Chilkoot Trail National Historic Site of Canada

Weather

Storm brewing over Chilkoot Pass.
© Parks Canada

Mountain weather is highly unpredictable. It can change quickly and/or vary greatly from one location to another. Regardless of the season, hikers can expect wet, cold, windy and/or whiteout conditions; severe rain or snow storms are possible even in the middle of summer. Avalanche hazard persists until mid-July . If hiking in the early season you should be properly equipped with shovels, avalanche transceivers and probes, so as to be able to find and rescue a member(s) of your party if they get caught in an avalanche.

Most weather systems blow in from the coast. As moist ocean air rises to go over Chilkoot Pass, it cools and loses its ability to hold moisture, producing precipitation. As a result the US side of the trail tends to be rainy and/or overcast. The section of the trail between Sheep Camp and Deep Lake is above tree line and frequently experiences severe weather conditions - driving rain, sleet, hail or snow, low temperatures, high winds and fog - as weather systems move through the area. As cool air descends from the alpine tundra to the shores of Lindeman Lake, it becomes warmer and its ability to hold moisture increases, creating a "rain shadow". Weather in the low lying areas at the north end of the trail tends to be drier, a pleasant contrast to conditions which prevail on the rest of the trail.

Winter weather conditions can be extreme and unpredictable. Conditions above treeline can be especially severe. High winds and driving snow may prevent travel through this open country. Temperatures vary from -46 C/-50 F to -1C/+30 F. It snows up to 508 cm/200 inches per year. Be prepared for snow, rain, sleet and winds in excess of 80kph/50mph. Visibility of less than 8 metres/25 feet is common. Whiteout conditions can prevent detection of hazardous avalanche terrain, open water and overflow, and complicate route finding. Weather can also play a major role in the development of avalanche hazard.