Question about efficacy of Quinclorac and other weed killers in regards to storage temperature

I don’t have a temperature controlled garage, and so left my weed killers outside under the porch since last summer. Two weeks ago I sprayed Quinclorac from last year that has been through 100° days and -5° days. It hasn’t done jack shit to any of the weeds. Is it trash now? If so, is storing it in a garage that’s basically a uncooled/unheated huge shed built in the late 1920s any better than leaving it in the shade on the porch? I’d prefer not to store weed killers in my house if I can keep from it.