November 25, 2014

Lake-Effect Snow vs. Sound-Effect Snow?

Buffalo, New York is digging out from its most recent snowstorm, which dumped up to seven feet of snow in parts of the city. Buffalo is prone to high volume snowstorms, often the victim of lake-effect weather.

The National Oceanic and Atmospheric Administration describes how lake-effect snow occurs:
  1. cold air masses move over warmer lake waters;
  2. the warm lake water heats the bottom air layer, causing lake  moisture to evaporate into the cold air;
  3. the evaporated moisture rises, cools, condenses, and forms clouds;
  4. snow falls!
Lake-effect snow is most common and heaviest in the Great Lakes region, but it can occur downwind from other large water bodies if the water is free of ice. This includes Long Island Sound, albeit not often.

According to the National Weather Service, reported in a CTNews blog, although the air around the Sound can be cold enough, the area of open water is not long enough for the air to blow over and pick up the moisture needed to produce significant ‘Sound-Effect’ snow. (The longest area over Long Island Sound is 75 miles, whereas over Lake Erie it is 220 miles and over Lake Ontario it is 170 miles.)