There are
1,561 mi
from Harlingen, TX to Temecula, CA
That's the driving distance. It would take 1 day 3 hours to go from Harlingen, Texas to Temecula, California.
The flight distance (direct flight from Harlingen, TX to Temecula, CA) is 1,267.57 mi.
1,561 mi = 2,511.39 kms