Daylight Saving Time (DST) is the practice of advancing clocks during warmer months so that darkness falls later each day. This means enjoying longer evening daylight hours during the spring, summer, and fall. But when exactly does this clock-shifting event occur, and what time does daylight saving time actually start?
In the United States, Daylight Saving Time begins on the second Sunday in March. At this time, at precisely 2:00 a.m. local standard time, clocks are moved forward one hour, becoming 3:00 a.m. local daylight time. This “spring forward” effectively steals an hour of sleep but gifts us with extended daylight into the evening.
Understanding the 2:00 AM Shift for Daylight Saving Time
The specific time of 2:00 a.m. was chosen for the changeover for practical reasons. It’s a time when minimal disruption occurs to most people’s schedules and transportation systems. By making the change in the early morning hours, it minimizes confusion and allows for a smoother transition into daylight saving time.
This change is mandated across most of the United States by law, specifically outlined in the U.S. Code regarding Standard Time. Congress has adjusted the start and end dates of Daylight Saving Time over the years, with the current schedule established by the Energy Policy Act of 2005. This act set the current pattern of starting DST on the second Sunday in March and concluding it on the first Sunday in November.
A Brief History of Daylight Saving Time in the U.S.
While the concept of standard time zones was adopted in the U.S. in 1883, Daylight Saving Time has a more fluctuating history. It was initially introduced in 1918 alongside standard time but was quickly repealed in 1919. Daylight Saving Time was revived nationally during World War II and remained in place until after the war, after which its observance became inconsistent across different regions.
To standardize the practice, the Uniform Time Act of 1966 was enacted. This law initially set Daylight Saving Time to begin on the last Sunday in April and end on the last Sunday in October. However, these dates have been adjusted over time, sometimes in response to energy concerns, like during the energy crisis in the 1970s when DST started earlier in the year.
The most recent significant change came with the Energy Policy Act of 2005, which moved the start of Daylight Saving Time to the second Sunday in March and the end to the first Sunday in November, beginning in 2007. This is the schedule the United States currently follows.
Exceptions to Daylight Saving Time
It’s important to note that not all of the United States observes Daylight Saving Time. Hawaii and most of Arizona remain on standard time year-round. These locations do not spring forward or fall back, maintaining consistent time throughout the year.
Furthermore, while many countries around the world observe some form of summer time, the specific dates and rules vary significantly. Most of Europe and North America participate in Daylight Saving Time, while some countries in the Southern Hemisphere also observe it, but with reversed timings due to their summer occurring during the Northern Hemisphere’s winter. There is no international agreement dictating Daylight Saving Time schedules.
In conclusion, if you’re in a location that observes Daylight Saving Time in the United States, remember to set your clocks forward by one hour at 2:00 a.m. local standard time on the second Sunday of March. This marks the beginning of Daylight Saving Time and the start of longer evenings until the fall.
