Since Saratoga Springs is in upstate New York, there are 4 seasons.  You can always find something to do here in any season, but of course winter is quieter as the racetrack is closed .  If you are a skier, you'll love the area though it's a bit south from most ski resort areas.  Most of the stores are always open, though most cut hours after the summer.  You just never know what the weather will be here, being a meteorologist in the upstate region is like being a borderline psychic!   You just never know.  Layering is highly recommended.  Always bring rain gear and a sweater or sweatshirt even if it is July or August.  September and later is beautiful for foliage, apple picking, and other fun outdoors fall events.  It's cooler and there are some wonderfully fun apple picking places, and there is a balloon festival in September just north of Saratoga in Glens Falls/Lake George region.  No matter the time of year there is plenty to see and do, but be prepared for any weather.