textproduct: Seattle/Tacoma

SYNOPSIS

The weather pattern remains fairly steady with high pressure situated offshore through the week with morning clouds and afternoon sun. Temperatures will rise a bit each day through the end of the week before beginning to cool off this weekend into early next week.

SHORT TERM /TODAY THROUGH THURSDAY/

Updated aviation discussion below. Rest of discussion remains valid at this time. 27

Upper-level pattern remaining mostly unchanged with troughing over the Great Basin and Intermountain West - a ridge remains just offshore the PNW. High clouds are currently streaming in under northwest flow aloft. Another round of patchy fog/low stratus is developing this morning but coverage won't be widespread. Low stratus/fog will give way to mid to high clouds and filtered sunshine this afternoon. A shortwave rounding the periphery of the ridge will increase slight (15-20%) PoPs, mainly across the mountains. High temperatures are forecast in the 60s across the interior with 50s along the coast. Overnight lows will fall into the 40s.

Upper-ridging is likely to maintain through Thursday as conditions remain rather benign. Temperatures are to remain near-seasonal on Wednesday but warm readily into the 70s to near 80 F across the interior on Thursday. Coastal areas will see afternoon highs in the 60s with lows in the 40s area-wide.

LONG TERM /THURSDAY NIGHT THROUGH MONDAY/

Warmer conditions will continue into Friday before more robust onshore flow move in towards the weekend. Temperatures will top out Friday into the low to mid 70s. The ridge will flatten as the pattern turns more zonal over the weekend. This should help to not just start to cool temperatures, but also bring increased chance for widespread PoPs into early next week.

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AVIATION

High pressure is anchored offshore with N/NW flow over western WA today. The low level flow remains onshore. A weak front will move inland this morning with IFR ceilings along the coast and MVFR conditions in the interior. Ceilings will gradually improve to low-end VFR this afternoon in the interior. Showers with a convergence zone possible late this afternoon and evening in the central sound. IFR to MVFR ceilings expected along the coast overnight into Wednesday morning. 33

KSEA...MVFR ceilings this morning with onshore flow. SW winds 5 to 8 kt. Clouds lifting to 4000-5000 ft this afternoon with showers in the vicinity 21-03Z. Winds turning northerly around 00-03Z.

33/Mazurkiewicz

MARINE

Onshore flow will prevail this week with high pressure offshore and lower pressure inland. Expect diurnal westerly pushes through the strait of Juan de Fuca with highest wind and waves during the late afternoon and evening hours. 33

HYDROLOGY

The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated during this time as needed.

SEW WATCHES/WARNINGS/ADVISORIES

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