How the map was drawn

The zones

Zone lines run on 82.5°, 97.5° and 112.5° west, halfway between the meridians where each zone's noon falls. Where a line cuts a metro area, the whole metro goes to whichever side holds more of its people. We used the federal definitions of metro areas, which group counties, and placed population at actual cities and towns inside each county so that empty ranchland on a metro's edge doesn't count like downtown.

Most metros aren't close calls. Detroit is 99 percent west of its line. Phoenix is 86 percent east of its line. A few were close:

Brownsville is the one place we broke our own rule. By population it belongs on the UTC−6 side, but there it would be cut off from the rest of its zone by forty miles of lagoon and barrier island. We gave it to UTC−7 with McAllen.

The lower 48 ends up with four zones, same as now. A sliver of coast in eastern Maine is technically on the next zone east, but it holds maybe fifteen thousand people, so it stays with UTC−5.

Alaska and Hawaii

The sun would split Alaska three ways: the panhandle on UTC−9, Anchorage and Fairbanks on UTC−10, and the west and the Aleutians on UTC−11. That would mean states of about 70,000 and 60,000 people, so Alaska stays one state on UTC−10, where most Alaskans live. Juneau ends up about an hour ahead of the sun and Nome about an hour behind. Nome is two to three hours off today, so this is still better.

Hawaii is one state on UTC−10, the same clock it keeps now. The 157.5° line runs down the channel between Molokaʻi and Oʻahu, and Honolulu sits almost on top of it.

The states

Inside each zone, states are drawn as rectangles of latitude and longitude, so most borders run straight north-south or east-west, the way most of the West was surveyed. Where one of those lines would cut through a metro area, the metro goes whole to the side with more of its people, and the border follows county lines around it.

Wherever we could, we put new borders on old lines that already run along a parallel or meridian: 49° north, 42° north (New York and Pennsylvania, Oregon and California), 40° north (Kansas and Nebraska), the Mason-Dixon line, 36.5° north (Missouri and Arkansas), 43.5° north (Minnesota and Iowa), and 103° west (New Mexico and Texas).

That gives 16 states on UTC−5, 17 on UTC−6, 6 on UTC−7, 9 on UTC−8, plus Alaska and Hawaii. DC stays DC.

We didn't try to give states equal populations. They run from about 740,000 (Alaxsxaq) to about 20 million (Manaháhtaan, which is the New York metro area and can't be split). Today's range is about 580,000 to 39 million.

Calls you might argue with

We split Tampa from Orlando, gave the Cherokee heartland around Knoxville its own state, and gave the San Joaquin Valley its own state, mostly because each of those fixed something about the names as well as the map. Other candidates were splitting Dallas off from east Texas, or Chicago from the rest of northern Illinois.

The populations are approximate, from 2024 county estimates, and the borders are only as precise as the county shapes behind them.

Data

• County boundaries: US Census Bureau cartographic boundary files, via the us-atlas project.
• County populations: 2024 Census Bureau estimates.
• Metro areas: Office of Management and Budget metropolitan statistical area definitions.
• City locations: GeoNames.