Bruce’s Briefs: Wx for 10, 11, 12, and 13 Jan, Duwamish Head Race.

As you may have guessed, we are now ahead for the year in rainfall by about ¾ of an inch and snow is finally starting to pile up in the mountains. All good, now what about Duwamish Head? The answer is that it should have been run last Saturday when we had breeze all day from the SW. Tomorrow will be, as they say, interesting.

Today’s surface chart shows us a very active and interesting weather picture. The most interesting feature is that low-pressure system off of our coast with two centers and quite an array of frontal systems all aimed right at the Pacific Northwest.  The first of these strong frontal systems is going over us as this is written it will be followed by a strong onshore flow starting in the Straits tonight and then coming through the Chehalis Gap early tomorrow morning. Tomorrow’s surface forecast chart has the low-pressure center right over the Salish Sea. Sunday will see the arrival of yet another active frontal system after which high pressure will fill down from the Canadian interior bringing with it a strong Fraser outflow. This will also bring the coldest temperatures we’ve seen in quite a while early next week.

The Duwamish Head Race will be interesting because there will be plenty of wind in the Straits that will try to fill down the Sound. Unfortunately, the onshore flow coming through the Chehalis Gap will then swing to the north and these two competing winds will have to meet somewhere and that will be right over the racecourse. So there will be wind, maybe as much as 20 knots from the south for a short period of time and then the wind will come from all sorts of directions.  That will keep things interesting, it will also keep tacticians busy and foredeck crews cursing about yet another sail change. At least it won’t be snowing, yet….

Tidal currents won’t be much of an issue and with any kind of wind could be favorable.   

Tidal Current at Alki

0848      Max Ebb                 .61 knots

1218      Slack

1436      Max Flood            .53 knots

1636      Slack

2030      Max ebb                .87 knots

This would be a great weekend to check those mooring lines, open all the locker doors where there are thru-hulls and make sure there is some type of heat on the boat to keep those from freezing. Remember also that with all the rain we’ve had even if your marina is in saltwater there will be a layer of fresh water from runoff on top of the saltwater and that can freeze.

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