Here’s a refresher course what the AP Stylebook says for datelines and cities that stand alone in datelines.
The domestic list of cities that stand alone is on page 79 of the 2010 AP Stylebook, and it is a good idea to mark this page with a sticky note of some sort so it is easy to find and you never list the state, country or territory unnecessarily. You can also find a list of international cities that stand alone, but I’ve only listed the domestic list below for easy reference.
You can bookmark this post so that the domestic cities list is always a click away, which saves time thumbing through those pages for those who don’t have sticky notes. Here's the list of international dateline cities.
Remember that, in datelines, the city name is in all capital letters. If necessary, follow it with the state abbreviation –– not the U.S. postal code. For example: KANSAS CITY, Kan. or KANSAS CITY, Mo. (However, these states are always spelled out: Alaska, Hawaii, Idaho, Iowa, Maine, Ohio, Texas and Utah.)
Domestic cities that stand alone:
ATLANTA BALTIMORE BOSTON
CHICAGO CINCINNATI CLEVELAND
DALLAS DENVER DETROIT
HONOLULU HOUSTON INDIANAPOLIS LAS VEGAS LOS ANGELES
MIAMI MILWAUKEE MINNEAPOLIS NEW ORLEANS NEW YORK
OKLAHOMA CITY PHILADELPHIA PHOENIX PITTSBURGH
ST. LOUIS SALT LAKE CITY SAN ANTONIO SAN DIEGO SAN FRANCISCO SEATTLE
*On a regional level, additional cities may stand alone should the newspaper staff decide so.