Bruce’s Weather Brief for May 13-14, Mother’s Day and SYC Vashon Island Race

It certainly won’t exactly be the nicest of weekends but Sunday will be the better of the two days. The problem is a very persistent upper-level low-pressure system which is just not moving very much and will keep cool, unstable air coming ashore all weekend. Take a look at the attached Langley Doppler from this afternoon and then compare it to tomorrow morning before you head out.

For now, check the current surface chart and the current 500MB chart to get a feel for what is actually going on. As you can see from tomorrow’s chart, the surface gradient will have opened up and the remains of a weakened frontal system will be approaching the coast. The really cool feature about that chart is the Pacific High which is looking very summer like. About the right pressure, 1040 MB, and in very much the right place. The only problem may be that this is a little early in the summer cycle for this to be occurring. If however, Comanche were starting TransPac tomorrow, she would absolutely blitz the record. We’ll see.

The models have come together nicely for tomorrow so we’ll roll the dice and put this out there. As always, check all your resources before you leave the house tomorrow morning. Cool, unstable air coming ashore doesn’t make for a tremendously accurate forecast.

Tidal Currents

West Point

0618      Slack

0800      Max ebb                .43 knots

1042      Slack

1606      Max flood             1.14 knots

1924      Slack

Narrows north end

0700      Slack

1118      Max ebb                3.98 knots

1430      Slack

1654      Max flood             3.95 knots

2054      Slack

There should be enough wind to allow the Vashon Island Race to start on time which is about an hour after max ebb, we still need to remember that the ebb will extend because of the amount of rain today and what will be flowing out of the Duwamish. There will probably still be a localized SE breeze at Shilshole, however at West Point it will probably be time to think about getting to the west anticipating a shift to the WSW as the day goes on.

As usual, in these conditions, it may get a bit fluky from the north end of Vashon to Pt. Robinson where, if we’re lucky, the WSW will finally start to build to 8-12 knots. You’ll want to be careful to not get too close to the Vashon shore as the wind will be coming over the Island and may not touch down until well offshore. At the bottom end of the Island stay out a ways to avoid the eastward flowing current that pretty much always run there. Get into the ebb up Colvos Passage and don’t get too close to either shore. Drivers and spinnaker trimmers will be working very hard all the way up Colvos. This will not be “Miller time”.

From the north end of Colvos to West Point, the wind will probably back from the SW to the S so you’ll need to anticipate the gybe and your approach to the finish. Watch gybing in north of West Point as this can get light from West Point to the Ship Canal.

For those of you going cruising this weekend, no real major issues of too much breeze except in the eastern end of the Straits and the San Juan Islands in the early Sunday morning hours when you should be at anchor. Just make sure you’ve got plenty of scope out and plenty of room to swing.

Have a great weekend and do something nice for mom!

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