As I said last Friday, it’s starting to get interesting which is why we wanted to give you a heads-up about tomorrow, especially the afternoon. This will be the most wind we’ve seen so far this fall/winter so if you haven’t gotten those winter mooring lines out or taken that roller furling jib off the
The surface chart for today doesn’t show much but the forecast chart for tomorrow shows a rapidly intensifying low-pressure system coming ashore and into the Sound tomorrow afternoon. The coastal waters could see 40+ knots of southerly with higher gusts and seas in the 20’-24’ range. The eastern end of the Straits and Admiralty Inlet will see 25-35 knots of southeasterly starting early tomorrow morning and continuing through the day. By mid-morning, the south and central Sound will see 25-35 knots of southeasterly to southerly breeze with gusts near 50 knots. The stronger breeze will be to the north of Seattle. This will continue and when the front passes tomorrow afternoon, the breeze may drop a bit and clock to the southwest however as the post-frontal flow establishes itself, it will build back into the 25-35 knot range before it starts to ease in the early to mid-evening tomorrow night.
Click any image to enlarge.
December 13 500MB 
December 13 Surface Forecast 
December 14 Surface Forecast 
December 15 500MB 
December 15 Surface Forecast
The other interesting feature is the tides for this storm with the high tide in Seattle coming at 1012 and being at a height of 11.72’.The next low will be at 1705 but will only go down to 5.65’ which means for the highest winds, your mast will still be well above the breakwater height at both Elliott Bay and Shilshole.
I’ve also included the surface chart for 15 Dec because it shows a very impressive 955MB low headed towards us and yes, it does say hurricane force winds. The good news is that it will probably create more rain for us on the 17th but most of the wind impact will be felt in the coastal waters of northern BC and SE Alaska.
I’ll have another update for you tomorrow.
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)