Migration and NEXRAD
NEXRAD radar maps like this show a combination of radar images from across a region. This image is from March 28, but you can type in any date to look at what happened at other times. On this map you can see:

• a large line of rain and storms associated with a front moving across the country;
• ahead of that front (to the right) are southerly winds;
• that's where you see a bunch of blue circles;
• these circles are birds taking off on migration!
• notice that behind the front (to the left), you don’t see those circles. That’s because the winds are from the north, so birds are staying where they are, waiting for the winds to become favorable again. Pretty cool!

Paul Hurtado and NEXRAD
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