1.   An impenetrable fog halted traffic.

2.   An impenetrable fog overcast our view of the harbor.

3.   Athough other vehicles are scarce, you may find yourself trailing a truck and traveling for miles in an impenetrable crimson fog that it creates.

4.   During an impenetrable fog Friday at Perris, I missed setting the hook on my only two obvious strikes.

5.   He rescued himself from sun blindness, impenetrable fog and empty gas tanks.

6.   In fact, there was little motion in the capital on Monday, which was covered with snow and wrapped in an impenetrable fog from dawn to dark.

7.   On the last curve before the straightaway to the line, he whipped ahead into the impenetrable fog and was gone.

8.   Then they hit impenetrable fog.