An upper ridge will build over the area through monday. Low level offshore flow today will increase monday and tuesday resulting in a warming trend. Highs will peak on tuesday with record breaking temperatures likely. A weak front will dissipate before it reaches the area on wednesday. Another weakening front will arrive late in the week.
Satellite imagery and roof observation show skies have cleared over most of western washington early this morning. A few high clouds lingering over the cascades will move east of the area later this morning. Temperatures at 3 am/10z were mostly in the mid 30s to mid 40s.
The last few days of winter are going to be warm ones for western washington. Upper level ridge over the area today will continue to build tonight and monday before slowly drifting east on tuesday. Low level offshore flow already in place this morning will strengthen monday into tuesday. Cross cascade gradient which is around -2 mb this morning lowering to -6 to 8 mb by monday and to -8 to -10 mb on tuesday. Strait of juan de fuca gradients go from -1.5 mb this morning to -3 to -4 mb monday and tuesday. model 925-850 mb winds which are light this morning will turn easterly later this afternoon and tonight then increase monday afternoon into tuesday up to 15 to 20 knots. Temperatures aloft also warming with 850 mb temperatures, currently around plus 4 or 5c rising a couple of degrees today and another couple of degrees tomorrow peaking out around plus 10c monday night and tuesday. End result of all this will be a warming trend for the next three days with record breaking high temperatures by tuesday. Highs today a couple of degrees warmer than saturday, in the mid 50s to mid 60s, monday mostly in the 60s and tuesday in the 60s to lower 70s. It`s very possible with the offshore flow the coast could end up being the warmest location monday and tuesday. Lows for the next three mornings in the 30s to mid 40s with the colder low temperatures in wind sheltered locations.
Extended models in good agreement with the frontal system on wednesday breaking up before it reaches western washington. Have gone ahead and taken the chance of rain out of the forecast and raised the high temperatures by a few degrees with mostly places in the 60s. different solutions but same result on thursday. Previous model runs showed thursday as being a break in between systems. With no front on wednesday will take the slight chance pops out of the forecast for thursday. Model timing for the system on friday in better agreement on the 00z sunday run with both the gfs and ecmwf spreading rain into the interior by late friday afternoon with the front moving through the area friday night/saturday morning. cool upper level trough following the front keeping showers in the forecast for the remainder of saturday. Highs will cool thursday through saturday with mid 50s to lower 60s on thursday lowering to the normal lower to mid 50s on saturday. Lows for the most part will be in the mid 30s to mid 40s through the extended period. felton
River flooding is not expected for the next 7 days.
Light offshore flow will continue with high pressure north and east of the area, and low pressure offshore. Fronts will arrive late in the week.
Wa...none. Pz...small craft advisory for hazardous seas until 11 am pdt this morning 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.
70 degree days in march are rare in western washington. In the 75 years of records at sea-tac airport there have been only 17 days in march with a high in the 70s. Out of the 17 days, only 6 of them have occurred before the spring equinox ( 73 on 3/12/2018, 72 on 3/15 & 16/1947, 71 on 3/17/1947 and 70 on 3/18/1996 and 3/13/1979 ). Felton
Some high temperature records for monday and tuesday.
seattle olympia bellingham hoquiam quillayute
March 18th 70/1996 72/1956 68/1996 69/1996 68/1996 march 19th 63/1951 66/1988 63/1981 68/1999 66/1999
An upper level ridge will continue to build over western washington today. High clouds will thin out this morning, yielding mostly clear skies throughout the day. Patchy fog has developed in a few spots in the northern interior,near kbli. Additional fog development remains possible during the early morning hours, mainly for areas in the southwest interior. The air mass is dry and stable, with easterly flow aloft.
Ksea...vfr conditions. Light northerly winds to 5 knots, increasing to 8-11 knots this afternoon.