Massive Bat Colony Shows Up On Weather Radar

A colony of bats in Arizona created a cloud so big it showed up on weather radar.

The National Weather Service tweeted photos of what appeared to be a giant cloud over Phoenix and Mesa.  But it wasn't rain - it was Mexican free-tailed bats, leaving their summer home and migrating south.

Bat-watching is actually a popular activity in Arizona, which is home to more than 28 species of the flying mammals.