Incredible lake-effect snow has verified across the eastern shores of the lakes Erie and Ontario this weekend, some areas across the Tug Hill Plateau received even more than 50 inches (4 feet or 120 cm) of snow in around 48 hours period. Below are details with satellite imagery as well as numerous reports from the infected cities.

Note: Lake-effect snow develops when a very cold air mass (usually during the Polar / Arctic outbreaks) moves across the warmer lake (or sea, e.g. Black Sea, Adriatic sea, or Baltic Sea in Europe) water. The layers of air closer to the lake surface are heated up by the warm lake water, picking up moisture/water vapor from the lake and rises up through the colder air advection above. This results in convective squalls and bands of heavy snow. Snow is then deposited on the leeward (downwind) side of the lakes (seas) shores.

Convective cloud streets (lake-effect snow bands) were perfectly seen from the satellite during the peak time of the event, Friday, Feb 28th. The most defined areas are marked on the map, eastbound of the lakes Michigan, Erie and Ontario:

A day after, we could see a lot of deep snow coverage over the same areas, Feb 29th:

Snow totals have reached more than 50 inches (4 ft / 125 cm) eastbound of lake Ontario, across the area southeast of Watertown – precisely the Tug Hill Plateau.




Reports of huge amounts of snow accumulated from the Tug Hill Plateau – town Copenhagen wast of the city Watertown.




Satellite animations of the maintaining convective cloud streets producing heavy snowfall on the east-southeast sides of the lakes. A wider view of the water vapor satellite indicates a long dry slot wrapping around the low in Quebec which was powering the event. See also a spectacular visualization of the lake-effect snow trajectory:






Here are various reports during the heavy snowfall (LES) event:







High winds across the lakes also produce high waves, causing the water spray to develop thick ice layers on the shores.





See the forecast discussion of how this event unfolded:

Extremely dangerous lake-effect snowfall with up to 4 feet (120 cm) of snow is expected across the Tug Hill Plateau, New York state (USA) until Saturday


An impressive satellite view of the large cyclone over the Northeast US – intense lake-effect snowfall event is developing across the Great Lakes tonight through Sunday