Seasonal Outlook for the Great Lakes - Winter 2011-2012

At the end of November water temperatures were generally near normal (Figure 3). Air temperatures over Lake Ontario are forecast to be slightly above normal in December and near normal for the rest of the winter.

Lake Ontario will remain ice free in the first three weeks of December. New and thin lake ice will form in Bay of Quinte late in the third week of December. The bay will be covered with thin lake ice near the end of the month. Otherwise at the end of December ice free conditions will prevail in Lake Ontario except open water along the northeast shore. Figure 5 indicates the expected ice conditions on January 1, 2012.

Normal air temperatures are expected in January. Patches of new and thin lake ice will form in the western end of the Seaway and in shallower bays of the northeast shore in the first week of January. At that time, the Bay of Quinte will become consolidated with thin lake ice. In the third week of January, the western end of the Seaway will consolidate with medium lake ice and consolidated ice in the Bay of Quinte will thicken to the medium lake ice stage. Also in the third week of January, the coastal ice in the north-eastern section of the lake will gradually expand to about 10 to 20 nautical miles offshore. By the end of the month, most of the north-eastern portion of the lake, from Long Point and eastward, will be covered with thin with some medium lake ice. New and thin lake ice will occasionally form elsewhere around the shores but will melt rapidly as it is pushed offshore by passing storms. Figure 7 indicates the expected ice conditions on February 1, 2012.

The ice in the western end of the Seaway and in the Bay of Quinte will reach the thick lake ice stage near mid-February. At that time thin and medium lake ice will be found in the north-eastern portion of the lake. Narrow bands of new and thin lake ice will be found at times along the shores of the rest of the lake but will be blown offshore and melt rapidly. Conditions on March 1, 2012 are shown in figure 9.

Break-up will occur at a near normal pace.