"From New Mexico, the same front curved generally westward to central Arizona and eastern California. This front marked the boundary where colder air was fairly stagnant in the Rocky Mountain region, denoted as a front"

Maritime tropical MT.

Explanation:

The maritime tropical is warm for that form the new Mexico region flows to the higher and upper altitudes of the California and is generally curved to westwards to the Arizona and the eastern boundary of the California and marks a boundary between the rocky mountain regions.

Answer the collision of tectonic plates;