850 FXUS66 KSEW 261529 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 829 AM PDT Sun May 26 2019 .SYNOPSIS...Drier and warmer conditions are expected to start today over much of Western Washington and continue into the week ahead. Lingering moisture from an upper level low south of the area will allow for afternoon and evening showers over the Cascades most days. && .SHORT TERM /TODAY THROUGH TUESDAY/...Wrap around moisture from an upper low to the south will bring a few showers today and Monday, mainly to the Cascades. There also might be an isolated thunderstorm over the Cascades each afternoon and evening where it will be unstable. A weak upper ridge will move over the area on Tuesday. It should be a dry day expect for a slight chance of showers over the mountains in the afternoon. For today, morning low clouds should burn off but there will be mid and high clouds coming in from the east so partly sunny is probably about right. There are currently some showers drifting west from the Cascades into the metro area but these seem to be fading as they move off the mountains and it does not look like they will amount to much. Highs will be near normal today. There should be less clouds on Monday. The added sunshine will result in highs warming several degrees with lower to mid 70s for much of the interior away from the water. Stronger low level onshore flow should produce morning clouds and afternoon sunshine on Tuesday with highs cooling 3-6 degrees. Schneider .LONG TERM /WEDNESDAY THROUGH SATURDAY/...Previous discussion...Weak upper level ridging will remain the predominant weather feature for the remainder of the week yielding a generally dry pattern...however both GFS and ECMWF show occasional hints of a stray shower here or there due to disturbances associated with an upper level trough extending into eastern WA. Odds...and thus POPs...are not terribly favorable for precip...but cannot exactly leave 0 POPs either. As such...generally silent POPs of less than 10 pct are present. A weak upper level trough looks to move into the area Friday night...with both models kind of agreeing on this...and this will see a rise in POPs for near the end of the forecast period...but models do disagree on how far south the feature will plunge...and as such have gone with just slight chance POPs at this time. SMR && .AVIATION...An upper level ridge will build into northern portions of British Columbia later today. East to northeasterly flow aloft into tonight with an upper level low located well south of the area. Surface flow will be light northerly through today becoming onshore early Monday morning. Ceilings generally VFR to MVFR currently, though LIFR at KPAE with nearby vicinity fog at KHQM. Cigs will continue to improve through the morning with VFR for most by 18z-19z. Mid and high level clouds will be around into tonight. Light onshore flow late tonight into early Monday morning may lead to another round of IFR stratus early Monday, especially across the coast and into the south Sound. KSEA...Improvement to cigs this morning with MVFR becoming VFR by 18z. Some mid level clouds will be around for the afternoon. Showers will develop over the Cascades this afternoon but the flow aloft does not look strong enough to push the showers over the terminal late this afternoon into this evening. Light onshore flow will develop late tonight with IFR stratus possible Monday morning. Northerly winds 7 to 12 knots will become light late this evening. JD && .MARINE...Light northerly flow will continue through today. Surface flow will turn onshore early Monday and continue through Tuesday. A weak surface low will push into the offshore waters later Tuesday and dissipate into Wednesday. Small Craft Advisory winds likely for the central and eastern Strait of Juan de Fuca both Monday and Tuesday evening. The onshore flow could be strong enough both days for gale force winds. JD && .HYDROLOGY...The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated as needed until then. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...None. && $$ www.weather.gov/seattle
NWS SEW Office Area Forecast Discussion
Discussion Script by Ken True at Saratoga Weather - WFO Script by SE Lincoln Weather
