[CapriRacer]

Allow me to start in a different place:

What to ignore:

Elevation: Even at 5,000 feet (Denver), the amount of inflation pressure change from sea level is only 2 1/2 psi - not enough to worry about.

Humidity: Just not a factor

So we are only talking about temperature vs pressure.

In summer, we can expect at 20°F change from early morning to the hottest point of the day. That would be a 4% change - 80 psi to 83 psi - again, not enough to worry about.

The problem in winter is 2 fold:

1) Water vapor can freeze about of humid air at as little as 37°F. That means that one should avoid check inflation pressures when it gets below - say - 40°F. That also means that, in winter, one should anticipate colder temperatures and set the tire inflation pressures to cover the worst temperatures in the coming months. When I lived in Michigan, the worst temperature I anticipated was -20°F, but I would set the pressures for 0°F, reasoning that if it got to -20°F, I was not going to travel fast (which causes additional stresses) nor for very long.

Which brings me to:

2) Setting the pressure in a warn environment, with the expectation of operating in a cold environment.

So lets say the pressures are set at 50°F, and the expect operating temperature is 0°F, then the expect loss of pressure would be 10%. So an 80 psi tire should be set at 88 psi.

Doesn't that exceed the max pressure on the sidewall? Yes, but not only are tires designed for a much higher pressure (long story why that is!), but the tire isn't expected to operate at that pressure - the tire will cool down to a lower pressure.

You can use that chart to help set pressure for anticipated conditions - except that the chart doesn't show what I just outlined above. Ergo, I would recommend NOT using this chart.