Your Weather Questions Answered How do you forecast lake effect snow? Print Story Published: 4/07/2008 2:24 pm Share Updated: 4/07/2008 2:25 pm When arctic air moves into Western New York, 13WHAM meteorologists will be looking for certain criteria for lake snows to develop. First, the surface temperature must be cold enough for the snow not to melt. Secondly, temperatures at approximately 5000 ft in altitude must be about 15 degrees Celsius colder than the lake water temperature. The lake water warms the cold air at the surface and it begins to rise. This creates what we call lake induced instability. We also need winds to be blowing at the nearly same direction through this layer. If they are not, the intensity of the snowfall can be drastically reduced. If all these are present, we most likely include lake snow in our forecasts. The real forecast difficulty lies in determining exactly where and to some extent and how much snow will fall. Print Story Share Categories Your Weather Questions Answered Snow Wind & Wind Chill Thunderstorms Optical Effects Weather Forecasting WHAM Weather Book Read It Online Download PDFs: Color | B&W