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Average Weather at Juan Santamaría International Airport Costa Rica

At Juan Santamaría International Airport, the wet season is muggy and overcast, the dry season is partly cloudy, and it is warm year round. Over the course of the year, the temperature typically varies from 66°F to 85°F and is rarely below 63°F or above 88°F.

Climate Summary

warmhotwarmJanFebMarAprMayJunJulAugSepOctNovDec64%64%5%5%overcastclearprecipitation: 6.5 inprecipitation: 6.5 in0.5 in0.5 inmuggy: 70%muggy: 70%4%4%drydrytourism score: 7.5tourism score: 7.54.34.3
Click on each chart for more information.

Based on the tourism score, the best time of year to visit Juan Santamaría International Airport for warm-weather activities is from mid December to mid March.

Temperature

The temperature at Juan Santamaría International Airport varies so little throughout the year that it is not entirely meaningful to discuss hot and cold seasons.

Average High and Low Temperature

Average High and Low Temperature at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec0°F10°F20°F30°F40°F50°F60°F70°F80°F90°F100°FSep 2980°FSep 2980°FApr 285°FApr 285°F66°F66°F67°F67°FMar 584°FMar 584°FApr 2984°FApr 2984°FDec 981°FDec 981°F66°F66°F68°F68°F66°F66°FLowHigh
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.

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

Average Hourly Temperature at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec12 AM4 AM8 AM12 PM4 PM8 PM12 AMwarmcomfortablecomfortable
The average hourly temperature, color coded into bands: 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 shaded overlays indicate night and civil twilight.

Evinayong, Equatorial Guinea (6,532 miles away) and Bangahan, Philippines (10,108 miles) are the far-away foreign places with temperatures most similar to Juan Santamaría International Airport (view comparison).

Clouds

At Juan Santamaría International Airport, the average percentage of the sky covered by clouds experiences extreme seasonal variation over the course of the year.

The clearer part of the year at Juan Santamaría International Airport begins around November 24 and lasts for 4.5 months, ending around April 9. On January 1, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 64% of the time, and overcast or mostly cloudy 36% of the time.

The cloudier part of the year begins around April 9 and lasts for 7.5 months, ending around November 24. On June 5, the cloudiest day of the year, the sky is overcast or mostly cloudy 95% of the time, and clear, mostly clear, or partly cloudy 5% of the time.

Cloud Cover Categories

Cloud Cover Categories at Juan Santamaría International AirportclearerclearercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jan 164%Jan 164%Jun 55%Jun 55%Nov 2434%Nov 2434%Apr 936%Apr 936%clearmostly cloudyovercastmostly clearpartly cloudy
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds: clear < 20% < mostly clear < 40% < partly cloudy < 60% < mostly cloudy < 80% < overcast.

Precipitation

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

The wetter season lasts 6.7 months, from May 4 to November 26, with a greater than 28% chance of a given day being a wet day. The chance of a wet day peaks at 51% on October 7.

The drier season lasts 5.3 months, from November 26 to May 4. The smallest chance of a wet day is 5% on March 13.

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 throughout the year is rain alone, with a peak probability of 51% on October 7.

Daily Chance of Precipitation

Daily Chance of Precipitation at Juan Santamaría International AirportwetdrydryJanFebMarAprMayJunJulAugSepOctNovDec0%10%20%30%40%50%60%70%80%90%100%Oct 751%Oct 751%Mar 135%Mar 135%Jan 111%Jan 111%May 428%May 428%Nov 2628%Nov 2628%rain
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).

Rainfall

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. Juan Santamaría International Airport experiences extreme seasonal variation in monthly rainfall.

Rain falls throughout the year at Juan Santamaría International Airport. The most rain falls during the 31 days centered around October 11, with an average total accumulation of 6.5 inches.

The least rain falls around March 15, with an average total accumulation of 0.5 inches.

Average Monthly Rainfall

Average Monthly Rainfall at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec0 in2 in4 in6 in8 in10 in12 in14 inOct 116.5 inOct 116.5 inMar 150.5 inMar 150.5 inJun 45.6 inJun 45.6 inJul 224.2 inJul 224.2 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 liquid-equivalent snowfall.

Sun

The length of the day at Juan Santamaría International Airport does not vary substantially over the course of the year, staying within 42 minutes of 12 hours throughout. In 2017, the shortest day is December 21, with 11 hours, 33 minutes of daylight; the longest day is June 20, with 12 hours, 43 minutes of daylight.

Hours of Daylight and Twilight

Hours of Daylight and Twilight at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 6 minMar 2012 hr, 6 minMar 2012 hr, 43 minJun 2012 hr, 43 minJun 2012 hr, 7 minSep 2212 hr, 7 minSep 2211 hr, 33 minDec 2111 hr, 33 minDec 21nightnightday
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.

The earliest sunrise is at 5:14 AM on May 29, and the latest sunrise is 45 minutes later at 5:59 AM on January 27. The earliest sunset is at 5:11 PM on November 16, and the latest sunset is 51 minutes later at 6:02 PM on July 11.

Daylight saving time (DST) is not observed at Juan Santamaría International Airport during 2017.

Sunrise & Sunset with Twilight

Sunrise & Sunset with Twilight at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PMMay 295:14 AMMay 295:14 AM6:02 PMJul 116:02 PMJul 11Nov 165:11 PMNov 165:11 PM5:59 AMJan 275:59 AMJan 27daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunriseSunset
The solar day over the course of the year 2017. 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.

Humidity

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.

Juan Santamaría International Airport experiences extreme seasonal variation in the perceived humidity.

The muggier period of the year lasts for 7.9 months, from April 15 to December 10, during which time the comfort level is muggy, oppressive, or miserable at least 20% of the time. The muggiest day of the year is June 4, with muggy conditions 70% of the time.

The least muggy day of the year is February 2, with muggy conditions 4% of the time.

Humidity Comfort Levels

Humidity Comfort Levels at Juan Santamaría International AirportmuggyJanFebMarAprMayJunJulAugSepOctNovDec0%10%20%30%40%50%60%70%80%90%100%Feb 24%Feb 24%Jun 470%Jun 470%Apr 1520%Apr 1520%Dec 1020%Dec 1020%humidhumiddrydrymuggymuggycomfortablecomfortableoppressiveoppressive
The percentage of time spent at various humidity comfort levels, categorized by dew point: dry < 55°F < comfortable < 60°F < humid < 65°F < muggy < 70°F < oppressive < 75°F < miserable.

Wind

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 Juan Santamaría International Airport experiences mild seasonal variation over the course of the year.

The windier part of the year lasts for 4.2 months, from December 7 to April 12, with average wind speeds of more than 3.1 miles per hour. The windiest day of the year is February 5, with an average hourly wind speed of 4.1 miles per hour.

The calmer time of year lasts for 7.8 months, from April 12 to December 7. The calmest day of the year is September 11, with an average hourly wind speed of 2.0 miles per hour.

Average Wind Speed

Average Wind Speed at Juan Santamaría International AirportwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph1 mph2 mph3 mph4 mph5 mph6 mphFeb 54.1 mphFeb 54.1 mphSep 112.0 mphSep 112.0 mphDec 73.1 mphDec 73.1 mphApr 123.1 mphApr 123.1 mph
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.

The predominant average hourly wind direction at Juan Santamaría International Airport varies throughout the year.

The wind is most often from the west for 1.3 months, from September 13 to October 21, with a peak percentage of 37% on September 30. The wind is most often from the east for 11 months, from October 21 to September 13, with a peak percentage of 63% on January 1.

Wind Direction

Wind Direction at Juan Santamaría International AirportEWEJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%eastwestnorthsouth
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions (north, east, south, and west), excluding hours in which the mean wind speed is less than 1 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Water Temperature

Juan Santamaría International Airport 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 does not vary significantly over the course of the year, remaining within 1°F of 83°F throughout.

Average Water Temperature

The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.

Best Time of Year to Visit

To characterize how pleasant the weather is at Juan Santamaría International 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 Juan Santamaría International Airport for general outdoor tourist activities is from mid December to mid March, with a peak score in the first week of January.

Tourism Score

Tourism Score at Juan Santamaría International Airportbest timeJanFebMarAprMayJunJulAugSepOctNovDec02468107.57.54.34.34.44.4 precipitationprecipitationcloudscloudstemperaturetemperaturetourism 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 Juan Santamaría International Airport for hot-weather activities is from early December to early April, with a peak score in the first week of January.

Beach/Pool Score

Beach/Pool Score at Juan Santamaría International Airportbest timeJanFebMarAprMayJunJulAugSepOctNovDec02468106.16.13.53.54.34.33.83.8 precipitationprecipitationcloudscloudstemperaturetemperaturebeach/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.

Growing Season

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).

Temperatures at Juan Santamaría International Airport are sufficiently warm year round that it is not entirely meaningful to discuss the growing season in these terms. We nevertheless include the chart below as an illustration of the distribution of temperatures experienced throughout the year.

Time Spent in Various Temperature Bands and the Growing Season

Time Spent in Various Temperature Bands and the Growing Season at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%100%Jan 1100%Jan 1100%Jul 3100%Jul 3warmhotcomfortablecool
The percentage of time spent in various temperature bands: 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 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

Growing Degree Days at Juan Santamaría International AirportJanFebMarAprMayJunJulAugSepOctNovDec0°F1,000°F2,000°F3,000°F4,000°F5,000°F6,000°F7,000°F8,000°FJan 590°FJan 590°FMar 201,800°FMar 201,800°FDec 318,222°FDec 318,222°F
The average growing degree days accumulated over the course of the year, with 25th to 75th and 10th to 90th percentile bands.

Solar Energy

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 2.4 months, from February 2 to April 14, with an average daily incident shortwave energy per square meter above 6.2 kWh. The brightest day of the year is March 21, with an average of 6.9 kWh.

The darker period of the year lasts for 5.9 months, from May 20 to November 16, with an average daily incident shortwave energy per square meter below 4.4 kWh. The darkest day of the year is October 11, with an average of 3.8 kWh.

Average Daily Incident Shortwave Solar Energy

Average Daily Incident Shortwave Solar Energy at Juan Santamaría International AirportbrightdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh1 kWh2 kWh3 kWh4 kWh5 kWh6 kWh7 kWh8 kWhMar 216.9 kWhMar 216.9 kWhOct 113.8 kWhOct 113.8 kWhFeb 26.2 kWhFeb 26.2 kWhMay 204.4 kWhMay 204.4 kWhNov 164.4 kWhNov 164.4 kWh
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.

Topography

For the purposes of this report, the geographical coordinates of Juan Santamaría International Airport are 9.994 deg latitude, -84.209 deg longitude, and 2,956 ft elevation.

The topography within 2 miles of Juan Santamaría International Airport contains significant variations in elevation, with a maximum elevation change of 495 feet and an average elevation above sea level of 2,957 feet. Within 10 miles contains significant variations in elevation (6,430 feet). Within 50 miles also contains extreme variations in elevation (11,447 feet).

The area within 2 miles of Juan Santamaría International Airport is covered by grassland (71%) and trees (15%), within 10 miles by grassland (48%) and trees (35%), and within 50 miles by trees (50%) and grassland (17%).

Data Sources

This report illustrates the typical weather at Juan Santamaría International 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

Juan Santamaría International 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.

There are no other weather stations in our network within 200 kilometers of this location. Consequently, in the case of missing or erroneous measurements from this station, we fall back on NASA's MERRA-2 modern-era reanalysis , adjusted according to typical seasonal and diurnal differences between this station and the wide-area MERRA-2 reconstructed values.

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , 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 aiports and weather stations are provided by AskGeo.com .

Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.

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.