By Jakob Rodgers
Drought Monitor (click here)
December 10, 2021
An atmospheric river storm and a rush of cold air (click here) bore down on the Bay Area on Sunday, possibly setting the stage for drenching rain, strong winds and hail over the next couple days, and a dumping of powder several feet deep in the Sierra Nevada mountains.
San Jose and the Santa Cruz mountains were expected to encounter the brunt of the storm in the Bay Area, which was forecast to intensify late Sunday into Monday while providing the area’s first real drenching in about a month. A dusting of snow also was possible over some Bay Area peaks by Monday morning, including Mt. Tamalpais, Mt. Hamilton and parts of the Santa Cruz mountains.
To the east, the Sierra Nevada mountains were predicted to receive up to 100 inches of snow over the next couple days — a wallop that prompted travel warnings for motorists visiting in the high country.
While no drought buster, the storm promised to act as a salve for parched and quickly drying communities across the Bay Area after a month of dry, arid conditions....
By Ryan Sabalow
A satellite photo (click here) taken just before 2 p.m. Pacific time on Thursday (January 28, 2021) shows a huge vapor plume stretching from the central Pacific to the California coast.
The winter storm (click here) that could dump several feet of snow in the Sierra and soak the Sacramento Valley with rain is listed as a “strong” category “AR 3” system by the scientists who study the powerful storms that supply California with most of its water.
In 2019, the scientists who study the storms known as “atmospheric rivers” agreed to a ranking scale similar to the “Cat” system used to describe a hurricane.
An “AR 1” is the weakest system. An “AR 5” is the most destructive. The five categories the Center for Western Weather and Water Extremes at Scripps Oceanography list are “weak,” “moderate,” “strong,” “extreme,” and “exceptional."
One notorious example of an AR 5 was the New Year’s Day floods of 1997, which killed at least nine people and flooded 300 square miles of California....
