For most Americans there's an hour's less sleep tonight in exchange for longer days during the next few months.

At 2 a.m. local time Sunday, daylight saving time, that harbinger of spring, arrives with the promise of longer, light-filled days well into the evening.

Turn that clock ahead - remember, spring forward - before heading to bed Saturday night to avoid the panic of rising later than you think.

Not every place makes the switch, though. Hawaii, Arizona outside the Navajo Indian territories, Puerto Rico, the Virgin Islands, American Samoa, Guam and the Northern Marianas stay on standard time, which returns for the rest of us Nov. 4, two days before election time.