The Grand Banks of Newfoundland justly deserves its reputation as one of the stormiest places on earth. The tracks of the storms leaving the North American continent frequently pass over or near the Grand Banks, particularly in the winter and early spring. In some cases the storms explosively intensify as they leave the east coast, and by the time they reach the Grand Banks they carry storm or hurricane force winds. These storms are sometimes called “weather bombs”, which is defined as a low pressure system that experiences a decrease in central pressure of 24 millibars in 24 hours. Winds can exceed 100 km/h (62 mph) and seas 15 m (about 50 ft).
Photo of the IIP Ice Reconnaissance Detachment HC-144A in bad weather.
The sharp contrast in the sea surface temperatures between the Gulf Stream and the cold waters of the Labrador Current and on the Grand Banks brings persistent fog to the area. Foggy conditions can exist most of the year, but they are especially prevalent in the late spring and early summer as air temperatures rise and sea temperatures near the Grand Banks remain cold. Most people associate foggy conditions with calm winds. This is not necessarily true near the Grand Banks, where the fog can be so widespread that it can persist even in windy conditions.
The combination of frequent storms, persistent fog, and the presence of sea ice and icebergs creates extraordinarily hazardous conditions for mariners.