Average Weather in Coyah Guinea

In Coyah, the wet season is warm, oppressive, and overcast and the dry season is hot, muggy, and partly cloudy. Over the course of the year, the temperature typically varies from 71°F to 97°F and is rarely below 67°F or above 100°F.

The hot season lasts for 3.4 months, from January 18 to April 30, with an average daily high temperature above 94°F. The hottest day of the year is March 2, with an average high of 97°F and low of 75°F.

The cool season lasts for 4.1 months, from June 22 to October 25, with an average daily high temperature below 84°F. The coldest day of the year is January 1, with an average low of 71°F and high of 91°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

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

In Coyah, 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 Coyah begins around November 16 and lasts for 5.3 months, ending around April 24. On February 3, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 63% of the time, and overcast or mostly cloudy 37% of the time.

The cloudier part of the year begins around April 24 and lasts for 6.7 months, ending around November 16. On August 17, the cloudiest day of the year, the sky is overcast or mostly cloudy 84% of the time, and clear, mostly clear, or partly cloudy 16% of the time.

Cloud Cover

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 in Coyah varies very significantly throughout the year.

The wetter season lasts 5.0 months, from May 21 to October 20, with a greater than 46% chance of a given day being a wet day. The chance of a wet day peaks at 92% on August 23.

The drier season lasts 7.0 months, from October 20 to May 21. The smallest chance of a wet day is 0% on January 4.

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 92% on August 23.

Daily Chance of Precipitation

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. Coyah experiences extreme seasonal variation in monthly rainfall.

The rainy period of the year lasts for 7.7 months, from April 7 to November 29, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around August 7, with an average total accumulation of 29.9 inches.

The rainless period of the year lasts for 4.3 months, from November 29 to April 7. The least rain falls around January 9, with an average total accumulation of 0.0 inches.

Average Monthly Rainfall

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 in Coyah does not vary substantially over the course of the year, staying within 41 minutes of 12 hours throughout. In 2017, the shortest day is December 21, with 11 hours, 34 minutes of daylight; the longest day is June 21, with 12 hours, 42 minutes of daylight.

Hours of Daylight and Twilight

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 6:31 AM on May 28, and the latest sunrise is 44 minutes later at 7:15 AM on January 27. The earliest sunset is at 6:28 PM on November 16, and the latest sunset is 50 minutes later at 7:18 PM on July 13.

Daylight saving time (DST) is not observed in Coyah during 2017.

Sunrise & Sunset with Twilight

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.

Coyah experiences extreme seasonal variation in the perceived humidity.

The muggier period of the year lasts for 9.8 months, from February 23 to December 17, during which time the comfort level is muggy, oppressive, or miserable at least 54% of the time. The muggiest day of the year is August 19, with muggy conditions 100% of the time.

The least muggy day of the year is January 12, with muggy conditions 38% of the time.

Humidity Comfort Levels

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 Coyah experiences mild seasonal variation over the course of the year.

The windier part of the year lasts for 2.9 months, from June 23 to September 19, with average wind speeds of more than 3.5 miles per hour. The windiest day of the year is August 8, with an average hourly wind speed of 5.0 miles per hour.

The calmer time of year lasts for 9.1 months, from September 19 to June 23. The calmest day of the year is November 13, with an average hourly wind speed of 2.2 miles per hour.

Average Wind Speed

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 in Coyah varies throughout the year.

The wind is most often from the west for 10 months, from January 11 to November 26, with a peak percentage of 85% on April 14. The wind is most often from the east for 1.5 months, from November 26 to January 11, with a peak percentage of 34% on January 1.

Wind Direction

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

Coyah 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 2°F of 82°F throughout.

Average Water Temperature

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 experiences some seasonal variation over the course of the year.

The brighter period of the year lasts for 2.6 months, from February 5 to April 24, with an average daily incident shortwave energy per square meter above 5.8 kWh. The brightest day of the year is March 21, with an average of 6.4 kWh.

The darker period of the year lasts for 5.5 months, from May 29 to November 14, with an average daily incident shortwave energy per square meter below 4.4 kWh. The darkest day of the year is October 19, with an average of 3.9 kWh.

Average Daily Incident Shortwave Solar Energy

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 Coyah are 9.706 deg latitude, -13.385 deg longitude, and 95 ft elevation.

The topography within 2 miles of Coyah contains very significant variations in elevation, with a maximum elevation change of 1,549 feet and an average elevation above sea level of 274 feet. Within 10 miles contains very significant variations in elevation (3,268 feet). Within 50 miles contains large variations in elevation (3,976 feet).

The area within 2 miles of Coyah is covered by trees (33%), cropland (32%), and artificial surfaces (25%), within 10 miles by trees (33%) and cropland (32%), and within 50 miles by water (31%) and trees (27%).

Data Sources

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

Coyah is further than 200 kilometers from the nearest reliable weather station, so the weather-related data on this page were taken entirely from NASA's MERRA-2 satellite-era reanalysis . 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.

The temperature and dew point estimates are corrected for the difference between the reference elevation of the MERRA-2 grid cell and the elevation of Coyah, according to the International Standard Atmosphere .

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.

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.