Marine Weather and Tide Forecast for Shelton, WA

SHORT TERM /TODAY THROUGH MONDAY/
Morning Update: The convergence zone from earlier this morning has dissipated. An upper level low moving across the region continues to bring generally scattered light showers. Latest radar imagery does shower a band of near stationary showers to the north of Boeing Field with moderate reflectivity. Expect localized heavier precipitation within this band. Otherwise no major updates to the forecast this morning.

A closed upper level low will gradually shift southward across Western Washington today with the focus for shower activity shifting to higher terrain of the central/south Cascades and portions of the Southwest Interior. Some areas around Puget Sound might catch a few peeks of sun this afternoon, but temperatures will remain a little below normal.

Models are latching on to a compact closed upper low slipping southward along the coast on Sunday. This system doesn't look like it will produce much of any precip, but it will ensure that we see plenty of cloud cover with temperatures continuing their recent trend of several degrees below normal for the end of June. Broad upper level ridging centered well offshore attempts to briefly nose into the area on Monday, but continued onshore flow and meager height recoveries point toward mostly cloudy and cool conditions persisting.

LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
Strong upper level ridging centered well offshore around 150W and over the eastern half of the lower 48 will keep a mean upper trough position anchored over the West Coast through much of the extended forecast period. This keeps the door open for additional upper level systems to dip southward from British Columbia maintaining below normal temperatures and producing periodic chances for showers.

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AVIATION
A mix of MVFR and VFR cigs this morning with scattered light showers as an upper level low spins over the area. The best chances for showers will be in the in the mountains (50-80% chance)and there is a 30-50% chance for Puget Sound terminals. This also comes with a 15- 25% chance for thunderstorms. The highest confidence for thunderstorms will be primarily for the southern Puget Sound (Thurston County, western Pierce County) and Lewis County where the cooler temperatures aloft associated with the center of the upper- level low supports taller storms. Improvement to VFR expected this afternoon after 18z. Another round of low clouds and MVFR cigs possible (30-40% chance) for the interior terminals and very likely (60-80% chance) for the coast this evening/tonight. Winds will be out of the south 6-10 kts this morning and gradually shift to the west through the late morning and then to the west-northwest this afternoon.

KSEA.. MVFR cigs this morning at the terminal with improvement to VFR expected after 18z. Probabilities for ceilings below 2000 feet increase to 50-80% after 09Z Sunday with a 40-50% chance of IFR cigs between 12Z-16Z Sunday. There is a slight chance (15%) for thunder Saturday afternoon, but confidence is not high enough to include it in the TAF. There is a slight chance (15%) for thunder Saturday afternoon, but confidence is not high enough to include it in the TAF. Southwesterly winds 5-9 knots will shift to the west-southwest around 21Z and then to the west-northwest between 00Z-05/06Z before shifting back to the south-southwest.

MARINE
The overall pattern over the next several days will feature a broad surface ridge centered well offshore with lower pressure across the interior promoting onshore flow. This will lead to gusty northwesterlies over the outer coastal waters and the development of steep, choppy seas later today and into early next week. In addition, the central and east Strait of Juan de Fuca will likely see diurnally driven increases in westerlies reaching small craft advisory strength on a routine basis. The offshore ridge is expected to weaken toward late next week allowing for lighter winds and subsiding seas.

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FIRE WEATHER
Little in the way of fire weather concerns remain in the picture well into the week ahead with upper troughing maintaining cool conditions, high RH, and periodic chances for shower activity.

SEW WATCHES/WARNINGS/ADVISORIES
WA...None.
PZ...Small Craft Advisory from 5 PM this afternoon to 2 AM PDT Sunday for Central U.S. Waters Strait Of Juan De Fuca- East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 2 PM this afternoon to 5 PM PDT Sunday 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.