Tonight, migration is weak in the eastern US, except in front of the storm front in the northeast, where there are strong returns that we haven't seen much of yet this spring. There is decent movement up the Great Plains. Take a look at the wind map for the explanation - strong winds from the south carrying migrants up the plains, with strong northwest winds impeding birds behind the storm system in the northeast:
Compare these patterns with several nights ago, when there was strong movement across most of the country. Note generally weak winds in most areas where birds are moving, and strong south winds off the Gulf coast to get them started:
As another influence of weather on migration, I noticed a neat effect here in NY. There are strong migrant returns at the Binghamton, Syracuse, and Albany radar stations where the storms haven't reached yet, but as the rain approaches the birds drop off Binghamton and Albany's radar. Perhaps birding could be good there in the morning?