It pays to have an inexpensive tire pressure guage in the glove compartment and check all four tires once a month and before taking a long trip. Besides causing excess wear and fuel consumption the wrong pressure adversely affects braking.
In snow you can lower the pressure slightly, but be sure to pump it up as soon as you clear the snow area. In Russian military trucks there are valves on the floor to alter the indivual tire pressure, depending on conditions. Low pressure for snow and mud. Normal pressure for highway driving.