It's that time of year again folks. You may be heading out the door early in the morning this week, especially yesterday and this morning, and remember the huge temperature tumble we just had of over 50 degrees in less than 24 hours. We were just in the mid 70s on Sunday afternoon and we dropped all the way into the low 20s for Monday morning and this morning. Needless to say, seeing that your low tire pressure light on your dashboard is possible. Is it a flat tire? Probably not. Leak? Also not the main culprit. A lot of the time, weather is to blame for your low tire pressure light coming on when there is a decrease in temperature, but why?

Tire pressure can decrease about 1 PSI (pounds per square inch) for every 10 degrees the temperature drops. It's not due to air leaking out, but instead it's the air inside the tire condensing, taking up less space when it's cold. This is temporary, because driving will heat up the tire and increase the tire's pressure.

A lot of the reasoning behind why this happens is because of the molecules inside the tire. Cooler air molecules can take up less space inside your tire and exert less force on tire walls. As temperature drops, molecules slow down. When it’s hot, molecules will move faster and increase tire pressure. 

Image Courtesy: NWS

As the cold front rolled through our area on Sunday night, we will end up going from highs in the mid 70s to temperatures on Monday morning in the low to low 20s. So, temperatures dropped about 50 degrees meaning the PSI in your tires dropped around 5 or more PSI. 

Even if you don't think it is a tire leak and just the cold weather, it can still make way for dangerous conditions on the roadways, so checking your tire pressure often is always recommended.