Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA
Issued by NWS Seattle/Tacoma, WA
368 FXUS66 KSEW 242223 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 323 PM PDT Tue Sep 24 2024 .SYNOPSIS...A weather system will move across the region on Wednesday, bringing more widespread rain, breezy winds, and a chance of isolated thunderstorms to the area. Another system will move into the region Thursday night into Friday, before conditions dry out over the weekend. && .SHORT TERM /TONIGHT THROUGH FRIDAY/...Temperatures rebounded nicely today after widespread morning fog. Highs are mainly in the 70s this afternoon with 60s near the water. Expect a quiet night tonight with increasing clouds and lows in the 50s. Wednesday brings more fall-like weather as the ridge exits east and a trough moves inland. Temps will be back in the 60s and cooler than normal. We may see a little light prefrontal precip during the morning, then rain increasing through the afternoon as the main frontal band moves in. The air mass is slightly unstable over and near the Cascades where isolated thunderstorms are possible. Showers will shift toward the King/Snohomish line during the evening with a strong onshore push and setup for a Puget Sound convergence zone. We`ll see a brief break on Thursday, then more rain and wind moving through the region heading into Thursday night and early Friday. Again, more widespread rainfall amounts for the whole region with wetting rains in the mountains. Winds will be breezy overnight Thursday along the North Coast and North Interior with S gusts to 30-40 MPH. 33 .LONG TERM /SATURDAY THROUGH TUESDAY/...The weekend forecast, for now, is looking cool but quiet with weak troughing over the region. Not much moisture or forcing over the region with generally dry conditions. Highs will reach the lower to mid 60s with lows in the 40s and 50s. Broad high pressure covers the Pac NW moving into early next week, keeping the weather mild. Rain returns Monday night or Tuesday as the ridge pushes east. 33 && .AVIATION...Skies have cleared to widespread VFR conditions with a few low clouds lingering over the Strait of Juan de Fuca and some mid to high clouds streaming into the north. MFR to IFR ceilings expected to return to area terminals this evening along the coast then through the interior after 06/07Z. Light north/northeast low level winds will gradually back to the south to southwest across the area after 06z this evening ahead of approaching frontal system. This system will bring light rain to the area Wednesday with breezy to gusty winds. KSEA...VFR conditions will linger into the early morning with stratus expected to redevelop 9/10Z - 1500 to 2500 feet, with a 70% chance of ceilings below 1000 feet after 12Z. Northerly surface winds 4-6 knots will return to southerly late tonight building to 8- 10 kt by late morning. Light rain should move into the terminal by 19Z. && .MARINE...Surface high pressure will linger over the coastal waters this evening with northerly/onshore winds and seas over the coastal waters generally 7 to 9 ft. A relatively strong frontal system on track to bring backing winds to south-southwest late tonight into Wednesday followed by northwest winds behind the front. The resulting push of westerlies through Strait of Juan de Fuca is expected to bring small craft winds, 20 to 30 kt, with around a 20 percent chance of gusts hitting 34 knots or greater. Seas are expected to come up a bit to 9 to 10 ft with this front as well. Another, what continues to look stronger, front is expected to follow on the heels of the first - moving into area waters late Thursday. This will bring another round of stronger winds with a higher likelihood of gusty southeasterlies ahead of the front followed by another strong push through the Strait of Juan de Fuca during the afternoon and evening hours. Seas are expected to build further with this system - into the 13 to 16 ft range over the outer coastal waters Friday. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...None. && $$