textproduct: Seattle/Tacoma

SYNOPSIS

Upper level ridge over Western Washington through Thursday shifting east Thursday night. Dissipating front trying to move into the area later Friday into Saturday morning. Another upper level ridge builds Saturday afternoon into Sunday. Low level flow turning onshore today with varying degrees of onshore flow through most of the week.

SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/

Strong high pressure over the Pacific NW is bringing one more warm day for western Washington, especially across the interior, with temperatures in the 70s to lower 80s. The coast is cooler and in the 60s dues to NW onshore flow. Tuesday will be similar with marine clouds and cooler conditions along the coast. Temperatures in the interior will lower a few degrees but we'll still see highs in the mid to upper 70s. High pressure remains in control moving into Wednesday, leading to more dry and mild weather. Stronger onshore pushes will bring interior temps down and few more degrees with highs in the lower 70s. 33

LONG TERM /THURSDAY THROUGH MONDAY/

Dry and mild weather will extend into Thursday due to high pressure over the region. A weak front will cross the area on Friday/Friday night for a chance of rain. However, the probabilities of exceeding 0.10" of rain over the area is low or less than 10%. Most areas may only see a trace or a few hundredths if anything. Broad high pressure rebuilds over the weekend and into early next week for another dry period of weather. Interior temperatures will track a few degrees warmer than average and in the 70s. NW winds will keep the coast cooler and in the 60s. 33

AVIATION

North to northeast flow aloft continues with an upper ridge located offshore with southwesterly surface flow 5-9 kts area wide. VFR conditions will prevail across the interior this afternoon. With stronger onshore flow expected to resume overnight, expect that stratus will spread into the interior with IFR conditions expected across much of the interior lowlands on Tuesday morning. A return to VFR cigs are expected by mid to late morning, generally after 15Z.

KSEA...VFR for the rest of today and much of this evening. IFR stratus expected to return around 10Z-14Z Tuesday, breaking out more completely after 16Z. Surface wind light and variable becoming W/SW 7 to 10 knots this afternoon then light southerly tonight.

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MARINE

A thermal trough will continue shifting inland today for a return to onshore flow. Varying degrees of onshore flow will then persist through the week as a surface ridge remains anchored offshore with lower pressure inland. Small craft advisory westerlies are likely in the central/east strait each of the next several afternoons and evenings.

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HYDROLOGY

No river flooding in the next 7 days.

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until 5 AM PDT Tuesday for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca.