low tire pressure warning

[GPSnV1]

I was ready to drive home and suddenly I'm confronted with the dreaded low tire pressure warning. I get the detailed window about what to do with RFTs (which I have) and gingerly make my way home to change clothes and check out the tires.

All the tires have the same reading and are well below standard. I call dealer and say did the significant drop in temps have anything to do with this? Yes. We've done 30 today. Come in and we'll get it right.

Is this going to happen every time there is a big drop in temps? Service said that a 30 degree drop (90 to 60) is enough to trigger this kind of behavior.