Should a tire's pressure be changed for outside temperature?

Joe's Question: "Should I under-inflate my tires by a little so that they have room to expand up to their "max" when it's hot outside?"

Great question. Since air is a gas, it expands when heated and contracts when cooled. Most people know that this means that your tire pressure will change with the outside air temperature, but it also means that it will change from morning garage temp to daily commute temp since just the routine flexing of the tires sidewalls during driving will cause temperature increases. So, is it a good idea to under-inflate to compensate?

My recommendation would be this:
Since the manufacturers recommended tire pressure is a "cold" tire pressure, make sure you are checking it cold. First thing in the morning before driving is best. Also make sure you are using the car manufacturer's recommended inflation located in the owners manual or door jamb and not the "max" inflation listed on the sidewall of the tire, since this can be rated for a car that weighs as much as a thousand pounds more or less than yours. Then finally, I would suggest that in Arizona, you start with about 2-3 psi below the automakers recommendation when checked cold in the morning. Also make sure you check the tire pressure at least once a month and adjust as needed.