We should all know better when there's snow and ice on roads and highways.
But that doesn't mean we do.
And that's why people get stuck, and need help getting out.
Even for those who aren't afraid of heights, clawing your way across a frozen overpass can still be a white-knuckle — and sore-bottom — affair.
"Car shaking... you just get nervous," said one motorist who was among those who were stuck on a highway flyover in West Fort Worth Tuesday morning.
They were lucky to get some personal attention getting un-stuck from a police officer and a Texas Department of Transportation worker shoveling grit under the tires for better traction.
"Don't hit your brakes... just let it all the way down," said the TxDOT worker as he guided one car out of its slippery predicament.
The cars got stuck after slipping semi stopped at the top of the frozen ramp — and everyone else had to stop, too.
After the semi moved on, the smaller vehicles were iced in place.
"I stopped because all the idiots in front of me stopped... that's pretty much it," one driver griped. "It only takes one moron to screw up the whole day for everybody."
TxDOT crews were placed on alert overnight, ready to take action if damp bridges and overpasses get icy again before the Wednesday morning rush hour.