Slow night of migration across the region

Regional Overview

The volume of migrants in the air was greatly reduced last night compared to the last several nights. The primary cause of this was the moderate south wind that dominated the region last night. The velocity radar bears out the the idea of little migration last night as the radar did not detect objects (birds) heading in a southbound direction against the wind.


Wednesday night into Thursday morning look like the next chance for a big pulse of southbound migrants. Thrushes are still moving through en masse so if you have a quiet spot to listen, Wednesday night could be a good time to give that a try. Sparrows will be starting to make a big push into the Northeast/Mid-Atlantic/Ohio Valley over the next couple weeks. White-throated Sparrows have already started to show up in numbers at more northern sites but the next few weeks should see large movements of other species as well such as Chipping and Savannah Sparrows.

I don’t always have time to comment on the radar in each state. To interpret it yourself, read the quick tutorial at the bottom of the page.

New York

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Pennsylvania & New Jersey

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Maryland and Delaware

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Quick guide to interpreting the radar

On the top row (reflectivity radar), the images show the magnitude of migration. When birds are migrating, it looks like a donut shape around the center of the radar station.

The bottom row is the velocity radar. This shows the direction that the objects detected by the radar station are moving. Blues are moving towards the radar station, yellows and reds are moving away from the station. So for southbound migration, blue should be on the top half of the donut, yellow on the bottom half.

Watch for precipitation moving through during the night hours, this can cause birds to stop migrating in a concentrated area, creating the fabled ‘fallout’, particularly on nights with strong migration.

For more in depth info, watch this video.
For migration updates or other regions check-

Pac NW – Birds Over Portland by Greg Haworth

National Forecast – Birdcast (also posts NYC and Philly specific forecasts)

I need your help! These reports will only be as good as the feedback I get on these updates. Please leave comments on interesting patterns of migration you are seeing in the field so I can incorporate some ground truthing to my forecasts and predictions. Thanks!