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Climate and Average Weather Year Round in Iwaki Japan

In Iwaki, the summers are short, warm, muggy, wet, and mostly cloudy and the winters are very cold, windy, and mostly clear. Over the course of the year, the temperature typically varies from 30°F to 81°F and is rarely below 23°F or above 88°F.

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

Climate in Iwaki

very coldcoldcoolcomfortablewarmcoolcoldJanFebMarAprMayJunJulAugSepOctNovDecNowNow71%71%30%30%clearovercastprecipitation: 6.5 inprecipitation: 6.5 in1.5 in1.5 inmuggy: 90%muggy: 90%0%0%drydrytourism score: 6.5tourism score: 6.50.00.0
Iwaki weather by month. Click on each chart for more information.

The warm season lasts for 2.8 months, from June 28 to September 21, with an average daily high temperature above 74°F. The hottest month of the year in Iwaki is August, with an average high of 80°F and low of 71°F.

The cold season lasts for 3.4 months, from December 7 to March 19, with an average daily high temperature below 51°F. The coldest month of the year in Iwaki is January, with an average low of 31°F and high of 44°F.

Average High and Low Temperature in Iwaki

Average High and Low Temperature in IwakiwarmcoldcoldJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FJan 2644°FJan 2644°FAug 881°FAug 881°F30°F30°F72°F72°FJun 2874°FJun 2874°FSep 2174°FSep 2174°FDec 751°FDec 751°FMar 1951°FMar 1951°F65°F65°F63°F63°F37°F37°F37°F37°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 44°F45°F51°F59°F66°F71°F77°F80°F75°F67°F58°F49°F
Temp. 37°F37°F43°F52°F60°F66°F72°F76°F70°F60°F50°F41°F
Low 31°F31°F37°F46°F55°F62°F69°F71°F65°F54°F43°F35°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 Iwaki

Average Hourly Temperature in IwakiJanFebMarAprMayJunJulAugSepOctNovDec12 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 coldcoldcoldcoolcoolcomfortablewarmvery cold
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.

Avalon, New Jersey, United States (6,716 miles away) and Hayrat, Turkey (5,083 miles) are the far-away foreign places with temperatures most similar to Iwaki (view comparison).

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In Iwaki, 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 Iwaki begins around October 7 and lasts for 5.7 months, ending around March 30.

The clearest month of the year in Iwaki is December, during which on average the sky is clear, mostly clear, or partly cloudy 69% of the time.

The cloudier part of the year begins around March 30 and lasts for 6.3 months, ending around October 7.

The cloudiest month of the year in Iwaki is June, during which on average the sky is overcast or mostly cloudy 66% of the time.

Cloud Cover Categories in Iwaki

Cloud Cover Categories in IwakiclearerclearercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Dec 2671%Dec 2671%Jul 230%Jul 230%Oct 750%Oct 750%Mar 3051%Mar 3051%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 33%39%46%53%58%66%66%57%56%44%36%31%
Clearer 67%61%54%47%42%34%34%43%44%56%64%69%

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

The wetter season lasts 5.3 months, from May 1 to October 11, with a greater than 32% chance of a given day being a wet day. The month with the most wet days in Iwaki is July, with an average of 13.0 days with at least 0.04 inches of precipitation.

The drier season lasts 6.7 months, from October 11 to May 1. The month with the fewest wet days in Iwaki is January, with an average of 4.4 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. The month with the most days of rain alone in Iwaki is July, with an average of 13.0 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 50% on July 1.

Daily Chance of Precipitation in Iwaki

Daily Chance of Precipitation in IwakiwetdrydryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jul 150%Jul 150%Dec 2113%Dec 2113%May 132%May 132%Oct 1132%Oct 1132%NowNowrainmixed
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 4.1d5.1d8.4d9.2d9.8d12.4d13.0d10.9d12.0d9.2d6.4d4.6d
Mixed 0.4d0.5d0.2d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.1d
Any 4.4d5.5d8.6d9.2d9.8d12.4d13.0d10.9d12.0d9.2d6.4d4.6d

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. Iwaki experiences extreme seasonal variation in monthly rainfall.

Rain falls throughout the year in Iwaki. The month with the most rain in Iwaki is September, with an average rainfall of 6.4 inches.

The month with the least rain in Iwaki is January, with an average rainfall of 1.5 inches.

Average Monthly Rainfall in Iwaki

Average Monthly Rainfall in IwakiJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in2 in2 in4 in4 in6 in6 in8 in8 in10 in10 in12 in12 inSep 206.5 inSep 206.5 inDec 311.5 inDec 311.5 inJul 25.8 inJul 25.8 inAug 74.4 inAug 74.4 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 1.5″2.0″3.1″4.0″4.1″5.0″5.3″4.7″6.4″4.9″2.7″1.7″

The length of the day in Iwaki varies significantly over the course of the year. In 2024, the shortest day is December 21, with 9 hours, 37 minutes of daylight; the longest day is June 21, with 14 hours, 43 minutes of daylight.

Hours of Daylight and Twilight in Iwaki

Hours of Daylight and Twilight in IwakiJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 8 minMar 2012 hr, 8 minMar 2014 hr, 43 minJun 2114 hr, 43 minJun 2112 hr, 9 minSep 2212 hr, 9 minSep 229 hr, 37 minDec 219 hr, 37 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 9.9h10.8h12.0h13.2h14.2h14.7h14.4h13.5h12.4h11.2h10.2h9.7h

The earliest sunrise is at 4:16 AM on June 13, and the latest sunrise is 2 hours, 34 minutes later at 6:50 AM on January 7. The earliest sunset is at 4:19 PM on December 6, and the latest sunset is 2 hours, 41 minutes later at 7:00 PM on June 29.

Daylight saving time (DST) is not observed in Iwaki during 2024.

Sunrise & Sunset with Twilight in Iwaki

Sunrise & Sunset with Twilight in IwakiJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PMJun 134:16 AMJun 134:16 AM7:00 PMJun 297:00 PMJun 29Dec 64:19 PMDec 64:19 PM6:50 AMJan 76:50 AMJan 7daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
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 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 Iwaki

Solar Elevation and Azimuth in IwakiJanFebMarAprMayJunJulAugSepOctNovDec12 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 AM000010101010202020203030303040404050505060607000001010101020202020303030404040505060703076NowNow
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 Iwaki

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.

Iwaki experiences extreme seasonal variation in the perceived humidity.

The muggier period of the year lasts for 3.3 months, from June 16 to September 26, during which time the comfort level is muggy, oppressive, or miserable at least 22% of the time. The month with the most muggy days in Iwaki is August, with 26.6 days that are muggy or worse.

The least muggy day of the year is February 14, when muggy conditions are essentially unheard of.

Humidity Comfort Levels in Iwaki

Humidity Comfort Levels in IwakimuggyJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Feb 140%Feb 140%90%Aug 790%Aug 7Jun 1622%Jun 1622%Sep 2622%Sep 2622%NowNowoppressiveoppressivedrydrymuggymuggymiserablemiserablecomfortablecomfortable
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 0.0d0.0d0.0d0.0d0.6d7.2d22.1d26.6d13.4d1.5d0.0d0.0d

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

The windier part of the year lasts for 6.2 months, from October 29 to May 2, with average wind speeds of more than 7.9 miles per hour. The windiest month of the year in Iwaki is February, with an average hourly wind speed of 10.2 miles per hour.

The calmer time of year lasts for 5.8 months, from May 2 to October 29. The calmest month of the year in Iwaki is July, with an average hourly wind speed of 5.7 miles per hour.

Average Wind Speed in Iwaki

Average Wind Speed in IwakiwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph2 mph2 mph4 mph4 mph6 mph6 mph8 mph8 mph10 mph10 mph12 mph12 mph14 mph14 mph16 mph16 mphFeb 610.3 mphFeb 610.3 mphJul 185.6 mphJul 185.6 mphOct 297.9 mphOct 297.9 mphMay 27.9 mphMay 27.9 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) 10.110.29.68.67.26.15.76.17.17.78.49.5

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

The wind is most often from the north for 2.3 months, from February 1 to April 10 and for 2.7 months, from September 13 to December 5, with a peak percentage of 44% on February 24. The wind is most often from the south for 5.1 months, from April 10 to September 13, with a peak percentage of 48% on August 7. The wind is most often from the west for 1.9 months, from December 5 to February 1, with a peak percentage of 46% on January 1.

Wind Direction in Iwaki

Wind Direction in IwakiWNSNWJanFebMarAprMayJunJulAugSepOctNovDec0%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).

Iwaki 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 significant seasonal variation over the course of the year.

The time of year with warmer water lasts for 2.6 months, from July 17 to October 3, with an average temperature above 70°F. The month of the year in Iwaki with the warmest water is August, with an average temperature of 74°F.

The time of year with cooler water lasts for 3.4 months, from January 8 to April 22, with an average temperature below 57°F. The month of the year in Iwaki with the coolest water is March, with an average temperature of 53°F.

Average Water Temperature in Iwaki

Average Water Temperature in IwakiwarmcoolJanFebMarAprMayJunJulAugSepOctNovDec45°F45°F50°F50°F55°F55°F60°F60°F65°F65°F70°F70°F75°F75°F80°F80°FAug 2275°FAug 2275°F52°FMar 152°FMar 1Jul 1770°FJul 1770°FOct 370°FOct 370°FJan 857°FJan 857°FApr 2257°FApr 2257°FNowNow
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 56°F53°F53°F56°F60°F65°F70°F74°F73°F68°F64°F60°F

To characterize how pleasant the weather is in Iwaki 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 Iwaki for general outdoor tourist activities is from mid July to late September, with a peak score in the second week of August.

Tourism Score in Iwaki

Tourism Score in Iwakibest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.56.50.00.0NowNowtemperaturetemperature 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 Iwaki for hot-weather activities is from late July to late August, with a peak score in the second week of August.

Beach/Pool Score in Iwaki

Beach/Pool Score in IwakiJanFebMarAprMayJunJulAugSepOctNovDec002244668810105.85.80.00.0NowNowtemperaturetemperature 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 Iwaki typically lasts for 8.0 months (247 days), from around March 28 to around November 30, rarely starting before March 10 or after April 14, and rarely ending before November 12 or after December 17.

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

Time Spent in Various Temperature Bands and the Growing Season in Iwakigrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%50%Mar 2850%Mar 2850%Nov 3050%Nov 3090%Apr 1490%Apr 1490%Nov 1290%Nov 1210%Mar 1010%Mar 1010%Dec 1710%Dec 17Jul 24100%Jul 24100%freezingvery coldcoldcoolcomfortablewarmhot
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 Iwaki should appear around April 17, only rarely appearing before April 7 or after April 27.

Growing Degree Days in Iwaki

Growing Degree Days in IwakiJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F500°F500°F1,000°F1,000°F1,500°F1,500°F2,000°F2,000°F2,500°F2,500°F3,000°F3,000°F3,500°F3,500°FApr 1788°FApr 1788°FJun 27900°FJun 27900°FAug 61,800°FAug 61,800°FDec 313,465°FDec 313,465°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 significant seasonal variation over the course of the year.

The brighter period of the year lasts for 4.5 months, from April 12 to August 26, with an average daily incident shortwave energy per square meter above 5.2 kWh. The brightest month of the year in Iwaki is May, with an average of 5.8 kWh.

The darker period of the year lasts for 3.1 months, from November 5 to February 8, with an average daily incident shortwave energy per square meter below 3.0 kWh. The darkest month of the year in Iwaki is December, with an average of 2.3 kWh.

Average Daily Incident Shortwave Solar Energy in Iwaki

Average Daily Incident Shortwave Solar Energy in IwakibrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWhJun 15.9 kWhJun 15.9 kWhDec 222.3 kWhDec 222.3 kWhApr 125.2 kWhApr 125.2 kWhAug 265.2 kWhAug 265.2 kWhNov 53.0 kWhNov 53.0 kWhFeb 83.0 kWhFeb 83.0 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) 2.53.24.25.35.85.65.65.54.43.52.72.3

For the purposes of this report, the geographical coordinates of Iwaki are 37.050 deg latitude, 140.883 deg longitude, and 30 ft elevation.

The topography within 2 miles of Iwaki contains only modest variations in elevation, with a maximum elevation change of 374 feet and an average elevation above sea level of 111 feet. Within 10 miles contains only modest variations in elevation (2,579 feet). Within 50 miles contains large variations in elevation (5,505 feet).

The area within 2 miles of Iwaki is covered by cropland (58%) and trees (36%), within 10 miles by trees (49%) and water (30%), and within 50 miles by water (60%) and trees (29%).

This report illustrates the typical weather in Iwaki, 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 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Iwaki.

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

The stations contributing to this reconstruction are:

  • Hyakuri Ab (RJAH, 45%, 65 mi, southwest, 75 ft elevation change)
  • Sendai Airport (RJSS, 36%, 75 mi, north, -16 ft elevation change)
  • Niigata Airport (RJSN, 19%, 115 mi, northwest, -16 ft elevation change)

To get a sense of how much these sources agree with each other, you can view a comparison of Iwaki 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.