Tomorrow I am going to refill my two 5lbs CO2 cylinders.
I'll be running errands for a few hours afterwards. Is there any risk with keeping the tanks in the car for a long time? Tomorrow won't be as hot as today and yesterday but still could be on the 80s.
First of all, I have no idea Armando, but good luck with that.
Secondly, I saw pictures in a firefighting magazine years ago (when I fought fires a little and read firefighting magazines a lot) of the side of an engine where a SCBA bottle stored in a compartment had ruptured, and blown a 5 foot crater out of the truck. Made me think twice next time I strapped one to my back (picture of Wile E. Coyote flashes through mind).
I imagine CO2 bottles aren't presurized that high, but still, good to be careful.
You are unlikely to have any problems. If there is any chance the tanks are leaking a bit I'd be careful about airing your car out when you first get in.
Just got home in the past hour Heat wasn't really a problem but the rain was crazy! I was afraid of someone hitting my car and having the thing explode (bad drivers + rain = terrible drivers ). i changed a bit my itinerary so the CO2 refill went close to the end of my "journey".