Mega bird migration

Watch the bird migration at night.

The weather radar that detects rain can also detect birds. When there is no precipitation the operators set the radar in a very sensitive mode that detects birds. I don't know how to directly access the radar. But Cliff Mass of U of W captured the bird activity on Saturday, September 7. The birds mostly fly at night to avoid predators. He has a series of radar captures from the new Langley Hill radar near Ocean Shores, Washington, showing little activity before sunset, heavy activity at night, then a sharp drop at sunrise.

Cliff Mass describes this at his CM Weather Blog.

Here are a radar image before sunset and one only an hour later, after sunset. It's amazing the leap in activity. Images from Cliff Mass.