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Climate and Average Weather Year Round in Bessemer Pennsylvania, United States

In Bessemer, the summers are warm, humid, and partly cloudy and the winters are freezing, snowy, and mostly cloudy. Over the course of the year, the temperature typically varies from 19°F to 83°F and is rarely below 2°F or above 91°F.

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

Climate in Bessemer

very coldcoldcoolwarmcoolcoldvery coldJanFebMarAprMayJunJulAugSepOctNovDecNowNow65%65%29%29%clearovercastprecipitation: 3.4 inprecipitation: 3.4 in1.6 in1.6 inmuggy: 46%muggy: 46%0%0%drydrytourism score: 6.4tourism score: 6.40.10.1
Bessemer weather by month. Click on each chart for more information.

The warm season lasts for 3.7 months, from May 24 to September 16, with an average daily high temperature above 73°F. The hottest month of the year in Bessemer is July, with an average high of 83°F and low of 61°F.

The cold season lasts for 3.2 months, from November 30 to March 4, with an average daily high temperature below 43°F. The coldest month of the year in Bessemer is January, with an average low of 20°F and high of 34°F.

Average High and Low Temperature in Bessemer

Average High and Low Temperature in BessemerwarmcoldcoldJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FJan 2933°FJan 2933°FJul 1983°FJul 1983°F19°F19°F62°F62°FMay 2473°FMay 2473°FSep 1673°FSep 1673°FNov 3043°FNov 3043°FMar 443°FMar 443°F51°F51°F53°F53°F30°F30°F26°F26°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 34°F37°F48°F61°F71°F79°F83°F81°F73°F61°F49°F38°F
Temp. 26°F28°F37°F49°F59°F68°F72°F70°F63°F51°F41°F31°F
Low 20°F21°F29°F39°F49°F57°F61°F60°F53°F43°F34°F26°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 Bessemer

Average Hourly Temperature in BessemerJanFebMarAprMayJunJulAugSepOctNovDec12 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 AMNowNowfreezingvery coldvery coldcoldcoldcoolcomfortablewarmcomfortablefreezingfreezing
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.

Starokozache, Ukraine (5,051 miles away); Mineralnye Vody, Russia (5,598 miles); and Tegh, Armenia (5,957 miles) are the far-away foreign places with temperatures most similar to Bessemer (view comparison).

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In Bessemer, 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 Bessemer begins around May 13 and lasts for 5.9 months, ending around November 9.

The clearest month of the year in Bessemer is August, during which on average the sky is clear, mostly clear, or partly cloudy 65% of the time.

The cloudier part of the year begins around November 9 and lasts for 6.1 months, ending around May 13.

The cloudiest month of the year in Bessemer is January, during which on average the sky is overcast or mostly cloudy 70% of the time.

Cloud Cover Categories in Bessemer

Cloud Cover Categories in BessemerclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Aug 2665%Aug 2665%Jan 1329%Jan 1329%May 1347%May 1347%Nov 948%Nov 948%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 70%66%59%55%52%47%39%35%36%44%56%66%
Clearer 30%34%41%45%48%53%61%65%64%56%44%34%

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

The wetter season lasts 5.9 months, from March 27 to September 24, with a greater than 30% chance of a given day being a wet day. The month with the most wet days in Bessemer is June, with an average of 11.5 days with at least 0.04 inches of precipitation.

The drier season lasts 6.1 months, from September 24 to March 27. The month with the fewest wet days in Bessemer is January, with an average of 6.6 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 in Bessemer is June, with an average of 11.5 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 40% on June 14.

Daily Chance of Precipitation in Bessemer

Daily Chance of Precipitation in BessemerwetdrydryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jun 1440%Jun 1440%Jan 3019%Jan 3019%Mar 2730%Mar 2730%Sep 2430%Sep 2430%NowNowrainsnowmixed
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 3.4d3.3d6.6d9.3d11.1d11.5d11.0d9.9d8.8d7.9d6.8d5.1d
Mixed 1.4d1.6d1.4d0.4d0.0d0.0d0.0d0.0d0.0d0.1d0.6d1.4d
Snow 1.9d1.5d0.8d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.3d1.2d
Any 6.6d6.5d8.8d9.7d11.1d11.5d11.0d9.9d8.8d8.0d7.7d7.7d

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. Bessemer experiences significant seasonal variation in monthly rainfall.

Rain falls throughout the year in Bessemer. The month with the most rain in Bessemer is June, with an average rainfall of 3.4 inches.

The month with the least rain in Bessemer is February, with an average rainfall of 1.2 inches.

Average Monthly Rainfall in Bessemer

Average Monthly Rainfall in BessemerJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in1 in1 in2 in2 in3 in3 in4 in4 in5 in5 in6 in6 inJun 63.4 inJun 63.4 inFeb 51.1 inFeb 51.1 inSep 92.9 inSep 92.9 inNowNow
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 1.3″1.2″2.0″2.6″3.1″3.4″3.1″2.8″2.8″2.4″2.3″1.8″

Snowfall

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

The snowy period of the year lasts for 4.7 months, from November 14 to April 6, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Bessemer is February, with an average snowfall of 5.1 inches.

The snowless period of the year lasts for 7.3 months, from April 6 to November 14. The least snow falls around July 18, with an average total accumulation of 0.0 inches.

Average Monthly Snowfall in Bessemer

Average Monthly Snowfall in BessemersnowsnowJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in2 in2 in4 in4 in6 in6 in8 in8 in10 in10 in12 in12 inFeb 155.1 inFeb 155.1 inJul 180.0 inJul 180.0 inNov 141.0 inNov 141.0 inApr 61.0 inApr 61.0 in
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 4.6″5.1″3.3″0.4″0.0″0.0″0.0″0.0″0.0″0.1″1.1″3.8″

The length of the day in Bessemer varies significantly over the course of the year. In 2024, the shortest day is December 21, with 9 hours, 14 minutes of daylight; the longest day is June 20, with 15 hours, 8 minutes of daylight.

Hours of Daylight and Twilight in Bessemer

Hours of Daylight and Twilight in BessemerJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 8 minMar 1912 hr, 8 minMar 1915 hr, 8 minJun 2015 hr, 8 minJun 2012 hr, 11 minSep 2212 hr, 11 minSep 229 hr, 14 minDec 219 hr, 14 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 9.6h10.7h12.0h13.4h14.5h15.1h14.8h13.7h12.4h11.1h9.9h9.3h

The earliest sunrise is at 5:49 AM on June 14, and the latest sunrise is 2 hours, 5 minutes later at 7:54 AM on November 2. The earliest sunset is at 4:53 PM on December 7, and the latest sunset is 4 hours, 5 minutes later at 8:58 PM on June 27.

Daylight saving time (DST) is observed in Bessemer during 2024, starting in the spring on March 10, lasting 7.8 months, and ending in the fall on November 3.

Sunrise & Sunset with Twilight and Daylight Saving Time in Bessemer

Sunrise & Sunset with Twilight and Daylight Saving Time in BessemerJanFebMarAprMayJunJulAugSepOctNovDec2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 145:49 AMJun 145:49 AM8:58 PMJun 278:58 PMJun 27Dec 74:53 PMDec 74:53 PM7:54 AMNov 27:54 AMNov 2Mar 10DSTMar 10DSTDSTNov 3DSTNov 3daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
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 Bessemer

Solar Elevation and Azimuth in BessemerJanFebMarAprMayJunJulAugSepOctNovDec12 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 AM000101010102020203030304040505060607000010101020202020303040405050602672NowNow
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 Bessemer

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.

Bessemer experiences significant seasonal variation in the perceived humidity.

The muggier period of the year lasts for 3.9 months, from May 28 to September 23, during which time the comfort level is muggy, oppressive, or miserable at least 11% of the time. The month with the most muggy days in Bessemer is July, with 12.9 days that are muggy or worse.

The least muggy day of the year is February 21, when muggy conditions are essentially unheard of.

Humidity Comfort Levels in Bessemer

Humidity Comfort Levels in BessemermuggyJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Feb 210%Feb 210%Aug 146%Aug 146%May 2811%May 2811%Sep 2311%Sep 2311%NowNowoppressiveoppressivemuggymuggycomfortablecomfortabledrydryhumidhumid
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 0.0d0.0d0.0d0.0d1.8d7.6d12.9d12.8d5.6d0.5d0.0d0.0d

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 Bessemer experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 5.3 months, from November 14 to April 23, with average wind speeds of more than 5.0 miles per hour. The windiest month of the year in Bessemer is February, with an average hourly wind speed of 6.6 miles per hour.

The calmer time of year lasts for 6.7 months, from April 23 to November 14. The calmest month of the year in Bessemer is August, with an average hourly wind speed of 3.4 miles per hour.

Average Wind Speed in Bessemer

Average Wind Speed in BessemerwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph1 mph1 mph2 mph2 mph3 mph3 mph4 mph4 mph5 mph5 mph6 mph6 mph7 mph7 mph8 mph8 mph9 mph9 mph10 mph10 mphJan 316.7 mphJan 316.7 mphAug 33.4 mphAug 33.4 mphNov 145.0 mphNov 145.0 mphApr 235.0 mphApr 235.0 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) 6.56.66.15.34.33.83.53.43.84.45.05.7

The predominant average hourly wind direction in Bessemer varies throughout the year.

The wind is most often from the south for 4.0 weeks, from September 3 to October 1, with a peak percentage of 32% on September 23. The wind is most often from the west for 11 months, from October 1 to September 3, with a peak percentage of 48% on January 1.

Wind Direction in Bessemer

Wind Direction in BessemerWSWJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwestsouthnortheast
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 in Bessemer 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 Bessemer for general outdoor tourist activities is from mid June to mid September, with a peak score in the second week of August.

Tourism Score in Bessemer

Tourism Score in Bessemerbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.46.40.10.1NowNowtemperaturetemperature 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 Bessemer for hot-weather activities is from late June to mid August, with a peak score in the third week of July.

Beach/Pool Score in Bessemer

Beach/Pool Score in Bessemerbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810105.15.10.00.0NowNow 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 in Bessemer typically lasts for 5.3 months (162 days), from around May 3 to around October 12, rarely starting before April 13 or after May 25, and rarely ending before September 25 or after October 29.

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

Time Spent in Various Temperature Bands and the Growing Season in Bessemergrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%May 350%May 350%Oct 1250%Oct 1250%May 2590%May 2590%Sep 2590%Sep 2590%Apr 1310%Apr 1310%Oct 2910%Oct 2910%Jul 22100%Jul 22100%NowNowfrigidfreezingvery coldcoolcomfortablewarmcoldhot
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 Bessemer should appear around April 7, only rarely appearing before March 22 or after April 20.

Growing Degree Days in Bessemer

Growing Degree Days in BessemerJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F500°F500°F1,000°F1,000°F1,500°F1,500°F2,000°F2,000°F2,500°F2,500°F3,000°F3,000°FApr 789°FApr 789°FJun 21900°FJun 21900°FAug 31,800°FAug 31,800°FDec 312,966°FDec 312,966°F
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 3.8 months, from April 30 to August 25, with an average daily incident shortwave energy per square meter above 5.7 kWh. The brightest month of the year in Bessemer is June, with an average of 6.7 kWh.

The darker period of the year lasts for 3.4 months, from November 4 to February 14, with an average daily incident shortwave energy per square meter below 2.5 kWh. The darkest month of the year in Bessemer is December, with an average of 1.5 kWh.

Average Daily Incident Shortwave Solar Energy in Bessemer

Average Daily Incident Shortwave Solar Energy in BessemerbrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJun 306.8 kWhJun 306.8 kWhDec 221.5 kWhDec 221.5 kWhApr 305.7 kWhApr 305.7 kWhAug 255.7 kWhAug 255.7 kWhNov 42.5 kWhNov 42.5 kWhFeb 142.5 kWhFeb 142.5 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) 1.72.63.95.26.16.76.66.04.93.42.11.5

For the purposes of this report, the geographical coordinates of Bessemer are 40.975 deg latitude, -80.494 deg longitude, and 1,079 ft elevation.

The topography within 2 miles of Bessemer contains only modest variations in elevation, with a maximum elevation change of 272 feet and an average elevation above sea level of 1,140 feet. Within 10 miles contains only modest variations in elevation (610 feet). Within 50 miles contains significant variations in elevation (1,099 feet).

The area within 2 miles of Bessemer is covered by cropland (43%), artificial surfaces (28%), and trees (28%), within 10 miles by cropland (42%) and trees (30%), and within 50 miles by trees (52%) and cropland (33%).

This report illustrates the typical weather in Bessemer, 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 are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Bessemer.

For each station, the records are corrected for the elevation difference between that station and Bessemer 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 Bessemer is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Bessemer 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 Bessemer 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 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.