Even on a dreary day, 'It's Always Sunny' in Center City

We didn't see much sun Thursday, but if you were around Logan Square or on Chestnut Street near 17th, you might have spotted the cast of "It's Always Sunny in Philadelphia."

The cable sitcom, which moves this fall from FX to help launch its spin-off channel FXX, is in town for a couple of days shooting on location for its upcoming ninth season. By midafternoon, two of its stars, Kaitlin Olson and Glenn Howerton, were filming a scene at 9th and Green streets.

"I'm going to say this is actually a perfect day to shoot," said "Sunny" creator and star Rob McElhenney, who grew up here and knows from Philly weather. "We had one hour of rain and aside from that, it's just been overcast, and overcast is the best weather" for filming.

Plus, "we found - I never noticed it before - that the city has a fair amount of overhang, so there's a ton of architecture ... atriums and open-air spaces with overhang. So even if we had to go to a cover set instead of just shooting out in the street, we're still shooting in Philadelphia, it's still beautiful and we're protected from the rain. So it really wasn't an issue."

Accountant Greg Milos and his wife, Dr. Brooke Davey-Milos, a pediatric cardiologist, got closer to the action than most. They were invited to become extras after McElhenney saw a project Milos had posted online - a Google map pinpointing the places "Sunny's" filmed in Philly.

"It sounds crazy, and I think it is a little bit," Milos said. "It took a couple of years to make."