The basic thermo-dyamic equation is PV=RT (Pressure x volume = an atmospheric constant x pressure Since "R" is essentially the same every where on earth, it boils down to PV=T. In this equation, T is on the absolute scale.
Comparing temperature and pressure, the equation becomes P1*V1/T1 and is constant, disregarding leakage. If your tires are at a certain summer (or hot tire) temperature when you park it, the pressure will drop as winter sets in.
Just re-inflate to the recommended pressure before you start your spring travels, then keep tabs on it as the season warms up. Loss of pressure in storage isn't a harbinger of doom down the road.
