Since the rain has now abated, and winds are easterly and thus no longer oppose northward movement, it is likely that lots of migrants will depart shortly after sundown. If so, they are likely to be visible on radar (rap.ucar.edu is a good site for viewing such departures), or audible as flight notes in the sky overhead immediately after dark. Sometimes a pulse of flight calls overhead seems to happen in spring around 9 pm as well, which I presume is the overhead passage of the concentration of migrants originating on the immediate Gulf Coast.
Migration is so cool!
Peter
Update next day:
The exodus was not as large as I anticipated- perhaps the migrants could detect the rain bands north of the lake at sunset, and chose not to take flight. However, some departure still appears evident on the images below- see how the dark blue blob (apparent departing birds) starts south of the Lake at 9 pm and is gone (actually gradually shifting northward across the lake to merge with/replace the echoes there) three hours later.
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