Ingredients
Required for Lake-Effect Snowstorm
–Instability: Lake must be very much warmer than air at
mountain crest level (by 17oC or more). Likely when cold northerly/northwesterly
winds blow across the lake.
–Lift: A mechanism to lift air parcels must be present
(e.g., land-breezes from opposing
sides of the lake converging in the center of the lake)
–Moisture: There must be sufficient moisture in the air
approaching the lake for clouds
to form when the air is lifted. Evaporation from the lake is insufficient to generate appreciable snowfall
Despite its small size, the GSL produces
snowbands similar to those observed over the Great Lakes