Question
At 4 p.m. Friday, what better place to put on your sunglasses and go out for a walk on a warm St. Patrick’s Day?
Seattle or Los Angeles?
The surprising answer: SEATTLE!
To illustrate this amazing situation, here is Central Europe’s latest surface air temperature forecast for that time. 59F in Seattle and even higher in Chehalis and Portland.
By contrast, around 55-56F in LA on Friday afternoon.
Strolling is enhanced by dry weather. The total rainfall forecast through Saturday at 5 p.m., shown below, suggests that Seattle will be dry, with light rain in the mountains.
In contrast, during the same time period, Los Angeles will be flooded by heavy rainfall, 1-2 inches through Saturday afternoon from San Diego to Santa Barbara.
Let’s take a closer look at the upcoming warm wave, with Friday being the warmest. This is the predicted surface air temperature at 4 p.m. Friday, the warmest hour of the day.
Western Washington will be quite warm, with temperatures between 50 and under 60 degrees. Temperatures will be cooler east of Washington.
And this blessed warm day will also have a lot of sun. This is the forecast cloud model at 2 p.m. Friday. Relatively clear in Washington, but with a high cloud moving over Oregon. You don’t want to know about LA.
Why do we enjoy this warm/dry reward? By Friday afternoon there will be high pressure inland and lower pressure offshore, leading to an easterly (from east) flow through the Cascades (see below for 2 p.m. Friday). As a result, the air will be compressed (and heated) as it travels down the western slope of the fence.
I asked the machine learning app, Dalle-E, to tell me how good weather would change Seattle. Its answer is below.
