During most years there is a weather event during the third week of August that is the harbinger of the fall, when it becomes clear that the summer dry spell is over and cooler temperatures are coming.
Yes, it can still be nice, and often Septembers have spectacular periods around here, but it is not the same.
I am sitting in my home right now, listening to an unaccustomed sound....rain pattering on the roof. Take a look at the latest radar image:
Showers develop over the Olympics during the past few hours and then drifted into central Puget Sound. Its also raining on the north coast, but there isn't any radar coverage to show it (that will change next September!).
A remarkable point about this rain was that the high-resolution numerical models were predicting it well ahead of time--both the start over the Olympics and spreading downstream over central Puget Sound (see graphics). Here are the simulations from Saturday morning showing 3-h rainfall ending 5 and 8 PM:
Tomorrow, the UW WRF model is going for a convergence zone over central Puget Sound and some showers over the mountains (see graphic). The NWS models are doing pretty much the same thing.
Want to be dry? Go north or south of the convergence zone and avoid the western slopes of the Olympics and Cascades. A hike on the eastern slopes of the Cascades will be fine.
Major improvements in store for Monday and Tuesday and things go downhill on Thursday. Guess who planned on outdoor party that night? The weather gods clearly like to keep meteorologists in our place....
