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Climate and Average Weather Year Round at Cologne Bonn Airport North Rhine-Westphalia, Germany

At Cologne Bonn Airport, the summers are comfortable and partly cloudy and the winters are very cold, windy, and mostly cloudy. Over the course of the year, the temperature typically varies from 31°F to 76°F and is rarely below 19°F or above 87°F.

Based on the tourism score, the best time of year to visit Cologne Bonn Airport for warm-weather activities is from mid June to early September.

Climate at Cologne Bonn Airport

very coldcoldcoolcomfortablewarmcomfortablecoolcoldJanFebMarAprMayJunJulAugSepOctNovDecNowNow57%57%27%27%overcastclearprecipitation: 2.3 inprecipitation: 2.3 in1.6 in1.6 inmuggy: 3%muggy: 3%0%0%drydrytourism score: 6.7tourism score: 6.70.10.1
Cologne Bonn Airport weather by month. Click on each chart for more information.

The warm season lasts for 3.2 months, from June 2 to September 8, with an average daily high temperature above 69°F. The hottest month of the year at Cologne Bonn Airport is July, with an average high of 75°F and low of 56°F.

The cold season lasts for 3.7 months, from November 16 to March 6, with an average daily high temperature below 48°F. The coldest month of the year at Cologne Bonn Airport is January, with an average low of 32°F and high of 42°F.

Average High and Low Temperature at Cologne Bonn Airport

Average High and Low Temperature at Cologne Bonn AirportwarmcoldcoldJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FFeb 843°FFeb 843°FAug 476°FAug 476°F31°F31°F57°F57°FJun 269°FJun 269°FSep 869°FSep 869°FNov 1648°FNov 1648°FMar 648°FMar 648°F50°F50°F52°F52°F38°F38°F34°F34°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 42°F44°F51°F59°F66°F71°F75°F74°F67°F59°F49°F43°F
Temp. 37°F38°F44°F50°F57°F62°F66°F65°F59°F52°F44°F39°F
Low 32°F32°F36°F41°F47°F53°F56°F55°F50°F45°F38°F34°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 at Cologne Bonn Airport

Average Hourly Temperature at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec12 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 AMNowNowvery coldvery coldcoldcoldcoolcomfortable
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.

Coquitlam, British Columbia, Canada (4,917 miles away) is the far-away foreign place with temperatures most similar to Cologne Bonn Airport (view comparison).

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At Cologne Bonn Airport, 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 Cologne Bonn Airport begins around March 22 and lasts for 6.6 months, ending around October 10.

The clearest month of the year at Cologne Bonn Airport is July, during which on average the sky is clear, mostly clear, or partly cloudy 56% of the time.

The cloudier part of the year begins around October 10 and lasts for 5.4 months, ending around March 22.

The cloudiest month of the year at Cologne Bonn Airport is December, during which on average the sky is overcast or mostly cloudy 72% of the time.

Cloud Cover Categories at Cologne Bonn Airport

Cloud Cover Categories at Cologne Bonn AirportclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jul 2157%Jul 2157%Dec 2527%Dec 2527%Mar 2242%Mar 2242%Oct 1042%Oct 1042%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 67%62%60%55%54%49%44%45%50%60%70%72%
Clearer 33%38%40%45%46%51%56%55%50%40%30%28%

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

The wetter season lasts 8.4 months, from May 8 to January 20, with a greater than 31% chance of a given day being a wet day. The month with the most wet days at Cologne Bonn Airport is December, with an average of 10.6 days with at least 0.04 inches of precipitation.

The drier season lasts 3.6 months, from January 20 to May 8. The month with the fewest wet days at Cologne Bonn Airport is March, with an average of 8.3 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. The month with the most days of rain alone at Cologne Bonn Airport is July, with an average of 10.4 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 35% on July 11.

Daily Chance of Precipitation at Cologne Bonn Airport

Daily Chance of Precipitation at Cologne Bonn AirportwetwetdryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Dec 2236%Dec 2236%Mar 325%Mar 325%May 831%May 831%Jan 2031%Jan 2031%NowNowrain
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 8.8d7.7d8.1d8.2d9.5d9.7d10.4d9.4d8.7d9.0d8.7d9.7d
Mixed 0.5d0.4d0.2d0.1d0.0d0.0d0.0d0.0d0.0d0.0d0.2d0.5d
Snow 0.4d0.1d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.1d0.4d
Any 9.7d8.2d8.3d8.3d9.5d9.7d10.4d9.4d8.7d9.0d9.0d10.6d

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. Cologne Bonn Airport experiences some seasonal variation in monthly rainfall.

Rain falls throughout the year at Cologne Bonn Airport. The month with the most rain at Cologne Bonn Airport is June, with an average rainfall of 2.2 inches.

The month with the least rain at Cologne Bonn Airport is April, with an average rainfall of 1.6 inches.

Average Monthly Rainfall at Cologne Bonn Airport

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 2.0″1.7″1.6″1.6″2.0″2.2″2.2″2.1″2.1″1.9″1.9″2.2″

Snowfall

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

The snowy period of the year lasts for 3.5 weeks, from December 20 to January 14, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow at Cologne Bonn Airport is January, with an average snowfall of 0.9 inches.

The snowless period of the year lasts for 11 months, from January 14 to December 20. The least snow falls around July 27, with an average total accumulation of 0.0 inches.

Average Monthly Snowfall at Cologne Bonn Airport

Average Monthly Snowfall at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in1 in1 in2 in2 in3 in3 in4 in4 inJan 31.1 inJan 31.1 inJul 270.0 inJul 270.0 inDec 201.0 inDec 201.0 inNowNow
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 0.9″0.4″0.2″0.0″0.0″0.0″0.0″0.0″0.0″0.0″0.2″0.9″

The length of the day at Cologne Bonn Airport varies extremely over the course of the year. In 2024, the shortest day is December 21, with 7 hours, 56 minutes of daylight; the longest day is June 20, with 16 hours, 32 minutes of daylight.

Hours of Daylight and Twilight at Cologne Bonn Airport

Hours of Daylight and Twilight at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 8 minMar 2012 hr, 8 minMar 2016 hr, 32 minJun 2016 hr, 32 minJun 2012 hr, 11 minSep 2212 hr, 11 minSep 227 hr, 56 minDec 217 hr, 56 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 8.5h10.0h11.9h13.9h15.6h16.4h16.0h14.5h12.6h10.7h8.9h8.0h

The earliest sunrise is at 5:17 AM on June 17, and the latest sunrise is 3 hours, 17 minutes later at 8:34 AM on December 30. The earliest sunset is at 4:25 PM on December 12, and the latest sunset is 5 hours, 24 minutes later at 9:49 PM on June 24.

Daylight saving time (DST) is observed at Cologne Bonn Airport 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 at Cologne Bonn Airport

Sunrise & Sunset with Twilight and Daylight Saving Time at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 175:17 AMJun 175:17 AM9:49 PMJun 249:49 PMJun 24Dec 124:25 PMDec 124:25 PM8:34 AMDec 308:34 AMDec 30Mar 31DSTMar 31DSTDSTOct 27DSTOct 27daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunriseSunset
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 at Cologne Bonn Airport

Solar Elevation and Azimuth at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec12 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 AM0000101010202030304040500001010101020203030404050601663NowNow
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 at Cologne Bonn Airport

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 at Cologne Bonn Airport, 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, staying within 1% of 1% throughout.

Humidity Comfort Levels at Cologne Bonn Airport

Humidity Comfort Levels at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Mar 50%Mar 50%Jul 133%Jul 133%NowNowhumidhumidcomfortablecomfortabledrydry
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 0.0d0.0d0.0d0.0d0.0d0.4d0.7d0.6d0.1d0.0d0.0d0.0d

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 at Cologne Bonn Airport experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 5.6 months, from October 17 to April 3, with average wind speeds of more than 10.2 miles per hour. The windiest month of the year at Cologne Bonn Airport is January, with an average hourly wind speed of 12.2 miles per hour.

The calmer time of year lasts for 6.4 months, from April 3 to October 17. The calmest month of the year at Cologne Bonn Airport is August, with an average hourly wind speed of 8.4 miles per hour.

Average Wind Speed at Cologne Bonn Airport

Average Wind Speed at Cologne Bonn AirportwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph2 mph2 mph4 mph4 mph6 mph6 mph8 mph8 mph10 mph10 mph12 mph12 mph14 mph14 mph16 mph16 mph18 mph18 mph20 mph20 mphJan 1712.3 mphJan 1712.3 mphAug 48.1 mphAug 48.1 mphOct 1710.2 mphOct 1710.2 mphApr 310.2 mphApr 310.2 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) 12.211.510.89.58.88.68.68.49.110.110.711.5

The predominant average hourly wind direction at Cologne Bonn Airport varies throughout the year.

The wind is most often from the west for 8.4 months, from January 18 to September 30, with a peak percentage of 46% on July 6. The wind is most often from the south for 3.6 months, from September 30 to January 18, with a peak percentage of 41% on January 1.

Wind Direction at Cologne Bonn Airport

Wind Direction at Cologne Bonn AirportSWSJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwestsoutheastnorth
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).

To characterize how pleasant the weather is at Cologne Bonn Airport 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 Cologne Bonn Airport for general outdoor tourist activities is from mid June to early September, with a peak score in the first week of August.

Tourism Score at Cologne Bonn Airport

Tourism Score at Cologne Bonn Airportbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.76.70.10.1NowNowtemperaturetemperature cloudscloudsprecipitationprecipitationtourism score
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 Cologne Bonn Airport for hot-weather activities is from early July to mid August, with a peak score in the first week of August.

Beach/Pool Score at Cologne Bonn Airport

Beach/Pool Score at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec002244668810104.14.10.00.0NowNow cloudscloudsprecipitationprecipitationbeach/pool score
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 at Cologne Bonn Airport typically lasts for 6.5 months (198 days), from around April 18 to around November 2, rarely starting before April 1 or after May 6, and rarely ending before October 12 or after November 29.

Time Spent in Various Temperature Bands and the Growing Season at Cologne Bonn Airport

Time Spent in Various Temperature Bands and the Growing Season at Cologne Bonn Airportgrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%50%Apr 1850%Apr 1850%Nov 250%Nov 290%May 690%May 690%Oct 1290%Oct 1210%Apr 110%Apr 110%Nov 2910%Nov 290%Dec 310%Dec 31Jul 26100%Jul 26100%freezingvery coldcoldcoolcomfortablewarmfrigid
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 at Cologne Bonn Airport should appear around April 13, only rarely appearing before March 28 or after April 28.

Growing Degree Days at Cologne Bonn Airport

Growing Degree Days at Cologne Bonn AirportJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F500°F500°F1,000°F1,000°F1,500°F1,500°F2,000°F2,000°FApr 1390°FApr 1390°FJul 7900°FJul 7900°FSep 61,800°FSep 61,800°FDec 312,178°FDec 312,178°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 3.6 months, from April 30 to August 17, with an average daily incident shortwave energy per square meter above 5.3 kWh. The brightest month of the year at Cologne Bonn Airport is June, with an average of 6.3 kWh.

The darker period of the year lasts for 3.7 months, from October 26 to February 17, with an average daily incident shortwave energy per square meter below 1.8 kWh. The darkest month of the year at Cologne Bonn Airport is December, with an average of 0.7 kWh.

Average Daily Incident Shortwave Solar Energy at Cologne Bonn Airport

Average Daily Incident Shortwave Solar Energy at Cologne Bonn AirportbrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJun 256.4 kWhJun 256.4 kWhDec 200.7 kWhDec 200.7 kWhApr 305.3 kWhApr 305.3 kWhAug 175.3 kWhAug 175.3 kWhOct 261.8 kWhOct 261.8 kWhFeb 171.8 kWhFeb 171.8 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) 0.91.83.04.65.86.36.25.33.82.31.10.7

For the purposes of this report, the geographical coordinates of Cologne Bonn Airport are 50.879 deg latitude, 7.123 deg longitude, and 236 ft elevation.

The topography within 2 miles of Cologne Bonn Airport contains only modest variations in elevation, with a maximum elevation change of 236 feet and an average elevation above sea level of 234 feet. Within 10 miles contains only modest variations in elevation (791 feet). Within 50 miles contains significant variations in elevation (3,143 feet).

The area within 2 miles of Cologne Bonn Airport is covered by trees (46%) and artificial surfaces (43%), within 10 miles by artificial surfaces (39%) and cropland (23%), and within 50 miles by trees (34%) and cropland (31%).

This report illustrates the typical weather at Cologne Bonn Airport, 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

Cologne Bonn Airport 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.

In the case of missing or erroneous measurements from this station, we fall back on records from nearby stations, adjusted according to typical seasonal and diurnal intra-station differences. For a given day of the year and hour of the day, the fallback station is selected to minimize the prediction error over the years for which there are measurements for both stations.

The stations on which we may fall back include but are not limited to Nörvenich Air Base, Mendig, Düsseldorf International Airport, Buechel, Frankfurt-Hahn Airport, Spangdahlem Air Base, Elsenborn-Butgenbach Air Base, and RAF Bruggen.

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.