The Climate of Canada

Newfoundland has a Humid Continental climate (Köppen climate classification Dfb) influenced by coastal currents and icebergs. Summers are usually pleasant but brief. July mean temperatures remain cool along the southern and eastern coast, especially, with mean daily temperatures in the low to mid teens Centigrade. However, the interior enjoys warmer mean temperatures slightly above 15°C. In July, the maximum temperature can even occasionally rise to as high as 30°C in the interior! In winter, the Gulf of St. Lawrence, and the North Atlantic Ocean waters prevent temperatures in Newfoundland from dropping too far. Mean January temperatures range from -9°C to -7°C in the interior, to around -4°C, on the southern coastal areas.

Coastal fog is very frequent in the spring, on the east coast, because of the icebergs off shore. In the summer, when warm air flows from the south quadrant over the cold waters surrounding Newfoundland, fog engulfs the southwestern and southern coast… occasionally for days!

The entire island receives an abundant amount of precipitation, usually peaking in November, and reaching a minimum in April. Winter snowfall is normally in excess of 250cm everywhere, with amounts exceeding 400cm in parts of the western interior.

Spring rains often fall on still frozen ground and objects. Thus, ice storms are frequent in southern Newfoundland.

Airports

The following map shows the Köppen climate classification (KCC) for aerodromes across Canada which are listed on SKYbrary:

Climatic and Weather Phenomena Affecting Aviation in Canada

• Fog - Fog, often persistent, affects airports in Newfoundland in spring and summer.
• Snowfall - although airports in the region are comparatively well prepared for winter weather, heavy snowfall can serious affect operations and runway availability (see articles on Landing on Contaminated Runways and Runway Surface Friction). Pilots should also take care to ensure clearance from snow banks while taxying.
• Ice Storms - Freezing Rain is a significant hazard between February and May.
• Low Temperatures - Although the Atlantic waters moderate the temperatures during the winter months, care should be taken to apply Altimeter Temperature Error Correction when the aerodrome temperature is 0°C or colder.