Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA
Issued by NWS Seattle/Tacoma, WA
587 FXUS66 KSEW 122120 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 220 PM PDT Fri Jul 12 2024 .SYNOPSIS...An upper level ridge remains over Western Washington through the weekend into next week with continued low level onshore flow. This will maintain above normal temperatures, but still notably cooler than the start of this week. No rain expected with only subtle variations in the strength of the marine pushes each night. && .SHORT TERM /TONIGHT THROUGH MONDAY/...Sunny skies continue across interior Western Washington, while low stratus has been slow to erode along the coastline. Expect these daily stratus pushes to move into the coast with temperatures closer to normal in the areas that see clouds. Meanwhile, temperatures remain above normal through the interior with temperatures warming a bit on Saturday to the upper 80s to around 90 as the onshore flow weakens. Otherwise, a rather persistent pattern remains through the start of next week. .LONG TERM /TUESDAY THROUGH FRIDAY/...The start of next week looks largely similar with decent agreement among the ensemble guidance. This will maintain onshore flow through the week and high temperatures in the mid to upper 80s through the interior. The guidance does diverge a little bit later in the week, with some of ensemble members suggesting a deeper trough over the Pacific approaches the region. This opens to door to some favorable flow to increase some convection in the Cascades as a weak front moves toward the area. Still lower confidence in this scenario with the most likely outcome is continued dry conditions, but some light precipitation for at least part of the area can`t be totally ruled out. && .AVIATION...Westerly flow aloft over W WA as zonal aloft continues. VFR persists at all area terminals this afternoon, with the exception being KHQM where marine stratus continues to create MVFR conditions. Stratus will return to coastal airfields tonight and continue through Saturday morning, with MVFR/IFR conditions. Elsewhere, VFR will persist through the period with clear skies. KSEA...VFR will continue through the TAF period. N/NW winds 5 to 10 knots will become light tonight through Saturday morning. Mazurkiewicz && .MARINE...Surface high pressure continues to be situated offshore while low pressure remains inland. A small craft advisory will continue over the outer coastal waters for increased northwesterlies. Diurnal westerlies will persist into early next week with additional headlines for the Strait. Coastal seas 6 to 8 feet this afternoon with the highest waves over the coastal waters. Seas will then decrease to 4 to 6 feet into the weekend and into early next week. Mazurkiewicz && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory until 11 AM PDT Saturday for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm- Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm. && $$