A large amount of weather has occurred and we are now in the high resolution forecast period for Monday’s lowland snow event.
The atmospheric river on Thursday/Friday did not disappoint, with some locations getting close to 10 inches of rain (see 48-hour total below). Some local rivers have reached the flood stage and large reservoirs in the area have begun to accumulate water.
Maybe it’s time for the US Drought Monitor to reduce the SEVERE drought in western Washington
😊
The warm/humid atmospheric river condition ended late Friday due to the emergence of a strong cold front moving in from the Northwest.
Behind the front, a very powerful wThe wind rises at the mouth of the river was pushed into the Juan de Fuca Strait, with winds reaching 60-70 mph, leaving tens of thousands of customers in the northern Sound region without power. Our WRF modeling system provided an excellent forecast of the wind event (see below, blue and light blue are the strongest winds).
Behind the front is cool, unstable air, pressed by the mountains, creating a lot of snow in the mountains, closing some passes for a while and causing leash requirements (see below) .
Okay… there’s been a lot of inclement and exciting weather these past few days, but what a lot of people really want to know is if there’s snow in the lowlands.
And the answer is yes…but it will only be in certain locations. Interestingly, the matter will not be cold – it will be rain!
On Monday, a strong northwesterly wind will push out of the Fraser River Valley through Bellingham and San Juans, then push into the Olympics and out of the Juan de Fuca Strait (see below, blue indicates temperature is cold enough to snow).
And by Tuesday morning, some of that cold air will hit Puget Sound (see below).
Let’s now take a look at the cumulative snowfall through Tuesday morning from the UW high-resolution model (see below). Very large numbers in the mountains (feet). A few inches from Bellingham to the San Juans. Low-level snowfall along the Juan De Fuca Strait and east or south of the Olympics….and even a few layers of snow north of Seattle.
An important factor helping to combat snow is winter downstream runoff west of the central Cascades and a general lack of precipitation as the strongest atmospheric pressure will be south of us. Will monitor developments closely.
PS: I didn’t ride my bike to work on Friday because I was afraid the wind would knock down the trees. Driving along San Point Road, I saw a giant tree branch fall around 5:45 p.m., hit a power line, create a spark, and then knock out the power. Even my house. You really have to respect and appreciate the warden/women who go out of their way to restore power.
