When outdoor temperatures change by relatively extreme amounts, your tires suffer.  As air temperatures change, so does the pressure in your tire.  When air heats up, it expands, causing your tire pressure to slightly rise, and when the air cools down, your tire pressure drops.

I looked in to this phenomenon when both my and my wife's 'check tire pressure' lights came on in our cars.  Personally, I don't check my tire pressure as often as I should and with a winter like we've been having, it's definitely caused a problem.  So when my light popped on today and I stopped to fill up my tires, I was shocked when all of my tires were anywhere between 5-10 psi lower than recommended.

As a general rule of thumb, your tire pressure will rise and drop by about 1 psi per 10 degrees Fahrenheit of change in the air temperature.  This change in tire pressure will increase when the air temperature changes more rapidly than normal.  Also, keep in mind that simply by driving your car, the air will heat up in your tires and cause your pressure to rise.  So when you check your pressure, try to do it before you are on the road for a long amount of time.

And with the way the temperatures have been fluctuating in West Michigan these last few weeks, your tire pressure is probably more than few psi off of it's recommended pressure.  So, if you haven't checked your pressure in the last month, I'd suggest you do so before we see even more poor driving conditions due to weather!