A lot of drivers are pulling into tire repair shops with flat tires or tires that have suddenly had the air pressure drop. It’s due to the extreme cold, and it’s dangerous. Inside Tires Plus in St. Anthony Village, it has the feel of an emergency room: Cars and trucks hoisted up on lifts and tires under inspection. If your tire pressure is too low, you have less control of your vehicle. “It’s very important to check your air pressure once a month. A lot of data says twice a month. Because of the temperature fluctuations, you need to maintain that proper air pressure,” Matt Johnson, the Tires Plus manager, said.