01.17.10
It Never Rains in California…
The jet stream has recently shifted from its meridional (north-south) pattern to more of a zonal (west-east) pattern, preventing the cold air up in Canada from diving south and allowing much of the U.S. to warm up a bit.
This weather pattern also means more coastal storms for the West Coast, especially California.
Take a look at the following radar image of southern California this evening (6:38 pm Pacific Time).
Now look at the following infrared satellite image over the Pacific Ocean, showing a few more storm systems (extratropical cyclones) heading eastward.
How much rain may be in store for the coast? The Hydrometeorological Prediction Center (HPC) is predicting just over 11 inches between Los Angeles and San Diego just from tonight through Friday night (below)! Shortwave troughs embedded within the flow of the jet stream are responsible for much of the expected rain (and snow in the mountains). Upper-level divergence is found downstream of a trough, causing and/or enhancing upward motion and the development of low-level convergence (hence a surface low pressure system). These shortwaves are also going to bring thunderstorms (potentially severe!) to eastern Texas on Wednesday.
Albert Hammond was right when he sang, “It never rains in California, but girl don’t they warn ya. It pours, man it pours.”