Overview
- The switch occurs at 2:00 a.m. local time on Sunday, November 2, when clocks move back one hour to start standard time.
- The change applies in 48 of 50 U.S. states, including Chicago, where daylight will shift earlier in the morning and end earlier in the afternoon.
- Mexico will adopt winter time at 2:00 a.m. the same day only in 33 northern border municipalities, including all of Baja California and designated localities in Chihuahua, Coahuila, Nuevo León and Tamaulipas, according to the Diario Oficial de la Federación.
- The timing rules follow the Uniform Time Act under U.S. Department of Transportation oversight, and proposals such as Illinois’ January 9 request for permanent daylight time require Congressional approval.
- Health experts say the one-hour shift can temporarily disrupt circadian rhythms and advise gradual sleep adjustments, early-morning light exposure, reducing stimulants and confirming whether devices update automatically.