Distribution of Foggy Weather around the U.S.

  • Where is it foggy????
    • Pacific Coast
    • Appalachian highland region
    • New England
  • Foggiest spot in the U.S.: Cape Disappointment, WA
    • it's foggy for 2556 hours per year, or about 107 days.
  • Other foggy locations:
    • Mistake Island - off coast of Maine - 1580 hours per year
    • Mt. Washington!! - experience fog on about 300 days each year!

Fog can be a significant forecast problem:

  • aviation
  • ground transportation
  • maritime activities


1.  Explain why icebergs are frequently surrounded by fog.

2.  During a summer visit to New Orleans, you stay in an air-conditioned motel. One afternoon, you put on your sunglasses, step outside, and within no time your glasses are "fogged up." Explain what has apparently caused this.

3.  A January snowfall covers central Arkansas with 5 inches of snow. The following day, a south wind brings heavy fog to this region. Explain what has apparently happened.