With this severe cold, the air pressure in our car tires has plunged because of the ideal gas law.
https://www.lesschwab.com/article/tires/what-should-tire-pressure-be-in-winter.html
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The Ideal gas LAW is not a theory!
https://courses.lumenlearning.com/suny-physics/chapter/13-3-the-ideal-gas-law/
Figure 3. (a) When air is pumped into a deflated tire, its volume first increases without much increase in pressure. (b) When the tire is filled to a certain point, the tire walls resist further expansion and the pressure increases with more air. (c) Once the tire is inflated, its pressure increases with temperature.
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We see in the example that the change in tire pressure with temperature is about 1 psi for every 10 °F change in temperature for a 40 psi tire pressure at 68 °F. In Figure 2, I look at two different air temperatures. You will notice that for a given tire pressure, the pressure change with temperature increases with lower reference temperature.
Figure 3 shows a graph of how the tire pressure (40 psi @ 68 °C) varies with temperature.
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I got a warning about my tire pressure being low yesterday when the temperature was 10 deg. F.
The tire pressure had dropped to 29 psi in all the tires, so I pumped them up to 32 psi.
When the temperature gets back above 50 degrees F, the tire pressure is going to get back above 35 psi.