Pineapple Express Helps to Alleviate California Drought

Portions of the western United States are in desperate need of rainfall but January offered little to no drought relief in California. Check out this map illustrating radar-estimated rainfall totals during the month of January. Areas shaded in green and blue saw less than two inches of monthly rainfall.

If you thought the Bowling Green bubble was bad, check out the area with no observed precipitation in central California. There were many locations near San Francisco that saw no rainfall the entire month.

With very little rain, the drought continues in California. The last release from the U.S. Drought Monitor on January 27 classifies 94.34% of the state in at least a severe drought with 39.99% of the state in an exceptional drought.

Drought impacts are affecting just about everyone in state, including ski resorts who are dealing with a lack of snowpack in the mountains of California.

Fortunately, portions of northern California will see some rainfall chances beginning tomorrow thanks to the Pineapple Express. This term is not a reference to the popular movie as the Pineapple Express is actually a term that describes a typical wintertime pattern in the Pacific where the subtropical jet stream pulls moisture from the Pacific Ocean to the western United States.

This stream of moisture is often referred to as an atmospheric river. Atmospheric rivers can be detected by looking at the amount of moisture in a column of air.

The Pineapple Express will bring much needed rain to portions of central and northern California beginning tomorrow. Flash flood watches are in effect for areas north of San Francisco as 3-6″ of rainfall is expected by Sunday with higher upslope totals.

Unfortunately, southern California will miss out on this batch of precipitation and the drought will not be alleviated in these locations.