So much for the old adage that summer doesn’t start in Seattle until the 5 of July. If however, you like heat, the next two weeks are for you with this coming Monday possibly being the highest temperature ever recorded in Seattle since records were kept. Some models are showing the high on Monday being 107°F, with Portland baking at 114°F on Sunday and 113°F on Monday. The high temp for Seattle isn’t predicted to be below 80°F until the 9th of July. Darn, if only I had ordered AC last winter.
June 25 500 MB 
June 25 Surface Analysis 
June 26 Surface Forecast 
June 27 500 MB 
June 27 Surface Forecast 
June 28 Surface Forecast 
June 29 500 MB 
June 29 Surface Forecast
Today’s surface analysis chart, satellite pic, and tomorrow’s surface forecast chart show the reason for this unusual (or maybe the new norm) weather. We have a very elongated and relatively weak high-pressure system off the coast with a weak high in northern BC and two highs over central Oregon and central California. The weak (1013MB) low-pressure off of our coast isn’t moving and isn’t strong enough to push the high around. In combination with the fact that we are just a week past the Solstice, the sun is spending a lot of time heating the ground and with a lot of green foliage around to absorb this energy the air is just going to get warmer and thermal throughs will develop inland creating an offshore breeze Saturday through Monday. The offshore breeze combined with downslope compressional heating is what will create the record highs Sunday and Monday. Note also the surface forecast chart for the 26th and the 27th which show no less than six thermal low troughs over the West Coast and one that has been pushed offshore. It is going to be HOT!
As we have mentioned previously, as long as the jet stream stays south, our temperatures will remain cool. Now that the jet stream is now coming ashore near Yakutat, AK and an upper-level high-pressure system is sitting over us, temps will remain warm and these systems won’t move very much.
This will be pretty good weather for boating especially if you are a powerboater. Winds will be light except in the Eastern Straits and Central Sound on Saturday afternoon when we’ll have a westerly in the Straits and a northwesterly in the Sound. Since this is a thermally generated breeze, it will ease as the sun goes down. Sunday, the breeze will stay light in the Straits while another thermal breeze develops in the Central Sound which will bring Mother Natures’ air condioning into the areas next to the water. Areas away from the water will remain hot.
Break out the sunblock early and don’t forget that while the air is very hot, the Sound is still very cool and hypothermia can still be a killer.
Be safe and have a great weekend.
Ed. note: Our intrepid meteorologist did this report in challenging circumstances on the road. Thanks, Bruce!
Kurt grew up racing and cruising in the Midwest, and has raced Lasers since the late 1970s. Currently he is a broker at Swiftsure Yachts. He has been Assistant Editor at Sailing Magazine and a short stint as Editor of Northwest Yachting. Through Meadow Point Publishing he handles various marketing duties for smaller local companies. He currently is partners on a C&C 36 which he cruises throughout the Northwest. He’s married to the amazing Abby and is father to Ian and Gabe.