FLAGSTAFF, Ariz. — As temperatures drop and fall arrives in Arizona, some may be wondering when the trees in the northern part of the state will turn from green to yellow, orange and red.

Flagstaff welcomes millions of tourists a year. To make it easier for them to view the autumn leaves, city officials are LEAFometer.

LEAFometer is a webpage that allows you to see where the trees are starting to change color before traveling to areas like Flagstaff or Sedona. LEAFometer starts with a green color, which indicates the leaves haven't started to change color yet, and turns bright red when the leaves are at their most beautiful.

This page also features the best places to observe the color changes, from the San Francisco Peaks to Oak Creek Canyon.

Looking for something fun to do during your stay? Click here for Fall Events This season, the event will be held in the Flagstaff area.

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