SoCal Gas has issued an advisory urging customers to immediately reduce their natural gas use to get out in front of possible gas or electricity shortages.
The measure is meant to conserve gas supplies that are limited in the Los Angeles area by the continued closure of the company's big underground storage field near Porter Ranch. That's where a gas well broke a year ago, causing the nation's largest-ever natural gas blowout.
The company suggests lowering thermostats to 68 degrees, waiting a day to use major gas appliances like clothes dryers, and washing laundry in cold water when possible.
SoCal Gas has also warned large industrial customers they may be asked to curtail service.
Extreme cold in Southern California and throughout the Southwest has increased the risk of pipeline supply disruptions, the company said in a statement Sunday.
More than half of the electricity used in California comes from natural gas-fired power plants, which means a gas shortage could impact the electricity supply, too.
The company said the advisory will remain in effect until further notice.
This story has been updated.