Daylight Saving Time - What is it?

When Do I Change My Clock?

Beginning in 2007, most of the United States begins Daylight Saving Time at 2:00 a.m. on the second Sunday in March and reverts to standard time on the first Sunday in November. In the U.S., each time zone switches at a different time.

Spring forward, Fall back

During DST in the spring, clocks are turned forward an hour, effectively moving an hour of daylight from the morning to the evening. In the fall, the hour is given back by moving the clocks an hour back.

Date change in 2007

On August 8, 2005, President George W. Bush signed the Energy Policy Act of 2005. This Act changed the time change dates for Daylight Saving Time in the U.S. Beginning in 2007, DST will begin on the second Sunday in March and end the first Sunday in November. The Secretary of Energy will report the impact of this change to Congress. Congress retains the right to resume the 2005 Daylight Saving Time schedule once the Department of Energy study is complete.

When do I change my clocks in the morning?

In the U.S., clocks change at 2:00 a.m. local time. In spring, clocks spring forward from 1:59 a.m. to 3:00 a.m.; in fall, clocks fall back from 1:59 a.m. to 1:00 a.m. In the EU, clocks change at 1:00 a.m. Universal Time. In spring, clocks spring forward from 12:59 a.m. to 2:00 a.m.; in fall, clocks fall back from 1:59 a.m. to 1:00 a.m.

In the U.S., restaurants and bars have various closing policies. In many states, liquor cannot be served after 2:00 a.m. But at 2:00 a.m. in the fall, the time switches back one hour. So, can they serve alcohol for that additional hour in October? The official answer is that the bars do not stop serving liquor at 2:00 a.m., but actually at 1:59 a.m. So, they have already stopped serving when the time changes from Daylight Saving Time into Standard Time. In practice, however, many establishments stay open an extra hour in the fall.

In the U.S., 2:00 a.m. was originally chosen as the changeover time because it was practical and minimized disruption. Most people were at home and this was the time when the fewest trains were running. It is late enough to minimally affect bars and restaurants, and it prevents the day from switching to yesterday, which would be confusing. It is early enough that the entire continental U.S. switches by daybreak, and the changeover occurs before most early shift workers and early churchgoers are affected.

Some U.S. areas For the U.S. and its territories, Daylight Saving Time is NOT observed in Hawaii, American Samoa, Guam, Puerto Rico, the Virgin Islands, the Commonwealth of Northern Mariana Islands, and Arizona. The Navajo Nation participates in the Daylight Saving Time policy, even in Arizona, due to its large size and location in three states.

Source:The information from this blog post came directly from http://webexhibits.org/daylightsaving/b.html.