Marine Weather and Tide Forecast for White Center, WA

SHORT TERM /TODAY THROUGH SUNDAY/
Weak zonal flow aloft will be replaced by upper ridging later today as the synoptic pattern amplifies in response to an upper trough digging southward offshore around 140W. The end result will be a short term warming and drying trend heading into the first portion of the upcoming holiday weekend. Residual clouds will clear away most areas by this afternoon for mostly sunny skies and temperatures similar to those of yesterday...right around climatological norms. The warming trend commences in earnest Saturday with 60s for the coast and widespread 70s for the interior lowlands from around Everett southward. The upper ridge will weaken on Sunday and onshore gradients will increase a couple notches ahead of an approaching weak front. This will put a proverbial lid on temperatures, but it should be a pretty pleasant day with dry conditions across the area. A weakening front will approach the coastal waters by Sunday evening and may spread a few showers onto the North Coast.

LONG TERM /MONDAY THROUGH THURSDAY/
A previously advertised weak upper trough and associated front will move across Western Washington on Monday with showers and high temperatures cooling back into the 60s for the lowland areas. But the upper trough doesn't stick around for long as upper ridging is expected to rebuild into the area Monday night into Tuesday. With clearing skies, temperatures should bounce back into the mid 60s to lower 70s for much of Western Washington on Tuesday. Ensembles are in fairly good agreement that the upper ridge will continue to build more strongly across the region moving into the middle of next week with 500 millibar heights potentially crossing the 580 decameter threshold and 850 millibar temperatures warming to around 16 to 18 C. So, what does that all mean? Seattle could see it's first 80 F temperatures of the year. Average first occurrence is May 20th...so only slightly behind schedule. Ensembles are split with the idea of another front trying to reach the area late next week. High amplitude upper ridging may be slow to get nudged eastward...which lends a substantial element of uncertainty to the forecast by that timeframe. 27

AVIATION
Westerly flow aloft today. Upper level trough digging south well offshore with corresponding upper level ridge building over Western Washington overnight turning the flow aloft southwesterly. Upper level ridge moves east Saturday with southwesterly flow aloft continuing. Light onshore flow in the lower levels.

VFR ceilings this morning with a broken stratus deck around 4500 feet. Local MVFR ceilings in the 2000-3000 foot range 15z-18z.
Stratus deck scattering out 18z-21z with mostly clear skies into Saturday morning.

KSEA...VFR ceilings near 4500 feet this morning. Lower ceilings could develop around 2500 feet between 15z-18z. Clouds scattering out 18z-21z with mostly clear skies for the remainder of the day into Saturday morning. Southwest wind 4 to 8 knots becoming northwest around 00z and northeast around 06z. Felton

MARINE
High pressure over the waters through Saturday with a frontal system moving inland north of Vancouver Island. The high will weaken Sunday with a weak front moving through the waters Sunday night into Monday morning. High pressure will rebuild Monday night and Tuesday. The front late in the weekend does not look strong enough to create small craft advisory conditions over the waters. Felton

SEW WATCHES/WARNINGS/ADVISORIES
WA...None.
PZ...None.