World Series of Birding Migration update

Composite NEXRAD for midnight

This should have gone up last night in preparation for the big day but better late than never!

Composite NEXRAD for midnight

The World Series of Birding is a big fundraising event in New Jersey run by New Jersey Audubon. Teams race across the state (or a specific county), tallying up as many species as they can from midnight to midnight. Weather can play a huge role in how the day turns out; many species are just arriving and a good night of migration is the difference between hoping to luck into a single individual versus enjoying a cacophony of so many bird songs that you have to tear yourself away from each stop along your route just so you can stay on schedule.

The approaching low system set up excellent migration conditions and birds took advantage, as evidenced on the radar. You can see the strong south -> north flow in the velocity radar below on the right. Migration was very heavy as the storm moved through the state between midnight and 1am. This can be on the early side to set up a good fallout, but the sheer volume of birds hints at World Series teams stumbling across great concentrations of migrants.

Hopefully the weather is drier today so that the teams can get out and find all the migrants that arrived last night! Good luck to all the teams competing this year.


The strong migration also boosted the chances that teams will be able to find some of the later arrivals such as flycatchers which can be very scarce if migration is backed up.


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-

Upper Midwest – Woodcreeper by David La Puma
Michigan’s Upper Peninsula – The Northwoods BIRDAR by Max Henschell
New England – Tom Auer’s blog
Florida/SE – Badbirdz Reloaded by Angel and Mariel Abreu
NW Ohio – Birding the Crane Creek by Kenn Kaufman
Pac NW – Birds Over Portland by Greg Haworth
Continental US – eBird BirdCast Forecast & Report by Team eBird
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!