For all the doom and gloom forecasts, you would think it was going to be a blowout and washout of a weekend. Not the case at all. The bad news is that our friends in Olympia and Gig Harbor will have very light conditions all day Saturday but no rain. The Turkey Bowl will have some breeze about mid-day on Saturday before becoming light and variable for the rest of the day. Sunday will be a much better day for racing in the Center Sound with SE breeze in the 4-17 knot range all day. The most wind will be along the coast, the Strait of JdF, and Admiralty Inlet after midnight on Saturday as the post-frontal westerly comes onshore.
The surface analysis chart, sat pic, and 500MB charts for today will provide you with a very interesting picture of what is going on up and down our coast. We have centered over us today a weak 1021 MB high-pressure system hence the light air around the Salish Sea. Offshore is quite another story with a weak surface low-pressure system off Southern California that is not going very far or very fast because it is being held in place by an upper-level cutoff low-pressure system. We also have a series of low-pressure systems in the Gulf of Alaska extending as far south as 40N. The extended cold front goes from SE Alaska to almost Hawaii.
On Saturday the low off California will have drifted slowly to the north, while the lows in the Gulf of Alaska will have consolidated and will move slowly and directly towards the Pacific NW. As you can see, the pressure gradient over the Pacific NW will remain weak while the gradient behind the cold front will compress and as it comes ashore Saturday night this will bring the strong post-frontal onshore flow down the Strait of JdF.
The 48hr surface forecast is, as usual, the most interesting as it shows the entire North Pacific and this week you will see two of the deepest/strongest low-pressure systems we’ve seen this fall. The closest one to North America is currently at 982MB but in 24 hours will deepen to 968MB. Almost, but not quite, bombogenesis. That requires a 24Mb drop in 24 hours. Then off Kamchatka, Russia, and moving into the Bering Sea we have a 944MB low with hurricane-force winds on its south side. Keeping the 982MB low from directly impacting the Pacific NW is a 1032MB high off San Francisco. The 500Mb chart also shows the jet stream going over the top of this high and eventually coming ashore off the north end of Vancouver Island. This will keep us dry and with temps slightly above normal.
In this post-frontal onshore flow, the breeze will be from the NW off the coast at 30-40 knots. It will flow down the Strait at 25-35 knots, around the bottom of the Olympics, and through the Chehalis Gap at 20-30 knots. Too bad Squaxin Island and the LeMans Race couldn’t be rescheduled for Sunday. That would make for some sporty sailing especially trying to get out of Gig Harbor. The flow coming up the Sound will persist Sunday giving the Turkey Bowl some great sailing with 4-15 knots of SE most of the day with the breeze backing to the ESE then ENE late in the afternoon.
Very little rain during the daylight hours this weekend, however so far this month we’ve had just over 5” of rain compared to an average of 3.31”. For the year we are still 4.82” below average. Some rain overnight Saturday into Sunday morning and then another weak front will come into the area on Tuesday.
Enjoy the weekend!
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)