Iran will officially turn the clocks back by one hour at midnight (1930 GMT) on Monday, September 21, to observe Daylight Saving Time (DST).
The shorter hours of daylight in the evenings will run until March 20, 2016, when Iranians will turn the clocks ahead by an hour.
In 2007, Iran’s Parliament (Majlis) passed a bill mandating that the official time be changed twice a year.
According to the bill, the country’s official time will be changed once at the beginning of the Iranian calendar year (beginning March 21 or March 20 in leap years) and once at the start of the second half of the Iranian year.
DST is the convention of advancing clocks by one hour so that evenings include more hours of daylight.
Typically, clocks are adjusted forward one hour in late winter or early spring and are moved one hour back in fall.