A strong upper level ridge and offshore surface flow will give two more sunny and warm days. Record highs are likely today and wednesday. Offshore flow will weaken on thursday resulting in lower temperatures. A front will spread light rain northeast across the area on friday. There will be a chance of showers next weekend with near normal temperatures.
A shallow but very strong temperature inversion set up overnight in places exposed to easterly downslope flow. Ksea and many other slightly elevated spots in king county barely fell below 60 degrees overnight, while valley sites were in the 30s and 40s. Ksea will almost certainly set a record for highest minimum temperature today--the current record is 50. Will have to wait until midnight tonight to be sure.
Today will again be sunny and warm. Ksea was already 63 degrees at 8 am, which is the current record high temperature, so new records are sure to be set today. Offshore surface flow will keep things toasty today, and on wednesday the thermal trough is right over puget sound, meaning it will be warm in seattle again. The forecast high for both tuesday and wednesday is 75, both records. On wednesday the coast will have a bit of onshore surface flow, and highs there will be around ten degrees lower than today.
As offshore flow decreases wednesday night into thursday, expect a weak southerly surge to develop over the oregon coast and move north into the area. This will give some late night and morning stratus to the coast and portions of the interior and will result in lows dropping more uniformly into the 40s. Isolated showers or light drizzle is possible on portions of the olympic peninsula thursday morning. Burke/albrecht
Previous discussion...00z model solutions continue to show the arrival of a negative tilt frontal system friday afternoon that will be followed by a chance of showers into saturday. The ecmwf shows a minimum of shower activity on sunday as low level offshore redevelops while the gfs shows some shower activity associated with a weak upper low persisting into sunday. a model blend that is weighted toward the ecmwf was used in the forecast for now. Another negatively tilted frontal system will approach the area from the southwest monday or monday night. With the increase in clouds and moisture along with decreased offshore flow through the extended forecast period, expect temperatures to average closer to normal for late march. Albrecht
River flooding is unlikely over the next seven days.
Wa...none. Pz...small craft advisory until noon pdt today for coastal waters from james island to point grenville 10 to 60 nm-coastal waters from point grenville to cape shoalwater 10 to 60 nm- coastal waters from point grenville to cape shoalwater out 10 nm.
small craft advisory until 8 pm pdt this evening for central u.s. Waters strait of juan de fuca-coastal waters from cape flattery to james island out 10 nm-west entrance u.s. waters strait of juan de fuca.
small craft advisory until 2 pm pdt this afternoon for coastal waters from cape flattery to james island 10 to 60 nm.
Strong upper level ridge will continue over the area with persisting offshore flow. Breezy winds will continue near the gaps in coastal terrain. Strongest east winds will be at the west entrance of the strait of juan de fuca through today. Increasing winds in the central strait expected this afternoon continuing into early tonight. Light onshore flow expected on thursday ahead of a weakening front spreading into the region on friday.
Low level offshore flow will persist through today as an area of surface high pressure resides east of the cascades. The air mass will be dry and stable with southeasterly flow aloft. Vfr conditions will continue. Easterly surface winds will increase by 18z for terminals near the southern portion of the sound. Winds generally easterly today from 5 to 15 knots. Gusts up to 25 knots at ksea and khqm with offshore flow.
Ksea...easterly winds 5-15 knots this morning. Increasing offshore flow winds this afternoon will lead to gusts up to 25 knots possible. Vfr conditions continue. Jd