Alaska.
Guatemala is the Central American country farthest to the west.
The farthest West.
The city of Quincy is furthest west. The town of Hamilton is actually farthest west. It's approx. 3,100 people, so it tends to be forgotten. But that's where I'm from, and it is farther west than Quincy.
Philippine Trench
Barbados
Texas
Austin, Texas
Key West.
Dallas, Texas lies at approximately 32.7767° N latitude and 96.7970° W longitude. This city matches the given criteria.
The country that lies to the west of Texas is Mexico. Mexico is separated from Texas by the Rio Grande River.
Alaska... i know it is far fetched but true.