textproduct: Seattle/Tacoma

SYNOPSIS

High pressure begins to build over the area today, drying conditions out but allowing for colder overnight temperatures and likely fog development each morning into early next week. A return to a more typical pattern of lowland rain and mountain snow is expected late in the upcoming week.

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/

Current trends indicate little to no precipitation remaining across western Washington this afternoon. There will be a slight chance of precipitation along the coast and maybe portions of SW Washington this evening. Some of this could come in the form of a rain-snow mix at times, but amounts will be very light and no significant impacts are expected.

Moving forward high pressure will continue to build resulting in mainly dry conditions through Tuesday. Overnight lows will continue to hang around freezing. Otherwise, the only real impactful weather will be the potential for some morning fog/freezing fog, most notably across the south sound.

High temperatures will hang out in the low to mid 40s during this period.

LONG TERM /WEDNESDAY THROUGH SATURDAY/

There is remains some uncertainty about when the ridge will break down, but in general, sometime between Wednesday and Thursday night is most likely. Once it does, the door will be open to weather systems moving through the area bringing us fairly typical PNW weather including lowland rain, mountain snow, and occasionally breezy winds. At this time there is little signal for unusual weather through next Saturday. That said, travel across the mountains could be challenging at times due snow. -Wolcott-

AVIATION

Northwesterly flow aloft will persist through the TAF period as an upper level ridge over the northeastern Pacific builds into the area from the west. A weak system embedded in the flow aloft will move over the area tonight, bringing the potential for some light shower activity to portions of the coast and mountains. Radar this afternoon, however, indicates that lingering showers from this morning have dissipated across the area.

Conditions across the majority of the terminals this afternoon are VFR as a result, with latest satellite imagery showing clouds continuing to scatter across the Sound and coast this afternoon. VFR conditions are favored to continue through the remainder of the day with mid to high level cloud cover expected to increase across the area late this afternoon into this evening. Clearing overnight will bring the potential for fog development across the Sound and Southwest Interior with light winds and ample low level moisture. A range from MVFR to LIFR conditions will be possible for a few hours on Sunday morning for any terminals in fog.

Surface winds remain light and generally out of the north between 3-7 kt. Winds will gradually start to shift back to the south by this evening.

KSEA...VFR, with NE winds persisting at 3-7 kt. Winds will gradually shift to the SE and then S through the evening hours, remaining light. Low stratus is possible in the vicinity of the terminal between 12Z-18Z Sunday. Latest guidance shows a 60 percent chance of conditions dropping down to MVFR at the terminal and a 25 percent chance of conditions dropping down to IFR during this time.

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MARINE

High pressure will build across the coastal waters tonight and remain situated over the region into early next week. Small craft advisories remain in effect for the coastal waters through this afternoon for seas hovering around 10 ft. Seas will continue to subside towards 5-7 ft this evening and then towards 3-6 ft on Sunday, though systems passing by to the north will allow for seas to build back towards 6-9 ft again by Monday.

Dense fog may develop over portions of the area waters with clearing conditions and light winds during the overnight periods the next few days and will likely restrict visibilities at times.

The next front then looks to drop down into the area waters by late Wednesday into Thursday, which will likely bring the next round of headlines to the area waters.

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HYDROLOGY

No river flooding in the next 7 days.

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until 6 PM PST this evening for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm- Coastal Waters From Cape Flattery To James Island Out 10 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm-Grays Harbor Bar.