Here’s the radar from sunset last night until sunrise this morning. Now, although the reflectivity looks impressive, if you check the velocity you’ll notice something fishy. It appears that there are two directions that things are moving through the radar beam (direction is from – to +, or in this case, from green/blue – yellow/red). Winds were from the West/Southwest last night, which means there were probably less birds migrating last night than the initial visual appearance of the radar image would suggest. The winds were fairly light, so some of the movement seen in the velocity from NE to SW, was probably some stronger flying bird species, but the majority of the signal was likely a combination of anomalous propagation and some particulate in the air (dust, pollen, etc.).