You are missing the Mountain time Zone of the United States. There are 4 zones in the continental U.S. Eastern, Central, Mountain and Pacific. You are missing the Mountain Time Zone, which is one hour earlier than the Central Zone. Some states within the Mountain Time Zone (like Arizona) do not use Daylight Savings Time, but you already have a switch to turn it off or on. States in the Mountain Time Zone Include Arizona, Colorado, Utah, New Mexico, and Alberta Canada.
The Mountain Time Zone of North America keeps time by subtracting seven hours from Coordinated Universal Time (UTC) when standard time (UTCâ07:00) is in effect, and by subtracting six hours during daylight saving time (UTCâ06:00). The clock time in this zone is based on the mean solar time at the 105th meridian west of the Greenwich Observatory