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Climate and Average Weather Year Round in Longyearbyen Svalbard & Jan Mayen

In Longyearbyen, the summers are short, very 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 3°F to 47°F and is rarely below -19°F or above 53°F.

Based on the tourism score, the best time of year to visit Longyearbyen for warm-weather activities is from mid to late July.

Climate in Longyearbyen

frigidfreezingvery coldcoldvery coldfreezingJanFebMarAprMayJunJulAugSepOctNovDecNowNow40%40%8%8%overcastprecipitation: 1.6 inprecipitation: 1.6 in0.5 in0.5 inmuggy: 0%muggy: 0%drydrytourism score: 0.2tourism score: 0.20.00.0
Longyearbyen weather by month. Click on each chart for more information.

The warm season lasts for 2.5 months, from June 17 to September 2, with an average daily high temperature above 40°F. The hottest month of the year in Longyearbyen is July, with an average high of 46°F and low of 40°F.

The cold season lasts for 5.0 months, from November 22 to April 20, with an average daily high temperature below 20°F. The coldest month of the year in Longyearbyen is February, with an average low of 3°F and high of 14°F.

Average High and Low Temperature in Longyearbyen

Average High and Low Temperature in LongyearbyenwarmcoldcoldJanFebMarAprMayJunJulAugSepOctNovDec-20°F-20°F-10°F-10°F0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FFeb 1814°FFeb 1814°FJul 2147°FJul 2147°F3°F3°F41°F41°FJun 1740°FJun 1740°FSep 240°FSep 240°FNov 2220°FNov 2220°FApr 2020°FApr 2020°F35°F35°F35°F35°F12°F12°F10°F10°FNowNow
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.
AverageJanFebMarAprMayJunJulAugSepOctNovDec
High 15°F14°F14°F19°F30°F40°F46°F44°F37°F27°F21°F17°F
Temp. 10°F9°F9°F14°F27°F37°F44°F42°F34°F23°F17°F12°F
Low 5°F3°F3°F9°F23°F35°F40°F38°F31°F19°F12°F7°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 Longyearbyen

Average Hourly Temperature in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMNowNowfrigidfrigidfreezingfreezingvery coldcold
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.

Big Sky, Montana, United States (3,629 miles away); Sŭngjibaegam, North Korea (3,749 miles); and Sinegorsk, Russia (3,500 miles) are the far-away foreign places with temperatures most similar to Longyearbyen (view comparison).

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In Longyearbyen, 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 Longyearbyen begins around April 19 and lasts for 5.7 months, ending around October 10.

The clearest month of the year in Longyearbyen is June, during which on average the sky is clear, mostly clear, or partly cloudy 38% of the time.

The cloudier part of the year begins around October 10 and lasts for 6.3 months, ending around April 19.

The cloudiest month of the year in Longyearbyen is January, during which on average the sky is overcast or mostly cloudy 92% of the time.

Cloud Cover Categories in Longyearbyen

Cloud Cover Categories in LongyearbyenclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%May 2740%May 2740%Jan 208%Jan 208%Apr 1923%Apr 1923%Oct 1024%Oct 1024%NowNowclearmostly clearpartly cloudymostly cloudyovercast
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.
FractionJanFebMarAprMayJunJulAugSepOctNovDec
Cloudier 92%92%88%78%64%62%69%72%74%78%86%90%
Clearer 8%8%12%22%36%38%31%28%26%22%14%10%

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Longyearbyen varies throughout the year.

The wetter season lasts 8.9 months, from July 21 to April 17, with a greater than 18% chance of a given day being a wet day. The month with the most wet days in Longyearbyen is September, with an average of 7.7 days with at least 0.04 inches of precipitation.

The drier season lasts 3.1 months, from April 17 to July 21. The month with the fewest wet days in Longyearbyen is May, with an average of 3.5 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 Longyearbyen changes throughout the year.

Snow alone is the most common for 7.2 months, from October 12 to May 18. The month with the most days of snow alone in Longyearbyen is January, with an average of 4.9 days.

Rain alone is the most common for 4.8 months, from May 18 to October 12. The month with the most days of rain alone in Longyearbyen is August, with an average of 6.4 days.

Daily Chance of Precipitation in Longyearbyen

Daily Chance of Precipitation in LongyearbyensnowrainsnowJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Sep 2427%Sep 2427%May 289%May 289%Jul 2118%Jul 2118%Apr 1718%Apr 1718%NowNowsnowrainmixed
The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).
Days ofJanFebMarAprMayJunJulAugSepOctNovDec
Rain 0.8d0.6d0.6d0.6d1.3d3.4d5.3d6.4d6.1d2.5d1.2d0.8d
Mixed 1.5d1.3d1.2d0.9d0.7d0.2d0.0d0.1d0.8d1.6d1.7d1.6d
Snow 4.9d4.1d4.7d3.6d1.5d0.2d0.0d0.0d0.8d3.3d4.1d4.6d
Any 7.2d6.1d6.5d5.1d3.5d3.8d5.4d6.5d7.7d7.4d7.0d7.0d

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. Longyearbyen experiences some seasonal variation in monthly rainfall.

The rainy period of the year lasts for 5.2 months, from June 11 to November 17, with a sliding 31-day rainfall of at least 0.5 inches. The month with the most rain in Longyearbyen is September, with an average rainfall of 1.4 inches.

The rainless period of the year lasts for 6.8 months, from November 17 to June 11. The month with the least rain in Longyearbyen is April, with an average rainfall of 0.2 inches.

Average Monthly Rainfall in Longyearbyen

Average Monthly Rainfall in LongyearbyenrainJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in2 in2 in4 in4 in6 in6 in8 in8 in10 in10 in12 in12 inSep 111.4 inSep 111.4 inApr 80.2 inApr 80.2 inJan 70.4 inJan 70.4 inDec 180.4 inDec 180.4 inJun 110.5 inJun 110.5 in
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.
JanFebMarAprMayJunJulAugSepOctNovDec
Rainfall 0.4″0.3″0.2″0.2″0.3″0.6″0.9″1.2″1.4″0.8″0.5″0.4″

Snowfall

As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Longyearbyen experiences extreme seasonal variation in monthly snowfall.

The snowy period of the year lasts for 9.0 months, from September 7 to June 8, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Longyearbyen is December, with an average snowfall of 10.0 inches.

The snowless period of the year lasts for 3.0 months, from June 8 to September 7. The least snow falls around July 24, with an average total accumulation of 0.0 inches.

Average Monthly Snowfall in Longyearbyen

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.
JanFebMarAprMayJunJulAugSepOctNovDec
Snowfall 9.8″9.0″9.7″6.9″3.2″0.6″0.0″0.1″1.9″7.3″9.3″10.0″

Due to its extreme latitude, Longyearbyen 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 Longyearbyen during 2024, the Sun is continuously above the horizon for 4.2 months, rising at 1:10 AM on April 18, and not setting again until 12:10 AM on August 25.

In the winter in Longyearbyen during 2024, the Sun is continuously below the horizon for 3.7 months, setting at 1:29 PM on October 25, and not rising again until 11:30 AM on February 16.

Hours of Daylight and Twilight in Longyearbyen

Hours of Daylight and Twilight in Longyearbyenpolar daypolar nightpolar nightJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 22 minMar 2012 hr, 22 minMar 2024 hr, 0 minJun 2024 hr, 0 minJun 2012 hr, 34 minSep 2212 hr, 34 minSep 220 minDec 210 minDec 21nightnightdayNowNow
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.
Hours ofJanFebMarAprMayJunJulAugSepOctNovDec
Daylight 0.0h2.4h11.6h20.9h24.0h24.0h24.0h23.1h14.3h5.4h0.0h0.0h

Daylight saving time (DST) is observed in Longyearbyen 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 Longyearbyen

Sunrise & Sunset with Twilight and Daylight Saving Time in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMApr 181:10 AMApr 181:10 AM12:10 AMAug 2412:10 AMAug 241:29 PMOct 251:29 PMOct 25Feb 1611:30 AMFeb 1611:30 AMMar 31DSTMar 31DSTdaynightnightnightnightSolarMidnightSolarMidnightSolarNoonNowNow
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 Longyearbyen

Solar Elevation and Azimuth in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AM1010203001010202030-1235NowNow
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).

The 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.

Moon Rise, Set & Phases in Longyearbyen

The time in which the moon is above the horizon (light blue area), with new moons (dark gray lines) and full moons (blue lines) indicated. The shaded overlays indicate night and civil twilight.

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 in Longyearbyen, 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 in Longyearbyen

Humidity Comfort Levels in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jul 20%Jul 20%NowNowdrydry
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.
JanFebMarAprMayJunJulAugSepOctNovDec
Muggy days 0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d

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 in Longyearbyen experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 6.0 months, from October 18 to April 18, with average wind speeds of more than 10.4 miles per hour. The windiest month of the year in Longyearbyen is January, with an average hourly wind speed of 13.1 miles per hour.

The calmer time of year lasts for 6.0 months, from April 18 to October 18. The calmest month of the year in Longyearbyen is July, with an average hourly wind speed of 7.6 miles per hour.

Average Wind Speed in Longyearbyen

Average Wind Speed in LongyearbyenwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph5 mph5 mph10 mph10 mph15 mph15 mph20 mph20 mphJan 213.3 mphJan 213.3 mphJun 207.4 mphJun 207.4 mphOct 1810.4 mphOct 1810.4 mphApr 1810.4 mphApr 1810.4 mphNowNow
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Wind Speed (mph) 13.112.511.810.58.77.67.67.78.810.211.312.6

The predominant average hourly wind direction in Longyearbyen is from the east throughout the year.

Wind Direction in Longyearbyen

Wind Direction in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwesteastnorthsouth
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).

Longyearbyen 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 11 to September 1, with an average temperature above 38°F. The month of the year in Longyearbyen with the warmest water is August, with an average temperature of 39°F.

The time of year with cooler water lasts for 7.5 months, from October 22 to June 7, with an average temperature below 33°F. The month of the year in Longyearbyen with the coolest water is February, with an average temperature of 32°F.

Average Water Temperature in Longyearbyen

Average Water Temperature in LongyearbyenwarmcoolcoolJanFebMarAprMayJunJulAugSepOctNovDec28°F28°F30°F30°F32°F32°F34°F34°F36°F36°F38°F38°F40°F40°F42°F42°F44°F44°FAug 539°FAug 539°F32°FFeb 1432°FFeb 14Sep 138°FSep 138°FOct 2233°FOct 2233°FJun 733°FJun 733°FNowNow
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 32°F32°F32°F32°F32°F34°F38°F39°F37°F34°F32°F32°F

To characterize how pleasant the weather is in Longyearbyen 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 Longyearbyen for general outdoor tourist activities is from mid to late July.

Tourism Score in Longyearbyen

Tourism Score in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec002244668810100.20.20.00.0NowNowtemperaturetemperaturecloudscloudsprecipitationprecipitation
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.

Beach/Pool Score in Longyearbyen

Beach/Pool Score in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec002244668810100.00.0NowNow cloudscloudsprecipitationprecipitation
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).

Methodology

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 in Longyearbyen typically lasts for 2.5 months (76 days), from around June 13 to around August 29, rarely starting before May 28 or after June 30, and rarely ending before August 9 or after September 16.

Time Spent in Various Temperature Bands and the Growing Season in Longyearbyen

Time Spent in Various Temperature Bands and the Growing Season in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jun 1350%Jun 1350%Aug 2950%Aug 2950%Jun 3090%Jun 3090%Aug 990%Aug 990%May 2810%May 2810%Sep 1610%Sep 1610%0%Nov 160%Nov 16Jul 16100%Jul 16100%NowNowfrigidfreezingvery coldcold
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.

Growing Degree Days in Longyearbyen

Growing Degree Days in LongyearbyenJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F2°F2°F4°F4°F6°F6°F8°F8°F10°F10°F12°F12°F14°F14°F16°F16°F18°F18°FDec 319°FDec 319°FNowNow
The average growing degree days accumulated over the course of the year, with 25th to 75th and 10th to 90th percentile bands.

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 13 to July 13, with an average daily incident shortwave energy per square meter above 4.7 kWh. The brightest month of the year in Longyearbyen is June, with an average of 5.8 kWh.

The darker period of the year lasts for 6.5 months, from September 11 to March 27, with an average daily incident shortwave energy per square meter below 1.2 kWh. The darkest month of the year in Longyearbyen is January, with an average of 0.0 kWh.

Average Daily Incident Shortwave Solar Energy in Longyearbyen

Average Daily Incident Shortwave Solar Energy in LongyearbyenbrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJun 75.9 kWhJun 75.9 kWhJan 10.0 kWhJan 10.0 kWhSep 111.2 kWhSep 111.2 kWhMar 271.2 kWhMar 271.2 kWhNowNow
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Solar Energy (kWh) 0.00.00.72.64.95.84.52.71.00.10.00.0

For the purposes of this report, the geographical coordinates of Longyearbyen are 78.223 deg latitude, 15.647 deg longitude, and 20 ft elevation.

The topography within 2 miles of Longyearbyen contains very significant variations in elevation, with a maximum elevation change of 1,594 feet and an average elevation above sea level of 358 feet. Within 10 miles contains very significant variations in elevation (3,448 feet). Within 50 miles also contains extreme variations in elevation (4,160 feet).

The area within 2 miles of Longyearbyen is covered by snow and glaciers (36%), water (35%), and sparse vegetation (25%), within 10 miles by snow and glaciers (50%) and water (30%), and within 50 miles by snow and glaciers (60%) and water (28%).

This report illustrates the typical weather in Longyearbyen, 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

There is only a single weather station, Svalbard Airport, Longyear, in our network suitable to be used as a proxy for the historical temperature and dew point records of Longyearbyen.

At a distance of 5 kilometers from Longyearbyen, closer than our threshold of 150 kilometers, this station is deemed sufficiently nearby to be relied upon as our primary source for temperature and dew point records.

The station records are corrected for the elevation difference between the station and Longyearbyen according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.

Please note that the station records themselves may additionally have been back-filled using other nearby stations or the MERRA-2 reanalysis.

Other Data

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 © OpenStreetMap contributors.

Disclaimer

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.

Please review our full terms contained on our Terms of Service page.