Things are really heating up now as we push into the latter half of April. Southerly flow across most of the country triggered heavy migration from Mexico to New Jersey. Locally, the southerly flow allowed for a moderate to heavy flight of birds into the Garden State and as far north as central New York. Here’s the radar from sunset last night through 5:00am this morning.

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

 

Once the sun set last night, the radars really began to crank with nocturnal migration. Here’s the national composite for midnight last night (peak migration density): http://www.rap.ucar.edu/weather/radar/nids/images/N0R/KUSA/20110419_035900.png.

Here are a couple of interesting things you can pick out of that image: First, migration along the Gulf and Southeast is really heavy! Neotropical and Caribbean migrants have been arriving for weeks now and are making their way north into the rest of the US. In that image you can also really see how the frontal boundary to the north marks the limit of northbound migration. Especially in the northeast, where heavy migration abuts the frontal boundary, we should expect some higher concentrations of birds on the ground. The Binghamton area, for instance, looks particularly good this morning.

Looking at Dover and Fort Dix we see fairly typical spring migration on southerly winds. Birds are heading SSW->NNE across New Jersey which will favor inland locations such as the Delaware Bay Shore (and Belleplain) in Southern NJ, and Garret Mountain further north. Areas to the west will also have more birds this morning as the source pool of migrants is naturally higher to the west, while areas on the east side of the main trajectory will have comparatively less birds. Cape May, for instance, should glean the least number of birds from this flight given it’s position in the ‘migration shadow’ (it is considerably off-axis from the major spring trajectory across NJ). That said, the ‘island effect’ down here does have a way of pulling in good stuff- so while quantity may not be in the cards, quality is always an option.

Further north we did see some migration into southern New York, Manhattan and Long Island last night. Winds over eastern NY were more southwesterly and thus we had more movement out to the east. As I mentioned before, along the frontal boundary last night there should be some fallout conditions. Therefore if any of you New Yorkers had heavy rain around midnight be sure to check your local patch this morning.

For tonight and tomorrow night it’s wash-rinse-repeat, so get ready for a mid-week birding bonanza!

Good Birding

David