Where and When is S Observed?

Sierra Time Zone is often used in aviation and the military as another name for UTC -6. Sierra Time Zone is also commonly used at sea between longitudes 97.5° West and 82.5° West.

The letter S may be used as a suffix to denote a time being in the Sierra Time Zone, such as 08:00S or 0800S. This is spoken as "zero eight hundred Sierra".

Only showing up to 16 cities, others may also be observing Sierra Time Zone.

This time zone is in use, but not observed in any location at this time.

Other Time Zones in UTC -6

Some time zones exist that have the same offset as S, but can be found under a different name:

• CST – Central Standard Time
• EAST – Easter Island Standard Time
• GALT – Galapagos Time
• MDT – Mountain Daylight Time