8:00 pm – 8:30 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 bat pups have been flying for about 6 weeks now, so flights can be great nowadays, especially if a front moves through that stirs up insect activity.

Sunset: 7:51 pm
Dark: 8:21 pm (10-20 min). earlier if cloudy)
Sunrise: 7:09 am