I'd have thought the temperature of the air in the tyre affects pressure, regardless of whether this came from the ambient air temperature, or has been raised by tyre flex in use.
It may only change by 2 psi, which isnt important as tyre pressure gauges can be this inaccurate anyway. More important is pressures are equal between left and right, so avoiding measuring one side in the sun and the other in the shade is sensible.
But lets assume that in an average summer temperature a 'cold' tyre is 36 psi, but the extra heat generated when driven raises this to 38 psi. Its likely that the ideal psi for driving is actually 38 psi. If you were to check the pressure on a hot tyre and its 38psi you might let out air until its 36 psi, But when the tyre is again cold it would only be 34 psi.
In the colder winter ambient air temperature 36 PSI may drop to 34 psi for a 'cold' tyre. The extra 2 psi from being driven only raises it 36psi , which is still 2 psi below what is ideal. So topping 34 up to 36 restores the status quo. Extreme heat and extreme cold may affect things but probably not by enough to worry about. Hypothetical figures.
