8:20 pm – 8:50 pm

 when conditions allow, i.e. when the atmosphere is stable, no pressure drops, no strong wind or rain in the area, If conditions look good (low or no wind), get there early!
The Congress bats have weaned their pups, so flights will start getting great soon, especially if a front moves through that stirs up insect activity.

Sunset: 8:22 pm
Dark: 8:52 pm (10-20 min). earlier if cloudy)
Sunrise: 6:51 am