You should follow the reccomendations in your owner's manual.
Also available is the tire build decal or "placard", usually located in the driver's door jamb aka "B Pillar", which gives the suggested pressures based on tire size (if applicable) and load.
This pressure is checked/adjusted cold, which means undriven tires in the morning, in the shade. This will work no matter where you do it, and what the morning is like. I would check twice if I was driving from Yuma to Juno, or versa-vice, but I don't think that's what you're asking.
There's no real problem inflating to the maximum sidewall pressure stipulated on the tire (cold), with the caveats it may affect ride comfort, handling, and tire wear. Add a few extra pounds if you really think you need it, but never exceed sidewall maximum cold.