This report describes the typical weather at the Trondheim Airport (Stjørdal, Norway) weather station over the course of an average year. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Stjørdal 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 (62%), oceans and seas (16%), croplands (10%), tundra (5%), and lakes and rivers (3%).
Over the course of a year, the temperature typically varies from 22°F to 66°F and is rarely below 4°F or above 76°F.
The warm season lasts from June 2 to September 6 with an average daily high temperature above 59°F. The hottest day of the year is August 3, with an average high of 66°F and low of 52°F.
The cold season lasts from November 15 to March 14 with an average daily high temperature below 39°F. The coldest day of the year is December 30, with an average low of 22°F and high of 33°F.
The length of the day varies significantly over the course of the year. The shortest day is December 21 with 4:30 hours of daylight; the longest day is June 20 with 20:38 hours of daylight.
The earliest sunrise is at 2:58am on June 16 and the latest sunset is at 11:38pm on June 25. The latest sunrise is at 10:02am on December 26 and the earliest sunset is at 2:27pm on December 16.
Daylight savings time (DST) is observed in this location during 2012, starting in the spring on March 25 and ending in the fall on October 28.
The median cloud cover is 88% (mostly cloudy) and does not vary substantially over the course of the year.
On April 19, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 40% of the time, and overcast or mostly cloudy 51% of the time.
On September 13, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy 77% of the time, and clear or mostly clear 16% of the time.
The probability that precipitation will be observed at this location varies throughout the year. Precipitation is most likely around September 19, occurring in 74% of days. Precipitation is least likely around April 19, occurring in 62% of days.
Over the entire year, the most common forms of precipitation are moderate rain, moderate snow, and light rain.
Moderate rain is the most severe precipitation observed during 50% of those days with precipitation. It is most likely around September 11, when it is observed during 56% of all days.
Moderate snow is the most severe precipitation observed during 22% of those days with precipitation. It is most likely around January 15, when it is observed during 38% of all days.
Light rain is the most severe precipitation observed during 14% of those days with precipitation. It is most likely around June 12, when it is observed during 14% of all days.
During the warm season, which lasts from June 2 to September 6, there is a 70% 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 moderate rain (72% of days with precipitation have at worst moderate rain), light rain (18%), and thunderstorms (6%).
During the cold season, which lasts from November 15 to March 14, there is a 69% 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 moderate snow (48% of days with precipitation have at worst moderate snow), moderate rain (24%), light snow (18%), and light rain (7%).
The likelihood of snow falling is highest around January 13, occurring in 52% of days. The season in which it is relatively likely for snow to fall spans from October 24 to April 28.
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 February 26, occurring 56% of the time. The season in which snow is relatively likely to be on the ground spans from November 14 to April 6.
The snow is typically at its deepest on February 5, with a median depth of 5.8"; the depth exceeds 13.3" only one year out of ten.
The relative humidity typically ranges from 47% (comfortable) to 94% (very humid) over the course of the year, rarely dropping below 28% (dry) and reaching as high as 100% (very humid).
The air is driest around May 14, at which time the relative humidity drops below 58% (mildly humid) three days out of four; it is most humid around August 21, exceeding 91% (very 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 16°F (dry) to 55°F (comfortable) and is rarely below -0°F (dry) or above 61°F (comfortable).
The time of the year between June 19 and September 5 is the most comfortable, with dew points that are neither too dry nor too muggy.
Over the course of the year typical wind speeds vary from 1 mph to 16 mph (light air to moderate breeze), rarely exceeding 31 mph (high wind).
The highest average wind speed of 9 mph (gentle breeze) occurs around January 5, at which time the average daily maximum wind speed is 15 mph (moderate breeze).
The lowest average wind speed of 7 mph (light breeze) occurs around August 12, at which time the average daily maximum wind speed is 13 mph (moderate breeze).