The radar last night leaves much to be desired…and way too much to interpretation. So here are the conditions: Surface winds had a southwesterly component, while winds aloft were primarily from the west. I’m thinking that this explains why you see a mix of S–>N and N–>S flows in the velocity image. Of course, with the hot day and cool night there was definitely a temperature inversion after sunset causing some anomalous propagation. Movement across the radar is slow going (around 10 – 15kts) but without a tail wind (and actually since they are fighting a west wind, although not very strong) it’s possible that most of the N–>S movement is indeed bird migration. Either way, migration last night did seem greatly reduced from the past two nights, so whether it’ll be noticeable on the ground is still up for grabs (actually, it’s up for YOU to grab, and bring it back here…and report it…got it? seriously!).

Good Birding 🙂