"Key West radar has had a busy night, but not because of weather!" tweeted the National Weather Service Key West.
CNN  — 

A weather radar in Key West, Florida, exploded in a wave of hundreds of red, orange, and green dots early Monday morning.

It would have been quite a storm, if the activity wasn’t almost completely due to migrating birds.

The birds showed up on the radar in green and yellow. Rain was visible on the radar in darker blue colors, according to the Twitter post.

The National Weather Service wrote in a separate tweet that this activity is typical during this time of year, as birds migrate back to their homes after flying South for winter.

Curious Twitter users wanted to know what types of birds were showing up on the radar, but the National Weather Service could only narrow it down to 118 possibilities.

A graphic created by Cornell University researchers shows the migratory patterns of 118 types of birds across North and South America.

Last September, the National Weather Service Key West posted a gif to Twitter showing multiple flocks of birds migrating south over the island.