Bruce’s Cinco de Mayo Weekend Weather Brief, Race to the Straits and NWISA Team Racing at Sail Sand Point

You’re probably getting tired of me pontificating about how interesting the weather has been but yesterday was truly exceptional. The team at the National Weather Service Office at Sand Point deserves a hearty well done for doing an exceptional job yesterday by getting it exactly right with just the right amount of warnings and none of the drama, just the facts. It was great to go back and forth from the computer to window and watch this event unfold.

May 4 Radar

To quantify it, in the past five years we’ve had six warnings. Yesterday we had EIGHT! I’ve attached the Doppler Radar from 1535 yesterday afternoon and it was certainly colorful and if you look closely, there are three watch boxes. In addition, at one point in the early evening when the largest system was moving over Olympia, the Doppler was showing a rainfall rate of 20.57”/hour. Impressive. CYC Seattle did the right thing keeping the fleets off the water last night. Lightning can be a woefully unpredictable critter and it was simply not worth taking a chance.

Unfortunately (or fortunately, if you’re a powerboater), we’ll pay a post-frontal price this weekend. As you can see from this mornings chart, the front is just over us and off of San Fran we have, if you’re thinking about TransPac, a nicely developing Pacific High. It’s about medium strength, however, the real key is that it is starting to round up nicely. The rounder it is, the more stable it is. The bad news would be that if we were starting TransPac tomorrow, the first three days would be a real thrash. 30-40 knots of NNW as we leave the coast. That would really sort the fleet out in a hurry. I digress.

As I was about to say, in the usual scheme of things (if there is such a thing) in the Pacific Northwest, after frontal passage the first day the ridge of high-pressure establishes itself is the best day for wind from the north. As each day passes, the amount of breeze decreases. The problem for this weekend will be that persistent trough of low pressure over southern BC which will prevent a ridge of high pressure from developing.

For the sailors, this will mean a light and variable southerly for the start of the day. A northerly will develop however the timing of that will be tough as it will depend upon the amount of clearing we have over the area. The earlier the clearing, the sooner the land will start to warm and the sooner the breeze will start filling down the Sound. In the absence of a pressure gradient, it may come down with the flood tide, the Swihart Effect. So let’s look at the tides for the weekend, which will have a profound effect on the Race to the Straits.

Admiralty Inlet Tidal Current at Bush Point

Saturday

0630      Max Ebb                 2.92 knots

1024      Slack

1248      Max Flood            1.4 knots

1524      Slack

1848      Max Ebb                 2.16 knots

 

Sunday

0712      Max Ebb                 3.12 knots

1106      Slack

1336      Max Flood            1.75 knots

1630      Slack

1942      Max ebb                2.17 knots

 

Since the RTS is a reverse start with handicaps applied at the start, the early starters on Saturday will have more positive tide but less wind. Since the northerly will fill down the west side of the Sound first, the key will be to simply use what wind there is to aim at Double Bluff, the first and only mark of the course. As you work your way to the north and you start running into flood, tend more to the west beach to get out of the tide. At Pt No Point it will be just go on across to Useless Bay and the mark at Double Bluff. The later in the day, the more wind you’ll have to deal with the flood.

The trade-off going north from Double Bluff will be to work the Whidbey Island back eddies before going across to Marrowstone where the ebb will be starting first. You would like to hit the Marrowstone shore so you can also be on the inside of the port tack lifts as you work your way towards the Marrowstone Light. After Marrowstone if you are in the ebb, watch the Cog and Sog and stay on the north side of the Midchannel Bank to stay in the ebb just don’t overstand the finish line by being swept too far to the west.

Sunday it looks like the later starters will have the advantage of both more wind and less tide. The early starters will have to fight the ebb at Marrowstone and then work their way across to the Whidbey Shore. It should be a nice sail back to the finish at Shilshole after Double Bluff remembering that the flood will start first on the west side of the Sound and be slightly stronger there. The wind will be fairly even across the Sound so the angles will be key, gybing on lifts, covering your competition and watching where the smart guys are going.

For the Lake sailors, the breeze may take a bit longer to fill at Lake Washington but it will get there. Since its Team Racing, it will be more about Team tactics than going the right way. One thing to watch for in the mornings on the Lake is that the breeze may start out from the west-northwest and from there it will clock to the north-northwest. A small change but you might be able to break a cover with it.

Have a great weekend and enjoy the improving weather.

Ed. Note: If you’ve never seen team racing, it’s amazing to watch, and you’ll be able to see it from shore at Sail Sand Point both Saturday and Sunday. Be impressed by the skills of our regional high school sailors. Also on Saturday 11-3  SSP hosts the Youth Sailing Open House put together by The Sailing Foundation. 

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