First Alert Weather In-Depth: Snow squalls

ROCHESTER, N.Y. (WHEC) — Every winter in the Finger Lakes we see lake effect snow, and specifically snow squalls, but what’s behind them?

Currently, the water temperature of Lake Ontario is 42º. That is pretty mild, especially when you have very cold, Arctic air that is crossing the Great Lakes. That warm, moist air wants to rise. Think of it almost like a hot air balloon and then it becomes a function of wind direction. You are going to get condensation and clouds developing. That wind pushes that moisture downwind over land that where we start to get some of those heavy snow squalls. It is almost like a fire hose that takes place.

What is a heavy snow squall and how does it develop? We know it happens very suddenly with intense bursts of snow and wind. That combination just plays havoc with the visibility. As result, we get whiteout scenarios and we can easily get one to three-inch snowfall rates per hour from any one of these big snow squall events.

So we know the amount of snowfall is going to be rather heavy on the west side of town. You can see how the amounts go up the closer you are to Buffalo because this is coming in off Lake Erie.

The big concern is going to be the New York State Thruway. The Thruway goes right through the core of some of that heavier snow. We think this is going to be a big problem as we go through tonight and tomorrow morning.