Oh oh! I'm going to get in trouble because I don't normally disagree with Brett. However.
For each 10 degrees of temperature change there will be a 2% increase/decrease in pressure. I beleive the misunderstanding is when one takes 2% of 35 psi it comes out to 0.7 psi and rounded up would be 1 psi. However if you take 2% of 110 psi, it comes out to 2.2 psi.
For every 1000 feet of elevation change there will be a 0.48 psi increase/decrease in temperature.
If you look at the inflation tables and take those measurements into consideration you would set your pressure between the low and high pressure that would give you the most comfortable ride and have the "fudge" factor. I'm not going to go look up the tables, but let us say for example that your weight is 9500 pounds on the heaviest tire and the pressure to abosorb that minimum weigh is 85 psi. You could set your tire pressure to 90 or 95 psi and have a fudge factor of 5 to 10 psi. Consider that at 2% of 90 psi is 1.8 psi so if the temperature dropped 10 degrees you would be at 90-1.8 or 88.2 still within the minimum pressure for the load. If the temperature were to drop 20 degrees you would still be at 85.6 and withing load limits. Normally if you are decreasing in altitude you would be increasing in temperature so there is also a fudge in those factors.
Editied: I did a search in the Goodyear tire chart guide and this is what it states:
"The effects of temperature and atmospheric pressure.
Air temperature and atmospheric pressure effect tire inflation pressure. If the outside temperature increases 10 degrees F, tire inflation pressure increases approximately 2%. Conversely, when the outside temperature drops 10 F, the tire inflation pressure lowers approximately 2%.
Tire inflation pressure increases approximately .48 psi for every 1,000 feet of altitude due to changes in atmospheric pressure. On the other hand, tire inflation pressure will decrease approximately .48 psi for every 1,000-foot decrease in altitude.
In other words, if there are changes in temperature or altitude during your trip, it’s important to check your tire
inflation more frequently."
Or use the fudge factor and you don't have to keep adjusting the tire pressures.
p.s., you did not say the make of your tires. What are they?
Here is a good link to anything you want to know about tires: Tireman's Blog Roger Marble is an engineer that has worked with tire companies for many years.