Texas & Austin: The Only Gulf Coast State on the 100th Meridian

A Geographic Trifecta

Texas is the only U.S. state that simultaneously:

1. Has a coastline on the Gulf of Mexico
2. Is crossed by the 100th meridian west (100°W)
3. Has its capital (Austin) on that meridian

Significance of the 100th Meridian

This longitude historically marks the climatic boundary between the humid East and arid West—roughly where annual precipitation drops below 20 inches. It runs through:

• Texas Panhandle (north)
• Near Lubbock
• Through Austin (~97.7°W actually—see note)
• South Texas brush country

Important Correction

Austin is actually at ~97.7°W. The 100th meridian passes west of Austin (through Uvalde, Del Rio area). However, Texas is still the only Gulf Coast state intersected by the 100th meridian. The premise contains a slight inaccuracy regarding Austin's exact longitude.