the pacific time zone is one of the time zones in the world. it is based on the mean solar time of the 105th meridian west of the greenwich observatory. normally, its time is 8 hours before coordinated universal time. the time zone is in the united states, canada and mexico. the biggest city in the zone is los angeles, california; its metropolitan area is the largest in the zone. during daylight savings time, the pacific time zone is represented by utc−7.