The front which brought us plenty of rain yesterday finally cleared during the night, allowing high pressure to build it behind it and triggering a small, late, flight of birds into the region. Here’s the radar from sunset last night through 6:00am this morning.

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

Looking at the regional composite you can really see what I’m talking about. Early in the night the frontal boundary is still draped across the east coast, packing a considerable amount of precipitation. As the front moves eastward during the night, migration-indicative reflectivity appears from the Great Lakes down into the western mid-Atlantic and eventually even along the east coast. The velocity images show most movement heading south, suggesting bird migration. Looking at the individual radar loops you can see that while migration was apparent, it was also pretty light. Migration over Central PA (as seen from the Pittsburgh (KPBZ) and State College (KCCX); not shown here) was considerably greater than along the east coast owing to the better migration conditions earlier in the night. In contrast, the NYC radar showed no apparent migration last night. Fort Dix, NJ and Dover, DE show light southbound migration after the frontal passage.

Light and variable winds tonight could allow more local movements of birds into the region for tomorrow morning, although we’ll need to wait until the next cold front clears to bring a large, regional flight down to the mid-Atlantic. That may happen as soon as Sunday night, but more likely Monday night into Tuesday morning. In the meantime, enjoy the early fall birds!

Good Birding

David