Marine Weather and Tide Forecast for Greenwater, WA

SHORT TERM /TONIGHT THROUGH TUESDAY/
An upper level low remains centered off the shore of B.C. with a trough just offshore, and southwest flow aloft. At the surface, high pressure remains offshore with higher heights, keeping the flow cool with onshore flow providing some marine air over the region.

Much of the cloud coverage from this morning remains over the region, particularly in the Cascades and over the Olympics/Pacific Coast/South Interior. The clouds are scattering out in Puget Sound, and areas along the interior water coastline es this afternoon. The clearing will expand to most of the region through the afternoon and evening (with some clouds lingering in the mountains and the coastline). Temps this afternoon have reached the mid and upper 60s in urban areas (cools down to low 60s and 50s in the mountains and coast). The clearing will continue into the overnight/Sunday (will be the sunniest period in the forecast regionwide, and also the warmest day with highs peaking in the mid 70s in Puget Sound/South Interior).

Clouds will increase going into Monday across the region (with some clearing taking place late). By late Monday/Tuesday, a weak frontal system is expected to approach the coast. Models have been pushing the arrival of the front back a few times - it appears the best chance of showers with this front will come Tuesday for the coast (with PoPs greater ranging from 50-70%). There will still be a chance for showers further inland (20-40%), but the chance will increase going into Wednesday as the front progresses through slowly.

Temperatures will remain hold pretty steady around average through the weekend into next week (average for Seattle is 70 degrees as example). Highs will be warmest Sunday with highs approaching mid 70s in Cascade Valleys, Puget Sound and South Interior areas. This will drop down to upper 60s to low 70s Monday and Tuesday. The mountains and coastal areas will be cooler with highs peaking in the 50s to low 60s. The lows will remain in the 40s to low 50s, with the coolest lows Sunday morning.

LONG TERM /WEDNESDAY THROUGH SATURDAY/
The front from Tuesday is expected to continue inland across the region Wednesday. PoPs will increase for most remaining areas to 40-60% (with 70-80% chance up in the north Cascades). The showers are not expected to be widespread at this point (as well as amounts of precipitation), but if showers do get convective enough, they may produce some downpours/enhanced rainfall. Best chance for this is up in the north Cascades. The threat for thunder remains under 10% with this system.

Thursday's chances for PoPs are significantly lower (20-30%) and will mostly linger in the morning for any post-frontal activity.
Ensembles track the upper level low finally coming inland on Friday over Washington. This will keep the precipitation chances going through Friday into next weekend. PoPs again appear light at this point (but may change once higher resolution guidance becomes available), and thunder chances remain too low to add to the forecast at this time.

HPR

AVIATION
Scattered to overcast skies this afternoon across Western Washington terminals, with cloud cover expected to scatter out into the afternoon/evening. VFR conditions expected to persist today. Guidance hints at another round of stratus late Sunday morning (10z-19z) and potentially bringing ceilings down to MVFR.
However, uncertainty exists on how low the ceilings will get with the stratus, as there's a 20-50% chance of seeing ceilings below 3000 ft. The highest probabilities of seeing MVFR ceilings are along the coast, southwest interior, and Kitsap Peninsula at this time. In addition, this next round of stratus doesn't look to be as widespread, adding to the uncertainty of which terminals will be impacted. VFR conditions expected area-wide Sunday afternoon/evening. Surface winds will generally be northwesterly this afternoon, with winds easing overnight. Breezy conditions expected along KCLM as another round of westerlies pushes along the Strait this afternoon/evening.

KSEA...VFR conditions expected to prevail through the TAF package.
The latest guidance has backed off slightly on seeing MVFR ceilings Sunday morning, with probabilities now around 10-20%. Northwesterly flow this afternoon will become more northeasterly overnight.

29

MARINE
Broad high pressure over the northeast Pacific will remain in place through this weekend, maintaining northwesterly flow across the coastal waters. Diurnally driven pushes of westerlies down the Strait of Juan de Fuca will occur each evening with varying degrees of strength. The westerly push this afternoon/tonight will be strong and a Small Craft Advisory is currently in effect for the central and east portions of the Strait through early Sunday morning, where frequent gusts of 25-30 kt are possible.

A more active pattern begins on Monday. A weak front will traverse the waters Monday and Tuesday, with additional weak systems expected throughout the week.

Seas are expected to remain below 10 ft into next week. As for the weekend, seas will be 4 to 5 ft and will increase slightly to 5 to 7 ft on Monday, before decreasing once again to 4 to 6 ft.

29/62

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