This report describes the typical weather at the Erik Nielsen Whitehorse International Airport (Whitehorse, Yukon Territory, Canada) weather station over the course of an average year. It is based on the historical records from 1977 to 2012. Earlier records are either unavailable or unreliable.
Whitehorse, Yukon Territory has a humid subarctic continental climate with cool summers and no dry season. The area within 25 mi of this station is covered by forests (77%), tundra (19%), and lakes and rivers (2%).
Over the course of a year, the temperature typically varies from -6°F to 68°F and is rarely below -34°F or above 78°F.
The warm season lasts from May 17 to September 9 with an average daily high temperature above 56°F. The hottest day of the year is July 26, with an average high of 68°F and low of 47°F.
The cold season lasts from November 17 to February 21 with an average daily high temperature below 20°F. The coldest day of the year is January 6, with an average low of -6°F and high of 8°F.
The length of the day varies significantly over the course of the year. The shortest day is December 21 with 5:38 hours of daylight; the longest day is June 20 with 19:08 hours of daylight.
The earliest sunrise is at 4:27am on June 14 and the latest sunset is at 11:37pm on June 26. The latest sunrise is at 10:12am on December 25 and the earliest sunset is at 3:45pm on December 16.
Daylight savings time (DST) is observed in this location during 2012, starting in the spring on March 11 and ending in the fall on November 4.
The median cloud cover ranges from 79% (partly cloudy) to 92% (mostly cloudy). The sky is cloudiest on November 12 and clearest on March 25. The clearer part of the year begins around February 7. The cloudier part of the year begins around May 29.
On March 25, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 42% of the time, and overcast or mostly cloudy 54% of the time.
On November 12, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy 79% of the time, and clear or mostly clear 20% of the time.
The probability that precipitation will be observed at this location varies throughout the year. Precipitation is most likely around November 16, occurring in 69% of days. Precipitation is least likely around April 18, occurring in 37% of days.
Over the entire year, the most common forms of precipitation are light snow, light rain, and moderate snow.
Light snow is the most severe precipitation observed during 49% of those days with precipitation. It is most likely around November 25, when it is observed during 54% of all days.
Light rain is the most severe precipitation observed during 28% of those days with precipitation. It is most likely around August 22, when it is observed during 37% of all days.
Moderate snow is the most severe precipitation observed during 10% of those days with precipitation. It is most likely around November 11, when it is observed during 13% of all days.
During the warm season, which lasts from May 17 to September 9, there is a 52% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of light rain (62% of days with precipitation have at worst light rain), moderate rain (21%), thunderstorms (10%), and light snow (5%).
During the cold season, which lasts from November 17 to February 21, there is a 61% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of light snow (80% of days with precipitation have at worst light snow) and moderate snow (18%).
The likelihood of snow falling is highest around November 25, occurring in 67% of days. The season in which it is relatively likely for snow to fall spans from September 26 to April 29.
During peak snow season, accumulation at this location on a given day is just more likely than not. The chances of there being snow on the ground are highest around December 14, occurring 63% of the time. The season in which snow is relatively likely to be on the ground spans from October 18 to April 22.
The snow is typically at its deepest on March 17, with a median depth of 11.4"; the depth exceeds 16.7" only one year out of ten.
The relative humidity typically ranges from 32% (comfortable) to 89% (very humid) over the course of the year, rarely dropping below 21% (dry) and reaching as high as 100% (very humid).
The air is driest around May 15, at which time the relative humidity drops below 38% (comfortable) three days out of four; it is most humid around October 26, exceeding 84% (humid) three days out of four.
Dew point is often a better measure of how comfortable a person will find the weather than relative humidity because it more directly relates to whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid.
Over the course of a year, the dew point typically varies from -13°F (dry) to 48°F (dry) and is rarely below -43°F (dry) or above 53°F (very comfortable).
Over the course of the year typical wind speeds vary from 0 mph to 17 mph (calm to moderate breeze), rarely exceeding 26 mph (strong breeze).
The highest average wind speed of 9 mph (gentle breeze) occurs around October 15, at which time the average daily maximum wind speed is 17 mph (moderate breeze).
The lowest average wind speed of 7 mph (light breeze) occurs around July 9, at which time the average daily maximum wind speed is 14 mph (moderate breeze).