textproduct: Seattle/Tacoma

SYNOPSIS

A weather system moving into British Columbia will brush western Washington today, bringing showers to the Pacific coast and the North Interior into Wednesday. A ridge of high pressure will rebuild over the area Thursday and Friday. Warm temperatures are expected Thursday and Friday as offshore flow develops. A weak system will move into the area on Saturday, followed by a stronger system Sunday into Monday.

SHORT TERM /TODAY THROUGH THURSDAY/

A frontal system will move into B.C. today while a weak warm front clips western WA. This front will continue to spread clouds into the region with scattered showers mainly along the coast and near the Canadian border. With the increase in clouds, we're seeing warmer temperatures this morning with upper 30s and 40s expected. Expect highs in the 50s to lower 60s.

A cold front will weaken as it shifts S/SE into western WA on Wednesday. The coast, mountains and north part will see additional showers with the highest chances of seeing wetting rains on the North Coast.

High pressure will build over the region on Thursday for dry and warmer conditions. Expect highs in the lower 70s with 60s along the water. 33

LONG TERM /THURSDAY NIGHT THROUGH MONDAY/

High pressure and offshore flow will bring one more dry and mild day on Friday. Temperatures in the interior will track a few degrees warmer with afternoon highs in the lower to mid 70s. A trough will bring cooler and wetter conditions moving into Friday night and Saturday. A stronger and wetter Pacific system will reach the area Sunday/Sunday night and into Monday. This system has potential for stronger winds along the coast with wetting rains for the coast and mountains. Mountain areas over 5000 ft may see a few inches of snow too. 33

AVIATION

Ceilings will continue to slowly lower across western Washington as mid and high-level clouds move in early this morning. Ceilings will likely remain VFR across the area through much of the day with mid-level clouds in place. A few scattered showers/locally lower ceilings will be possible along the northwestern portions of the Olympic Peninsula this afternoon with the bulk of the moisture offshore. Moisture will increase this evening and into early Wednesday morning as the system bringing these clouds moves in from the northwest. Best chances for showers will be across the northern terminals such as CLM and BLI after around 06-12Z Wed. As such, ceilings look to lower to MVFR at this time. More widespread MVFR conditions spreading across the area, including the Seattle metro, will be more likely after around 12-15Z Wed.

Winds will remain mostly light and variable, with S/SW winds up to around 5-7 kt possible this afternoon. S winds look to pick up to around 5-10 kt after around 06Z this evening.

KSEA...VFR conditions through much of the day today with increasing high and mid-level clouds this morning ahead of a frontal system offshore. Chances for MVFR cigs increase early Wednesday morning. Light S/SE winds up to 5-7 kt will turn more SW this afternoon.

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MARINE

High pressure will shift inland and to the southeast as a low pressure system moves over Vancouver Island and slowly shifts to the south. Winds will likely remain below thresholds, but some slight enhancements in the wind just off the northwest Olympic Peninsula may allow for some gusts to reach 15-20 kt Tuesday and into early Wednesday. The frontal system weakens as it moves inland on Wednesday. High pressure will then build over coastal waters Wednesday night into the end of the week. With thermal troughing along the coast, this will allow for winds to turn offshore Wednesday night into Thursday. Some enhancement in the winds will be possible in the gaps in the terrain (West Strait of Juan de Fuca, Chehalis gap/Grays Harbor area). The thermal trough looks to move inland Friday, with onshore flow increasing Friday night into the weekend as a series of systems looks to approach and move across the coastal waters this weekend into early next week.

Seas will remain around 4 to 7 feet throughout much of the week before building to 8 to 12 this weekend and remaining elevated into early next week.

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SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...None.