Average Weather at Svalbard Airport, Longyear Svalbard & Jan Mayen
At Svalbard Airport, Longyear, the summers are short, cold, and dry; the winters are long, frigid, snowy, and windy; and it is overcast year round. Over the course of the year, the temperature typically varies from 4°F to 48°F and is rarely below -18°F or above 54°F.
Based on the tourism score, the best time of year to visit Svalbard Airport, Longyear for warm-weather activities is from mid to late July.
The warm season lasts for 2.5 months, from June 17 to September 3, with an average daily high temperature above 41°F. The hottest day of the year is July 22, with an average high of 48°F and low of 42°F.
The cold season lasts for 5.0 months, from November 23 to April 21, with an average daily high temperature below 21°F. The coldest day of the year is February 18, with an average low of 4°F and high of 15°F.
Average High and Low Temperature
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
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
Big Sky, Montana, United States (3,626 miles away); Sŭngjibaegam, North Korea (3,750 miles); and Petropavlovsk-Kamchatsky, Russia (3,238 miles) are the far-away foreign places with temperatures most similar to Svalbard Airport, Longyear (view comparison).
At Svalbard Airport, Longyear, 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 at Svalbard Airport, Longyear begins around April 19 and lasts for 5.7 months, ending around October 11. On May 28, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 41% of the time, and overcast or mostly cloudy 59% of the time.
The cloudier part of the year begins around October 11 and lasts for 6.3 months, ending around April 19. On January 20, the cloudiest day of the year, the sky is overcast or mostly cloudy 92% of the time, and clear, mostly clear, or partly cloudy 8% of the time.
Cloud Cover Categories
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days at Svalbard Airport, Longyear varies throughout the year.
The wetter season lasts 8.2 months, from July 22 to March 29, with a greater than 18% chance of a given day being a wet day. The chance of a wet day peaks at 27% on September 25.
The drier season lasts 3.8 months, from March 29 to July 22. The smallest chance of a wet day is 9% on May 29.
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 at Svalbard Airport, Longyear changes throughout the year.
Snow alone is the most common for 7.0 months, from October 16 to May 18. The highest chance of a day with snow alone is 15% on January 5.
Rain alone is the most common for 5.0 months, from May 18 to October 16. The highest chance of a day with rain alone is 25% on September 2.
Daily Chance of Precipitation
To 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. Svalbard Airport, Longyear experiences some seasonal variation in monthly rainfall.
The rainy period of the year lasts for 5.8 months, from June 11 to December 5, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around September 13, with an average total accumulation of 1.5 inches.
The rainless period of the year lasts for 6.2 months, from December 5 to June 11. The least rain falls around April 9, with an average total accumulation of 0.2 inches.
Average Monthly Rainfall
We report snowfall in liquid-equivalent terms. The actual depth of new snowfall is typically between 5 and 10 times the liquid-equivalent amount, assuming the ground is frozen. Colder, drier snow tends to be on the higher end of that range and warmer, wetter snow on the lower end.
As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Svalbard Airport, Longyear experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 8.8 months, from September 11 to June 6, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around December 31, with an average total liquid-equivalent accumulation of 1.0 inches.
The snowless period of the year lasts for 3.2 months, from June 6 to September 11. The least snow falls around July 24, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
Due to its extreme latitude, Svalbard Airport, Longyear 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 at Svalbard Airport, Longyear during 2021, the Sun is continuously above the horizon for 4.2 months, rising at 1:27 AM on April 18, and not setting again until 12:24 AM on August 25.
In the winter at Svalbard Airport, Longyear during 2021, the Sun is continuously below the horizon for 3.6 months, setting at 1:36 PM on October 25, and not rising again until 11:48 AM on February 15.
Hours of Daylight and Twilight
Daylight saving time (DST) is observed at Svalbard Airport, Longyear during 2021, starting in the spring on March 28, lasting 7.1 months, and ending in the fall on October 31.
Sunrise & Sunset with Twilight and Daylight Saving Time
The figure below presents a compact representation of key lunar data for 2021. 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.
Moon Rise, Set & Phases
We 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 at Svalbard Airport, Longyear, 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.
Humidity Comfort Levels
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
This 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 at Svalbard Airport, Longyear experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 6.0 months, from October 19 to April 19, with average wind speeds of more than 10.5 miles per hour. The windiest day of the year is January 2, with an average hourly wind speed of 13.5 miles per hour.
The calmer time of year lasts for 6.0 months, from April 19 to October 19. The calmest day of the year is June 21, with an average hourly wind speed of 7.5 miles per hour.
Average Wind Speed
The predominant average hourly wind direction at Svalbard Airport, Longyear is from the east throughout the year.
Svalbard Airport, Longyear 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 1.7 months, from July 12 to September 2, with an average temperature above 38°F. The day of the year with the warmest water is August 5, with an average temperature of 39°F.
The time of year with cooler water lasts for 7.5 months, from October 23 to June 8, with an average temperature below 33°F. The day of the year with the coolest water is February 14, with an average temperature of 32°F.
Average Water Temperature
Best Time of Year to Visit
To characterize how pleasant the weather is at Svalbard Airport, Longyear 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 Svalbard Airport, Longyear for general outdoor tourist activities is from mid to late July.
The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F.
For 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.
Definitions 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 at Svalbard Airport, Longyear typically lasts for 3.0 months (92 days), from around June 8 to around September 8, rarely starting before May 23 or after June 25, and rarely ending before August 19 or after September 25.
Time Spent in Various Temperature Bands and the Growing Season
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
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.
Growing Degree Days
This 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 2.0 months, from May 14 to July 14, with an average daily incident shortwave energy per square meter above 4.7 kWh. The brightest day of the year is June 8, with an average of 5.9 kWh.
The darker period of the year lasts for 6.5 months, from September 12 to March 28, with an average daily incident shortwave energy per square meter below 1.2 kWh. The darkest day of the year is November 11, with an average of 0.0 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Svalbard Airport, Longyear are 78.246 deg latitude, 15.466 deg longitude, and 92 ft elevation.
The topography within 2 miles of Svalbard Airport, Longyear contains very significant variations in elevation, with a maximum elevation change of 1,552 feet and an average elevation above sea level of 355 feet. Within 10 miles contains very significant variations in elevation (3,438 feet). Within 50 miles also contains extreme variations in elevation (4,117 feet).
The area within 2 miles of Svalbard Airport, Longyear is covered by water (78%) and sparse vegetation (13%), within 10 miles by water (49%) and snow and glaciers (35%), and within 50 miles by snow and glaciers (60%) and water (28%).
This report illustrates the typical weather at Svalbard Airport, Longyear, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
Svalbard Airport, Longyear has a weather station that reported reliably enough during the analysis period that we have included it in our network. When available, historical temperature and dew point measurements are taken directly from this weather station. These records are obtained from NOAA's Integrated Surface Hourly data set, falling back on ICAO METAR records as required.There are no other weather stations in our network within 200 kilometers of this location. Consequently, in the case of missing or erroneous measurements from this station, we fall back on NASA's MERRA-2 modern-era reanalysis , adjusted according to typical seasonal and diurnal differences between this station and the wide-area MERRA-2 reconstructed values.
All 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 © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.
The 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.