It's time once again to change those clocks, as daylight savings time ends on Sunday. At 2 a.m. Sunday, turn clocks backward one hour to 1 a.m.
By act of Congress, civil clocks in most areas of the United States are adjusted ahead one hour in the summer months (known as daylight time) and returned back one hour in the winter months (known as standard time). The dates marking the beginning and end of daylight time have changed as Congress has passed new statutes.
These dates were established by Congress in the Energy Policy Act of 2005.