10. Cross breeze is strong enough to obstruct your vision by unfolding the brim of your stocking cap into your eyes (not fun at 80 mph. Believe me, I know).
9. You didnít order an iced cappuccino at Starbucks.
8. Six sweaters youíre wearing make it difficult to rest your elbow on the door.
7. Toll taker gets impatient waiting for you to remove your ski gloves to fish the coins out of the coinholder.
6. Highway patrol pulls you over to administer a field insanity test.
5. Furry brim on parka hood introduces a whole new set of blind spots.
4. Your thermally challenged better half in the passenger seat starts interviewing divorce attorneys on her cell phone.
3. The snowman on your front lawn shakes its head in incredulity as you pull out of the driveway.
2. What you think is cowl shake or unbalanced tires is actually uncontrolled driver shivering.
And the number one way to tell it might be too cold to drive your Z3 with the top down: