Sudden temperature drop

I used to be one of those people who disapproved of Xmas decorations dragging on into the Spring, but today the temperature dropped SO fast and hard that you cling to small signs of cheer in The Bleak Midwinter.  Brr.  And the term started and I teach at 8:00 in Flushing on Mondays and Wednesdays, and it was still dark when I arrived.  Well, at least we're not driving to White Lake any more.  But I was NOT happy to see my "low tire (/tyre) pressure" symbol lit up, especially as I was just as Discount Tire and they claimed to have fixed the slow leak.  Why does it always do that when you will die of exposure as you're trying to pump up your tires?