National Weather Service United States Department of Commerce

Tracking Atmospheric River for California; Record Temperatures Further East

An atmospheric river will bring gusty to high winds, moderate to heavy rainfall, and potential flooding to California today through Saturday. Heavy snow will be possible over the Sierra Nevada mountains into Friday associated with this atmospheric river. East of these impacts dozens of record high maximum and high minimum temperatures may be broken or tied today and Friday. Read More >

The Climate Prediction Center has issued an El Niño Watch. Though conditions are currently neutral, there is a 62% chance of an El Niño developing during the May to July time period. The range of possibilities toward the end of the year includes a 40% chance of a strong El Niño to a 10% chance of no El Niño. 

El Niño is an area of above-average sea surface temperatures in the central and eastern tropical Pacific Ocean.  Over Indonesia, rainfall tends to become reduced while rainfall increases over the tropical Pacific. The low-level surface winds, which normally blow from east to west along the equator, instead weaken or, in some cases, start blowing the other direction. These changes over the tropical Pacific can effect atmospheric circulations that then translate through the atmosphere and affect weather patterns far away from the tropics.

For more information on El Niño and La Niña, see our 1-Stop El Niño/La Niña page.