The typical retreat of the sea ice cover from the late winter to late summer is shown on this map. Sea ice is any form of ice that is found at sea and has originated from the freezing of seawater. Melting of sea ice begins in spring in the Gulf of St. Lawrence and East Newfoundland, retreating northward towards the Labrador coast. In June openings appear in Baffin Bay and the Beaufort Sea, while clearing is already underway in Hudson Bay. Break-up continues throughout the summer months, reaching a minimum extent around mid-September. The map shows the typical retreat of the sea ice cover from late winter (mid-March) to late summer (mid-September) on a bi-weekly basis. The dates shown in the legend of the map indicate the extent of the sea ice cover at those dates.