AT&T California in Eureka, CA
These numbers are located in the city of Eureka part of Humboldt county. There are a few other subcodes that cover this area as well so take care not to confuse them.
Humboldt county is situated in California and operates PT (UTC -08:00) time. This number group covers the 95501, 95502, 95503, & 95534 zip codes.