This Sunday at 2 a.m., clocks “spring forward” one hour, ushering in more evening sunlight for the months ahead.
Most modern devices — including smartphones, tablets, computers, and many smart home clocks — will update automatically. However, older clocks and many vehicle clocks will need to be adjusted manually.
The practice of springing forward in the spring and falling back in the fall is overseen by the U.S. Department of Transportation and was originally intended to save energy. Daylight Saving Time (DST) was first used during World War I and World War II, but the U.S. didn’t adopt a nationwide standard until the Uniform Time Act of 1966.
In 2007, DST was expanded to cover a larger portion of the year—now about 65% of the year.
Not everyone agrees that DST saves energy. While some studies show it reduces lighting usage, increased heating and air-conditioning often offset the savings.
Hawaii, most of Arizona, and some U.S. territories do not observe Daylight Saving Time.
Public safety officials also recommend using this opportunity to replace the battery in your smoke alarm.
