Welcome, Sidd!
I'm in northern Ohio, and it seems excessively early for you to be thinking your outdoor growing season is nearing it's end. We have cool days - up to 98 last week, down to 70 yesterday - but we still have the entire months of August and September to come! While you may be at a higher elevation, it doesn't seem likely that your temps are such that the peppers will start struggling any day soon. In general, peppers don't like their "feet" (roots) to get below 50F. Because of where I live now (formerly TX and CA), I grow all my peppers in pots so that I can haul them inside as weather demands. I don't expect to even think about doing that before September - though surprises do happen!
I overwinter at least some of my plants - whatever will fit - and put as many as possible in south-facing windows. As long as the majority of the day has sun coming in, this is sufficient for them to bud, bloom, and produce pods. It may still be a bit too early for you to get sufficient sun in that window yet, however. If you do find a need to bring them indoors before late September (ideally even October), as long as it's only for a day or two you shouldn't need to supplement the light. However, if it's longer-term, you may want to use artificial lighting for a while until you get more hours of sunlight directly in that window.
Something to consider before bringing them indoors permanently for the winter: repotting them with fresh soil. Aphids and some other bugs like to hide out (go dormant) or lay their eggs in the dirt once it starts getting cool, then upon warming up after bringing them indoors, you might find a nasty little problem occurring. Repotting won't totally eliminate the chances of this happening, but will reduce them.