Evening flight into the Haze

Friday, July 18th was hot with temperatures in the mid 90's. I decided to take a flight in the evening to avoid the heat as best I could. I got to the airport around 1845hrs but the temps were still around 88 as I did my preflight. I planned on a 1930 departure and a flight over to Ridgely and back to see the sunset. One of my frequent fliers met me and we launched from Runway 10 and headed toward the bay. There was a awful lot of haze despite the fact that the visibility was supposed to be 10 miles. When we got over to Ridgely there was another aircraft in the pattern practicing a GPS instrument approach on the opposing runway. Because it was starting to get dark I decided against a landing and turned back toward the bay. The sun was in the process of setting behind a wall of haze. As we got back over toward Tipton it was getting to be dusk and the light from cars and Annapolis city were starting to light up. We came in to runway 28 and be the time were taxied from the fuel dock it was already dark.