Please take a few seconds to fill out a very short survey to help me improve woodcreeper.com. It will take less than a minute, and can be found here, or by clicking the ONLINE SURVEY button on the right-hand sidebar. Thanks in advance! -David

Some interesting happenings on the radar last night… but in order to make any sense of them we’re going to have to read between the pixels…
here’s the radar from 6:00pm last night through 5:00am this morning.

Frames are every 1/2 hour. Click on the thumbnail to view the full-sized animation.

Last night’s WSW winds precluded most birds from migrating, although both the velocity and reflectivity indicate some movement over the state. The best explanation for this is the difference between the surface and high elevation winds whereby birds flew at higher altitude to avoid the adverse surface winds (which were coming out of the SW). The velocity image shows this well, with two apparent trajectories present at the peak of migration (around 10:00pm). In the center of the image you can see passage across the radar from SW->NE, indicating objects moving with the wind (dust, pollen, insects, etc.), but outside of this and extending to the perimeter of the radar’s view (which represents higher elevation since the radar picks up objects that are higher up as one moves away from the center of the radar beam… think “ice cream cone” with the outer rim of the radar beam equal to the rim of the cone) we see movement from N->S, which is consistent with birds flying at around 2000-3000 feet last night, where the winds were light from the northwest. Granted this was not a large push of birds, but the lack of a significant tailwind means that they will probably not go very far, which might cause bird densities to build up at places like Cape May (where many birds probably stayed put, given the adverse surface conditions). It’ll be interesting to get some field reports this afternoon and see if this is indeed evident on the ground.

Good Birding

David

P.S. Come check out my migration forecast for the Mid-Atlantic on Birdcapemay.org

Please don’t forget to become a member of the Woodcreeper/Badbirdz flock today. For more information, please check out the Become a Member post.