Tire Pressure vs. OAT vs. a happy median

[Paul T]

I love my TST TPMS but now that I know every morning what the individual PSI readings are, (without getting down on my knees or back to manually manipulate a pressure gauge), I’m curious what you other folks do when transiting different temperature zones.
Left central Florida last week with all tires set at 110 PSI. It was 95 degrees when the pressure was set and my TPMS verified close to those reading departing the next day with a temperature in the high 80s. That’s a bit higher than what I was running previously but I knew I’d get a bit of a drop heading into cooler air up north. Now, at 4,400 ft. in North Carolina and 60 degrees outside last night, all tires are reading near 100 PSI. That’s a bit lower than I desire but within limits for my axel weights.

“Tire Rack” says “The rule of thumb is for every 10° Fahrenheit change in air temperature, your tire's inflation pressure will change by about 1 psi (up with higher temperatures and down with lower).” But is that rule of thumb true at the higher pressures we run our RV tires? I seem to get a much greater fluctuation closer to 2 or 3 PSI per 10 degree change in temperature.

So for you engineers out there, at what OAT should one set the desired pressure? Does Michelin use a standard temperature like they do in the aviation industry on their charts and if so what is it? Has anyone seen an adjustment to the chart pressures for temperature deviation?