The change allows for more daylight in the afternoon but means many will lose an hour of sleep.
Hawaii and Arizona, with the exception of the Navajo Nation, don’t observe the time change.
Firefighters say the time change is a good opportunity to check and change the batteries in smoke and carbon monoxide detectors, if necessary.
Meanwhile, the Automobile Club of Southern California also warned drivers to be on the lookout for pedestrians, since it will be dark for an hour longer in the mornings.
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