Weather radar picks up widespread bird migration

The National Weather Service's radar detected an unlikely pattern in Texas on Tuesday: widespread bird migration.

The service tweeted a real-time animation of the ongoing migration, capturing spring birds in the Fort Worth, Texas, area as they flew north for the warmer months.

"What's that on radar?! Winds are generally out of the northwest (blowing towards the southeast) across the area, so what's that moving northward on the radar scopes," NWS tweeted Tuesday morning. "These light returns aren't rain or clouds, but birds continuing their northward migration!"

The post racked up about 300 likes and re-tweets as well as a few comments from curious birdwatchers.

"Looks like an interesting case of super refraction to me," one Twitter user commented.

"So, what about the same echoes at the bottom of the screen, going the opposite direction? Are they already headed south for the winter," another user said, which actually drew a reply from the service.

"It's tough to see in this short loop, but that area is also birds flying north," the NWS replied. "Our radar is just picking up more birds to the south as they fly within range of the radar."

Check out the animation here: