Sep 22, 2022, 12:00 midnight
| Start DST: | Tuesday, March 22, 1977 — 1 hour forward |
|---|---|
| End DST: | Thursday, October 20, 1977 — 0:30 hours backward |
Mar 21
Forward 1 hour
Mar 21, 1977 - Daylight Saving Time Started
When local standard time was about to reach
Monday, March 21, 1977, 11:00:00 pm clocks were turned forward 1 hour to
Tuesday, March 22, 1977, 12:00:00 midnight local daylight time instead.
Sunrise and sunset were about 1 hour later on Mar 22, 1977 than the day before. There was more light in the evening and less light in the morning.
Also called Spring Forward, Summer Time, and Daylight Savings Time.
Oct 21
Back 0:30 hours
Oct 21, 1977 - Daylight Saving Time Ended
When local daylight time was about to reach
Friday, October 21, 1977, 12:00:00 midnight clocks were turned backward 0:30 hours to
Thursday, October 20, 1977, 11:30:00 pm local standard time instead.
Also called Fall Back and Winter Time.
Daylight Saving Time in Other Years
DST changes do not necessarily occur on the same date every year.
| Year | DST Start (Clock Forward) | DST End (Clock Backward) |
|---|---|---|
| 1970 — 1976 | DST not observed | |
| 1977 | Monday, March 21, 11:00 pm | Friday, October 21, 12:00 midnight |
| 1978 | Saturday, March 25, 12:00 midnight | Saturday, August 5, 1:00 am |
| 1979 | Saturday, May 26, 12:00 midnight | Wednesday, September 19, 12:00 midnight |
| All times are local for 29°51'29.2"N, 60°50'40.0"E. | ||
Data for the years before 1970 is not available for 29°51'29.2"N, 60°50'40.0"E, however, we have earlier time zone history for Tehran available.
Detailed time zone and clock changes in 29°51'29.2"N, 60°50'40.0"E