Saturday for a return of cooler, unsettled conditions. A trend toward drier weather and more seasonable temperatures is possible early next week.

Short Term - Today through Thursday
Clouds are increasing across the CWA (County Warning Area) early this morning ahead of a frontal system pushing southeastward down the British Columbia coast. Rain will reach coastal areas before sunrise then spread across most of the interior by late this morning. A cold front will sweep onshore late this afternoon with rain turning to showers this evening. Quantitative Precipitation Forecast remains fairly high for late May with the much of the lowlands expected to pick up a half inch to an inch of rainfall. Post- frontal onshore flow ramps up this evening and this should get a convergence zone going for a few hours over Snohomish/King Counties.

The trailing upper trough shifts southeastward across the area during the day on Wednesday. This will keep showers and cool temperatures in the forecast across interior areas, though the focus for the precipitation should be mainly in the Cascades by Wednesday afternoon. Snow levels will dip to 3500 to 4000 feet in the Cascades, but impactful snowfall is not expected in the higher passes. Much like yesterday, upper ridging centered well offshore briefly noses in the area for drier and slightly warmer conditions on Thursday.

Long Term - Friday Through Monday
Another trough is slated to drop into the region Friday into Saturday for more showers and cool temperatures. There are signs of a shift in the synoptic pattern thereafter, but how this ultimately will play out is uncertain. Broad upper troughing over the western third of the country is expected to be replaced by a strengthening ridge early next week while a large trough takes up residence south of the Aleutians. Of course, Western Washington is caught between the two. So, it's a question of which one will have the greater influence. The latest suite of global ensembles have weakly positive height anomalies over Western Washington Sunday into Memorial Day. At a minimum, this suggests that temperatures will return to near seasonal normals by the end of the holiday weekend with best precipitation chances retreating to the Olympic Peninsula. If football is a tale of two halves, the weekend weather may be much the same. 27

Marine
Small Craft winds will continue through the Strait of Juan de Fuca through the early morning. A strong frontal system will cross the waters on Tuesday, boosting winds to SCA (Small Craft Advisory) both offshore and through the Strait of Juan de Fuca through the evening and into Wednesday. Seas will rise above 10 ft across the offshore waters by Tuesday evening and continue rise to as high as 16 ft by Wednesday especially over the northern coastal zones. Waves will be steep with short period waves dominating. Another frontal system may pass through area waters on Friday, bringing elevated seas and breezy winds.

AL

NOAA Seattle WA Office: Watches - Warnings - Advisories
WA...None. PZ...Small Craft Advisory from 8pm this evening to 5am PDT Wednesday for
Central U.S. Waters Strait Of Juan De Fuca-
East Entrance U.S. Waters Strait Of Juan De Fuca-
West Entrance USA Waters Strait Of Juan De Fuca.

Small Craft Advisory until 5am PDT early this morning for
Central U.S. Waters Strait Of Juan De Fuca-
East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 8pm this evening to 8am PDT Wednesday for
Coastal Waters From Cape Flattery To James Island Out 10 Nm-
Coastal Waters From James Island To Point Grenville Out 10 Nm-
Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm.

Small Craft Advisory from 5pm this afternoon to 11am PDT Wednesday for
Coastal Waters From Cape Flattery To James Island 10 To 60 Nm-
Coastal Waters From James Island To Point Grenville 10 To 60 Nm-
Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm.