Daylight Saving Time

It's that time of year when we change our clocks. Why? Daylight Saving Time. While there are a lot of interesting factoids about Daylight Saving Time and its history, these are the ones you should know.

  • Colorado is in Daylight Saving Time (DST) from the second Sunday in March until the first Sunday in November, eight months out of the year.

  • During DST, Colorado's time zone is called Mountain Daylight Time. The other 4 months, Colorado is in Mountain Standard Time (MST).

  • Arizona (except for the Navajo Nation) doesn't observe DST, so Colorado is only in the same time zone as Arizona between November and March. They always stay in Mountain Standard Time. (Hawaii also does not observe DST.)

  • DST used to start the last Sunday in April and end the last Sunday in October, until 2007 when the Energy Policy Act of 2005, opens a new window extended it.

  • DST was adopted to conserve fuel during WWI by reducing the need for artificial light, then repealed after the war ended. It returned during WWII and was again repealed after the war.

  • Because DST could be started and ended by states and localities whenever they pleased, there was A LOT of confusion. Thus, the Uniform Time Act, opens a new window was established which gave us the start and end dates of DST.