Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA
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Issued by NWS Seattle/Tacoma, WA
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-- Discussion containing changed information from previous version are highlighted. --826 FXUS66 KSEW 141654 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 954 AM PDT Mon Jul 14 2025 .UPDATE...-- Changed Discussion --No changes to the overall forecast. A pause in the warming trend today will resume Tuesday with widespread Moderate HeatRisk conditions expected through Wednesday. Please see the aviation and marine sections below for updates to those forecasts.-- End Changed Discussion --&& .SYNOPSIS...-- Changed Discussion --A brief reprieve in warm temperatures is expected on Monday as a system slides southward from British Columbia and skirts the area. Warmer and drier conditions will return Tuesday through Thursday, with some lowland locations potentially seeing highs in the 90s by Wednesday. Elevated fire weather conditions are also expected during this warm up. A cooling trend then commences late in the week and into next weekend.-- End Changed Discussion --&& .SHORT TERM /TODAY THROUGH WEDNESDAY/...-- Changed Discussion --A brief and somewhat respite from the heat today with stronger onshore flow and a trough moving down from B.C. Interior temps are forecast in the 70s today or closer to average. The coast will remain cooler and in the 60s with northwest winds. Showers with the trough are mostly north of the border and east of the crest. The heat is back on Tuesday and Wednesday as heights rebuild, with the ridge now centered offshore near 140W, and a thermal trough forming over the region. Highs in the interior will reach the 80s to low 90s on Tuesday, with widespread 90s on Wednesday - leading to Moderate HeatRisk. At the coast, the beaches will be in the 60s with 70s-80s a few miles inland. Winds aloft on Tuesday will turn more N/NE which may bring Canadian wildfire smoke into western WA. Per HRRR smoke forecasts, the smoke concentrations look to be mainly aloft. The flow will turn westerly on Wednesday for less smoke intrusion over the westside. 33-- End Changed Discussion --&& .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...-- Changed Discussion --Weak onshore pushes will bring cooler conditions to the coast Thursday-Friday, but temperatures in the interior will remain warm and in the 80s. A stronger push this weekend looks to finally brings temps back to normal. No precip in sight. 33-- End Changed Discussion --&& .AVIATION...-- Changed Discussion --Northwest to northerly flow aloft as an upper level ridge remains offshore. VFR conditions at most terminals this morning as stratus wasn`t as expansive than initially forecast. But, stratus remains along the coast and parts of the interior and should linger until 18z (with the exception of KHQM). Northerly surface winds this morning turning somewhat southwesterly this afternoon. Winds will turn back northerly tonight and lighten. KSEA...VFR this morning and into the day. N winds this morning around 3 to 6 kt. Winds will gradually lessen early this afternoon as winds turn southwesterly for a couple of hours. Northerly winds will return around 00z between 5 to 10 kt. McMillian-- End Changed Discussion --&& .MARINE...-- Changed Discussion --High pressure remains offshore giving way to light onshore flow across the area waters. Diurnally driven westerly pushes down the strait will continue over the next several days with various strengths. A Small Craft Advisory will continue for the coastal waters for elevated winds and steep seas. Thermal troughing looks to build along the coast through midweek, with periodic increases of northerly winds through the area waters. Coastal seas 8 to 10 feet and will generally remain through the first half of the week. McMillian-- End Changed Discussion --&& .FIRE WEATHER...-- Changed Discussion --A passing disturbance will bring a brief relief today from the very warm and dry conditions of the weekend. This system will bring much stronger onshore flow, spreading widespread clouds and cooler conditions. However, attention will then turn to the return of high pressure over the region. Expect to see afternoon RH values dip down close to critical thresholds Tuesday afternoon with a thermal trough building north over the Cascades. While some uncertainty remains with respect to how far north and west this builds, expect to see at least some east component to the surface winds near the Cascade gaps in zone 659 and perhaps portions of 657 and 658. Confidence is lower in seeing more widespread easterly wind and speeds may not be strong enough to raise fire weather concerns to critical, but this may serve to further reduce RHs. Additionally, depending on the placement of the thermal trough, expect to see a deeper mixed layer and increased instability with mixing heights potentially rising into Wednesday. While confidence in the specific timing of elevated fire weather concerns is still lower, the mid week period bears close watching for both existing incidents and for the potential for conditions to remain of concern if new ones were to begin. Looking ahead to the end of the week, expect conditions to remain warmer and drier than normal but forecast guidance continues to exhibit a large range of potential scenarios that leave confidence lower than normal. Cullen-- End Changed Discussion --&& .HYDROLOGY... && .SEW WATCHES/WARNINGS/ADVISORIES...-- Changed Discussion --WA...Heat Advisory from noon Tuesday to 10 PM PDT Wednesday for City of Seattle-Downtown Everett / Marysville Area- Eastern Kitsap County-Eastside-Foothills and Valleys of Central King County-Foothills and Valleys of Pierce and Southern King Counties-Foothills and Valleys of Snohomish and Northern King Counties-Foothills and Valleys of Thurston and Lewis Counties-Foothills and Valleys of the North Cascades-Lowlands of Lewis and Southern Thurston Counties-Lowlands of Pierce and Southern King Counties- Lowlands of Western Skagit and Northwestern Snohomish Counties-Lowlands of Western Whatcom County-Middle Chehalis River Valley-Northern Hood Canal-Olympia and Southern Puget Sound-Shoreline / Lynnwood / South Everett Area-Southern Hood Canal. PZ...Small Craft Advisory until 5 PM PDT this afternoon for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm- Coastal Waters From Cape Flattery To James Island Out 10 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm.-- End Changed Discussion --&& $$