<P> Some United States Minor Outlying Islands are outside the time zones defined by 15 U.S.C. § 260 and exist in waters defined by Nautical time . In practice, military crews may simply use Zulu time (UTC ± 00: 00) when on these islands . Baker Island and Howland Island are in UTC − 12, while Wake Island is in UTC + 12: 00 . Because they exist on opposite sides of the International Date Line, it can, for example, be noon Thursday on Baker and Howland islands while simultaneously being noon Friday on Wake Island . Other outlying islands include Jarvis Island, Midway Atoll, Palmyra Atoll, and Kingman Reef (UTC − 11: 00); Johnston Atoll (UTC − 10: 00); and Navassa Island, Bajo Nuevo Bank, and Serranilla Bank (UTC − 05: 00). </P> <P> In Antarctica, the US research facility Palmer Station is in UTC − 03: 00, while McMurdo Station and Amundsen--Scott South Pole Station use UTC + 12: 00 in order to coordinate with their main supply base in New Zealand . </P> <P> (Described from north to south along each boundary .) </P> <Ul> <Li> roughly follows the border between Wisconsin (to the south and west) and the Upper Peninsula of Michigan (to the north and east); the Upper Peninsula counties that border Wisconsin (namely Gogebic, Iron, Dickinson, and Menominee counties) observe CT, all other counties in the U.P. observe ET </Li> <Li> follows Lake Michigan </Li> <Li> divides a small portion of Northwestern Indiana near Chicago from the rest of the state </Li> <Li> follows the border between Illinois (west) and Indiana (east) </Li> <Li> divides a small portion of Southwestern Indiana from the rest of the state </Li> <Li> divides Kentucky in half roughly along a line that is west of Louisville, Kentucky running from northwest to southeast . </Li> <Li> divides the region legally defined as East Tennessee, except for four counties adjoining Middle Tennessee, from the rest of Tennessee . </Li> <Li> follows the border between Alabama (west) and Georgia (east), although Phenix City, Alabama and some nearby towns unofficially observe Eastern Time . </Li> <Li> divides the Florida Panhandle along the Apalachicola River and Intracoastal Waterway just west of Tallahassee, Florida . </Li> </Ul>

What are the four time zones of the united states