Looks like a great turnout for Winter Vashon with a nice Double-Handed Division. Unfortunately, it doesn’t look like the weather is going to cooperate.
We’ve had a spectacular week with pretty nice weather including a record high temperature. Today’s surface analysis chart shows the reason for the offshore flow we’ve had over the last couple of days with a fairly strong high-pressure system (1043mb) on the other side of the Cascades. This is an extension of the high-pressure system that brought Santa Ana winds and the Bond Fire to southern California. This high combined with a weak ridge of high pressure off the coast and the jet stream will drive the incoming storm systems to the north of us. Check out the satellite picture for today. The tail of the attached frontal system will drag over us tomorrow night with a stronger front coming in Monday night and into Tuesday morning.
December 4 500 mb 
December 4 Surface Analysis 
December 5 Surface Forecast 
December 6 500 mb 
December 6 Surface Forecast 
December 7 Surface Forecast 
December 8 500 mb 
December 8 Surface Forecast
The surface forecast charts for 48 hours, 6 Dec, gets even more interesting with the strongest low-pressure system this season showing up in the mid-Pacific. It’s round, it’s deep (942mb on Thursday) and it’s heading into SE Alaska. This system is larger than any of the hurricanes that came ashore in the US this year. Luckily, it will weaken as it gets closer to North America.
For Winter Vashon, tomorrow’s system will be just far enough to the north to not impact the racecourse. In fact, it should be sunny. It’s too bad we’re not racing in the eastern Strait of JdF where we’ll have 20-30 knots of SE breeze all day tomorrow. The gradient causing this strong SE in the Strait of JdF will ease the further south you go in Puget Sound. This will mean another light air Winter Vashon with the usual drag racing from hole to hole as you get swept north in the current in Colvos Passage. Luckily, the Race Committee has a history of shortening the course at the top end of the Island. While there may be slightly more wind when you get to the top end of the Island, as you go south, it will get lighter until about 0100 hrs Sunday morning when a 10-15 knot southerly should fill in and last until about 0900 hours when it will ease to 5-10 knots. That will last until mid-afternoon Sunday when the breeze will drop to 5 knots or less.
The South Sound just can’t buy a break, at least it won’t be raining and 34°F. Don’t forget the sunblock and it could be a little coolish as you power back to your home port so don’t forget a thermos full of the warming fluid of your choice.
Stay safe, stay healthy, and take care out there.
Bruce has raced and cruised the Pacific Northwest his entire life. He earned a Bachelor’s of Science from the University of Washington in Biological Oceanography and learned meteorology “to keep from getting kicked around on the race course.” Bruce spent nearly two decades as Associate Publisher for Northwest Yachting Magazine, retiring in mid-2015, and was the chairman of the board of trustees for the Northwest Marine Trade Association in 2014. (photo of Bruce driving Playstation is a bit dated, but cool)