How propitious that the 2017 NWS Seattle Integrated Weather Team Workshop was yesterday and we got to preview what NWS is thinking about the upcoming winter and how they are going to convey this information. Love to see the Seattle office being a leader in this especially at a time when in spite of an increasingly complex weather scenario, the Trump administration wants to cut the budget of both NOAA and FEMA. As if the recent (and still unfinished) hurricane season hasn’t sent a clear enough message. Kurt is kicking my chair and telling me to get back on the job. (Ed. note: NO, he’s not!)
My, how things have changed over the last couple of weeks. We have gone from an ENSO neutral winter to a distinctly La Niña pattern which is really great news for skiers and the snowpack in the mountains. What is a La Niña pattern? In very simple terms it means that the temperature of the equatorial waters off of South America are significantly lower than normal. See the current SST anomaly chart. In an El Niño event, it’s the opposite, in other words significantly warmer than normal.
So the real question is what does this mean for boaters? As you can see from the NWS Chart of Significant Winter Weather, in La Niña years we have the greatest chance of major wind storms and lowland snow events. If you ever needed an excuse to get your furled sails down and into the sailmaker for an off-season inspection, this should be it. Also, think about getting those winter mooring lines out and figuring out how to add some extra lines. I mentioned lowland snow events because those usually accompany below normal temperatures which means winterizing your boat for below freezing temperatures. Nothing worse than walking down to the boat to find only the bridge above water. Needless to say, we’ll give you a heads-up before any of those.
Right now there is no significant weather on the radar since the front passed through this morning. The rest of the weekend looks like a typically post-frontal situation with the possibility of a Puget Sound convergence zone developing in the northern Sound and over Admiralty inlet Saturday evening.So a bit of a breezy westerly in the eastern Straits that may extend down Admiralty Inlet Saturday afternoon. The Straits could see 15-25 while the north Sound could see 15-20. Sunday will be quieter with light air in the south Sound and a nice westerly/northwesterly in the eastern Straits and north Sound. Since it’s the Pacific Northwest there may be some spotty showers around.
Click images to enlarge
The charts for the weekend also provide some interesting reading in that the 500MB charts show the upper-level lows above the jet stream and a strong upper-level high below. The chart for next week (3 Oct) also shows the jet stream coming out of the Canadian Interior and back out to us. If this were later in December or early January this would be the kind of pattern that can bring snow to the Pacific Northwest.
Have a great weekend!