You know the spring time drill. A rainy storm passes and you expect “NW clearing winds” on the coast
and maybe at San Francisco Bay Area sites near the coast like Tomales and 3rd. Ave.
Sometimes you are disappointed because 2 storms are so close together that there is no space or time for the North Pacific High to move to the coast and for NW winds to develop.
More rarely we have “NW clearing winds” accompanied by a strong low pressure in the Great Basin and strong NW winds ≈1000 feet aloft (975MB level).
This means strong winds penetrate throughout the Bay Area even to Sherman Island.
But why are they called “NW clearing winds” and what do these look like in a satellite image? Here you go!