Posted by: woodcreeper | September 20, 2007 @ 6:05 am

Wheel in the sky keeps on turnin’


Round and round it goes…where it stops, nobody knows. Well, that was pretty much the story last night, for the spinning low pressure cell over Florida. Here’s the radar from sunset last night through sunrise this morning.

Frames are every 1/2 hour for reflectivity and velocity, and every hour for the regional composite. Click on the thumbnail to view the full-sized animation.

Base Reflectivity image from Key West, FL Base Velocity image from Key West, FL
Base Reflectivity image from Miami, FL Base Velocity image from Miami, FL Composite base reflectivity for the Southeastern USA

I think the regional composite tells the best story. Just after sunset birds are seen taking off from the southeastern US (GA, AL, SC, etc.) and the panhandle of Florida. Winds in northeastern Florida were out of the east, and birds definitely took off in high numbers just after sunset but were quickly shut down by the passing storm cells and associated winds. Birds are also seen taking off from the central Florida radars, although this only lasts for a few hours until winds switch around there as well. In south Florida we saw birds take off immediately after sunset with strong westerly winds sending them right over the coast and into the Atlantic. That push was short-lived, though, as there was no influx of birds making it into southeast Florida since the points north were already shut down when the winds turned from west to south during the night. Now here’s the real question:
Given that migration over the Jacksonville area was shut down early, did localized fallout conditions occur?
In southeastern Florida, even though most of the push appeared to go out into the Atlantic, was there enough of a coastal push to cause a detectable increase in birds along the coast? I await some reports from the field!

Good Birding! 🙂


  1. A bried stop at the east side of Matheson Hammock this morning produced the following:

    Black-throated Blue Warbler 1
    Prairie Warbler 2
    Ovenbird 3
    American Redstart 4
    Parula 1
    Red-eyed Vireo 10
    Blue-gray Gnatcatcher 10

    We had some heavy storms late last night, but it’s difficult to say whether they caused any amount of fallout. The species composition and numbers of individuals above is consistent with what’s been seen in that location for several days, so these may just be lingering birds and not new arrivals. A stop yesterday on the service road failed to produce the Canada Warbler seen the day before (9/18), nor any of the N. Waterthrushes and Ovenbirds that littered the road the previous afternoon. Tuesday night brought north winds, so many of the birds may have continued south. So far the best birding this fall has been between Sunday and Tuesday, with Kentucky, Chestnut-sided, Tennessee, Swainson’s, and Canada being some of the better birds seen. Trey Mitchell had an 18 warbler species day on Monday. I saw 14 species at A.D. Barnes on Tuesday morning, then added Canada at Matheson in the afternoon for a 15 species day. With two TAS walks scheduled for Saturday and Sunday, we will be able to compare species composition and numbers for this week.



%d bloggers like this: