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Average Weather in January in Aserrí Costa Rica

In Aserrí, the month of January is characterized by essentially constant daily high temperatures, with daily highs around 74°F throughout the month, rarely exceeding 78°F or dropping below 71°F.

Daily low temperatures are around 61°F, rarely falling below 57°F or exceeding 64°F. The lowest daily average low temperature is 60°F on January 23.

For reference, on April 2, the hottest day of the year, temperatures in Aserrí typically range from 61°F to 77°F, while on October 2, the coldest day of the year, they range from 60°F to 73°F.

Average High and Low Temperature in January

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 hourly average temperatures for the quarter of the year centered on January. The horizontal axis is the day, 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 January

Average Hourly Temperature in January in Aserrí12 AM4 AM8 AM12 PM4 PM8 PM12 AM181522291122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292930303131DecFebcoolcomfortablewarm
The average hourly temperature, color coded into bands: frigid < 15°F < freezing < 32°F < chilly < 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.

Clouds

The month of January in Aserrí experiences gradually increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 36% to 41%. The lowest chance of overcast or mostly cloudy conditions is 36% on January 2.

The clearest day of the month is January 2, with clear, mostly clear, or partly cloudy conditions 64% of the time.

For reference, on June 5, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 96%, while on January 2, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 64%.

Cloud Cover in January

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. In Aserrí, the chance of a wet day over the course of January is gradually decreasing, starting the month at 13% and ending it at 9%.

For reference, the year's highest daily chance of a wet day is 52% on October 7, and its lowest chance is 7% on March 16.

Probability of Precipitation in January

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 month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.

The average sliding 31-day rainfall during January in Aserrí is decreasing, starting the month at 1.4 inches, when it rarely exceeds 3.3 inches or falls below 0.1 inches, and ending the month at 0.8 inches, when it rarely exceeds 2.2 inches.

Average Monthly Rainfall in January

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

Over the course of January in Aserrí, the length of the day is essentially constant. The shortest day of the month is January 1, with 11 hours, 34 minutes of daylight and the longest day is January 31, with 11 hours, 43 minutes of daylight.

Hours of Daylight and Twilight in January

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 of the month in Aserrí is 5:53 AM on January 1 and the latest sunrise is 6 minutes later at 5:58 AM on January 27.

The earliest sunset is 5:27 PM on January 1 and the latest sunset is 14 minutes later at 5:41 PM on January 31.

Daylight saving time is not observed in Aserrí during 2017.

For reference, on June 21, the longest day of the year, the Sun rises at 5:17 AM and sets 12 hours, 42 minutes later, at 5:59 PM, while on December 21, the shortest day of the year, it rises at 5:48 AM and sets 11 hours, 33 minutes later, at 5:21 PM.

Sunrise & Sunset with Twilight in January

The solar day over the course of January. 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.

The chance that a given day will be muggy in Aserrí is essentially constant during January, remaining within 1% of 3% throughout.

The lowest chance of a muggy day during January is 2% on January 24.

For reference, on June 2, the muggiest day of the year, there are muggy conditions 46% of the time, while on January 24, the least muggy day of the year, there are muggy conditions 2% of the time.

Humidity Comfort Levels in January

Humidity Comfort Levels in January in Aserrí0%10%20%30%40%50%60%70%80%90%100%181522291122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292930303131DecFebJan 242%Jan 242%Jan 14%Jan 14%Jan 312%Jan 312%Jan 113%Jan 113%muggymuggyhumidhumidcomfortablecomfortabledrydryoppressiveoppressive
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 in Aserrí is essentially constant during January, remaining within 0.1 miles per hour of 1.5 miles per hour throughout.

For reference, on February 24, the windiest day of the year, the daily average wind speed is 1.6 miles per hour, while on July 23, the calmest day of the year, the daily average wind speed is 1.0 miles per hour.

Average Wind Speed in January

The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
The hourly average wind direction in Aserrí throughout January is predominantly from the east, with a peak proportion of 67% on January 20.

Wind Direction in January

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

Aserrí 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 surface water temperature in Aserrí is essentially constant during January, remaining around 83°F throughout.

Average Water Temperature in January

The daily average water temperature (purple line), 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 in Aserrí is gradually increasing during January, rising by 0.7 kWh, from 5.5 kWh to 6.2 kWh, over the course of the month.

Average Daily Incident Shortwave Solar Energy in January

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 Aserrí are 9.859 deg latitude, -84.092 deg longitude, and 4,751 ft elevation.

The topography within 2 miles of Aserrí contains large variations in elevation, with a maximum elevation change of 2,589 feet and an average elevation above sea level of 4,736 feet. Within 10 miles contains large variations in elevation (6,447 feet). Within 50 miles also contains extreme variations in elevation (12,490 feet).

The area within 2 miles of Aserrí is covered by trees (45%) and grassland (42%), within 10 miles by trees (45%) and grassland (38%), and within 50 miles by trees (48%) and water (20%).

Data Sources

This report illustrates the typical weather in Aserrí year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.

Temperature and Dew Point

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

At a distance of 20 kilometers from Aserrí, closer than our threshold of 150 kilometers, this station is deemed sufficiently nearby to be relied upon as our primary source for temperature and dew point records.

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

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

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical 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.