Cornell has a real-time map that shows migration, and is used to predict where the concentrations will be. Click the map to be taken to https://birdcast.info/.
Starting March 1st, the BirdCast Migration Maps forecasting resumes.
BirdCast Live Migration Maps
How to Use
Other resources:
Journey North has various bird and non-bird migration maps.
If you need to brush up on your warbler id skills TheWarblerGuide.com has various guides, visual, audio, free downloads from princeton.edu.