Meteorologists discovered the blue blob on Duluth's weather radar was a sea of birds flying south.
Bring Me The News reports the seagulls and lake gulls popped up on the radar, showing weather along the North Shore of Lake Superior on Tuesday morning.
"The bird density was about 3-6 birds at a time onscreen," said the National Weather Service in Duluth. "Radar returns are based on the diameter of the scatterer to the 6th power. So the birds look like large hail stones, they really light up the display even though there aren't as many as you'd think."
Okay, so it wasn't really a sea of gulls, but at least the weather service's explanation satisfies my inner nerd.
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