Climate and Average Weather Year Round in Tromsø NorwayIn Tromsø, the summers are short, cool, and mostly cloudy and the winters are long, freezing, snowy, windy, and overcast. Over the course of the year, the temperature typically varies from 21°F to 59°F and is rarely below 9°F or above 70°F. Based on the tourism score, the best time of year to visit Tromsø for warm-weather activities is from mid July to mid August. Average Temperature in TromsøThe warm season lasts for 2.7 months, from June 13 to September 4, with an average daily high temperature above 53°F. The hottest month of the year in Tromsø is July, with an average high of 59°F and low of 48°F. The cold season lasts for 4.6 months, from November 12 to March 30, with an average daily high temperature below 35°F. The coldest month of the year in Tromsø is January, with an average low of 21°F and high of 29°F.
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day. Average Hourly Temperature in Tromsø
frigid
15°F
freezing
32°F
very cold
45°F
cold
55°F
cool
65°F
comfortable
75°F
warm
85°F
hot
95°F
sweltering
The average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.
Kodiak Station, United States (3,627 miles away) is the far-away foreign place with temperatures most similar to Tromsø (view comparison). CloudsIn Tromsø, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year. The clearer part of the year in Tromsø begins around April 16 and lasts for 5.3 months, ending around September 27. The clearest month of the year in Tromsø is June, during which on average the sky is clear, mostly clear, or partly cloudy 42% of the time. The cloudier part of the year begins around September 27 and lasts for 6.7 months, ending around April 16. The cloudiest month of the year in Tromsø is December, during which on average the sky is overcast or mostly cloudy 79% of the time.
PrecipitationA wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Tromsø varies throughout the year. The wetter season lasts 5.3 months, from September 2 to February 11, with a greater than 41% chance of a given day being a wet day. The month with the most wet days in Tromsø is October, with an average of 14.8 days with at least 0.04 inches of precipitation. The drier season lasts 6.7 months, from February 11 to September 2. The month with the fewest wet days in Tromsø is May, with an average of 10.4 days with at least 0.04 inches of precipitation. Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation in Tromsø changes throughout the year. Rain alone is the most common for 9.0 months, from March 20 to December 19. The month with the most days of rain alone in Tromsø is September, with an average of 13.0 days. Snow alone is the most common for 3.0 months, from December 19 to March 20. The month with the most days of snow alone in Tromsø is January, with an average of 5.7 days.
RainfallTo show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Tromsø experiences significant seasonal variation in monthly rainfall. Rain falls throughout the year in Tromsø. The month with the most rain in Tromsø is October, with an average rainfall of 3.6 inches. The month with the least rain in Tromsø is March, with an average rainfall of 1.6 inches. Average Monthly Rainfall in Tromsø
The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average snowfall.
SnowfallAs with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Tromsø experiences extreme seasonal variation in monthly snowfall. The snowy period of the year lasts for 7.5 months, from September 28 to May 11, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Tromsø is January, with an average snowfall of 16.2 inches. The snowless period of the year lasts for 4.6 months, from May 11 to September 28. The least snow falls around July 30, with an average total accumulation of 0.0 inches. Average Monthly Snowfall in Tromsø
The average snowfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average rainfall.
SunDue to its extreme latitude, Tromsø experiences polar day (also known as the midnight Sun) during the summer and polar night during the winter. These are periods of time in which the sun is continuously above or below the horizon for more than one day. The precise start and end dates of polar day and night vary from year to year and depend on the precise location and elevation of the observer, and the local topography. In the summer in Tromsø during 2024, the Sun is continuously above the horizon for 2.3 months, rising at 1:06 AM on May 17, and not setting again until 12:24 AM on July 26. In the winter in Tromsø during 2024, the Sun is continuously below the horizon for 1.6 months, setting at 11:55 AM on November 26, and not rising again until 11:49 AM on January 15. Hours of Daylight and Twilight in Tromsø
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.
Daylight saving time (DST) is observed in Tromsø during 2024, starting in the spring on March 31, lasting 6.9 months, and ending in the fall on October 27. Sunrise & Sunset with Twilight and Daylight Saving Time in Tromsø
The solar day over the course of the year 2024. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray. The transitions to and from daylight saving time are indicated by the 'DST' labels.
The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation. Solar Elevation and Azimuth in Tromsø
northeastsouthwest
Solar elevation and azimuth over the course of the year 2024. The black lines are lines of constant solar elevation (the angle of the sun above the horizon, in degrees). The background color fills indicate the azimuth (the compass bearing) of the sun. The lightly tinted areas at the boundaries of the cardinal compass points indicate the implied intermediate directions (northeast, southeast, southwest, and northwest).
MoonThe figure below presents a compact representation of key lunar data for 2024. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases. HumidityWe base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night. The perceived humidity level in Tromsø, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.
WindThis section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages. The average hourly wind speed in Tromsø experiences significant seasonal variation over the course of the year. The windier part of the year lasts for 6.1 months, from October 21 to April 24, with average wind speeds of more than 8.1 miles per hour. The windiest month of the year in Tromsø is January, with an average hourly wind speed of 11.0 miles per hour. The calmer time of year lasts for 5.9 months, from April 24 to October 21. The calmest month of the year in Tromsø is July, with an average hourly wind speed of 5.3 miles per hour.
The predominant average hourly wind direction in Tromsø varies throughout the year. The wind is most often from the east for 2.6 weeks, from May 12 to May 30, with a peak percentage of 30% on May 20. The wind is most often from the west for 2.8 months, from May 30 to August 23, with a peak percentage of 34% on July 18. The wind is most often from the south for 8.6 months, from August 23 to May 12, with a peak percentage of 47% on January 1. Wind Direction in Tromsø
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).
Water TemperatureTromsø is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water. The average water temperature experiences some seasonal variation over the course of the year. The time of year with warmer water lasts for 2.4 months, from July 7 to September 20, with an average temperature above 49°F. The month of the year in Tromsø with the warmest water is August, with an average temperature of 51°F. The time of year with cooler water lasts for 4.0 months, from January 9 to May 11, with an average temperature below 41°F. The month of the year in Tromsø with the coolest water is March, with an average temperature of 39°F.
Best Time of Year to VisitTo characterize how pleasant the weather is in Tromsø throughout the year, we compute two travel scores. The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit Tromsø for general outdoor tourist activities is from mid July to mid August, with a peak score in the last week of July. Tourism Score in Tromsø
The tourism score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit Tromsø for hot-weather activities is from mid to late July. Beach/Pool Score in Tromsø
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
MethodologyFor each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed. Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies. Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more. Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter. Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter. Growing SeasonDefinitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere). The growing season in Tromsø typically lasts for 4.3 months (132 days), from around May 15 to around September 24, rarely starting before April 29 or after June 1, and rarely ending before September 3 or after October 13. Time Spent in Various Temperature Bands and the Growing Season in Tromsø
frigid
15°F
freezing
32°F
very cold
45°F
cold
55°F
cool
65°F
comfortable
75°F
warm
85°F
hot
95°F
sweltering
The percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.
Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F. Based on growing degree days alone, the first spring blooms in Tromsø should appear around July 2, only rarely appearing before June 16 or after July 23. Solar EnergyThis section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation. The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year. The brighter period of the year lasts for 2.6 months, from May 11 to July 29, with an average daily incident shortwave energy per square meter above 4.2 kWh. The brightest month of the year in Tromsø is June, with an average of 5.2 kWh. The darker period of the year lasts for 5.5 months, from September 29 to March 11, with an average daily incident shortwave energy per square meter below 1.1 kWh. The darkest month of the year in Tromsø is December, with an average of 0.0 kWh.
TopographyFor the purposes of this report, the geographical coordinates of Tromsø are 69.649 deg latitude, 18.955 deg longitude, and 46 ft elevation. The topography within 2 miles of Tromsø contains large variations in elevation, with a maximum elevation change of 1,982 feet and an average elevation above sea level of 209 feet. Within 10 miles contains large variations in elevation (4,003 feet). Within 50 miles also contains extreme variations in elevation (5,981 feet). The area within 2 miles of Tromsø is covered by trees (36%), artificial surfaces (36%), and water (17%), within 10 miles by trees (22%) and sparse vegetation (22%), and within 50 miles by water (43%) and trees (19%). Data SourcesThis report illustrates the typical weather in Tromsø, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016. Temperature and Dew PointThere are 4 weather stations near enough to contribute to our estimation of the temperature and dew point in Tromsø. For each station, the records are corrected for the elevation difference between that station and Tromsø according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations. The estimated value at Tromsø is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Tromsø and a given station. The stations contributing to this reconstruction are:
![]() To get a sense of how much these sources agree with each other, you can view a comparison of Tromsø and the stations that contribute to our estimates of its temperature history and climate. Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data. Other DataAll data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus. All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid. Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations. Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory. Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database . Time zones for airports and weather stations are provided by AskGeo.com . Maps are © OpenStreetMap contributors. DisclaimerThe information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site. We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands. We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader. Please review our full terms contained on our Terms of Service page. |