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Average Weather in Bissorã Guinea-Bissau

In Bissorã, the wet season is oppressive and overcast, the dry season is humid and partly cloudy, and it is hot year round. Over the course of the year, the temperature typically varies from 63°F to 98°F and is rarely below 59°F or above 103°F.

Based on the beach/pool score, the best time of year to visit Bissorã for hot-weather activities is from late November to mid April.

Climate Summary

hotswelteringhotJanFebMarAprMayJunJulAugSepOctNovDecNowNow62%62%18%18%overcastclearprecipitation: 15.3 inprecipitation: 15.3 in0.0 in0.0 inmuggy: 100%muggy: 100%2%2%drydrybeach/pool score: 7.2beach/pool score: 7.23.13.1
Click on each chart for more information.

Temperature

The hot season lasts for 3.2 months, from February 18 to May 25, with an average daily high temperature above 96°F. The hottest day of the year is March 31, with an average high of 98°F and low of 71°F.

The cool season lasts for 2.5 months, from July 9 to September 24, with an average daily high temperature below 88°F. The coldest day of the year is January 6, with an average low of 63°F and high of 90°F.

Average High and Low Temperature

Average High and Low Temperature in BissorãhotcoolJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°F110°F110°FJan 690°FJan 690°FMar 3198°FMar 3198°F63°F63°F71°F71°FFeb 1896°FFeb 1896°FMay 2596°FMay 2596°FJul 988°FJul 988°FSep 2488°FSep 2488°F67°F67°F76°F76°F76°F76°F75°F75°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.

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 in BissorãJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM4 AM4 AM8 AM8 AM12 PM12 PM4 PM4 PM8 PM8 PM12 AM12 AMNowNowcoolcomfortablecomfortablewarmwarmhotswelteringcool
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.

Dombivli, India (5,855 miles away) is the far-away foreign place with temperatures most similar to Bissorã (view comparison).

Clouds

In Bissorã, 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 Bissorã begins around November 13 and lasts for 6.9 months, ending around June 10. On March 2, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 62% of the time, and overcast or mostly cloudy 38% of the time.

The cloudier part of the year begins around June 10 and lasts for 5.1 months, ending around November 13. On September 11, the cloudiest day of the year, the sky is overcast or mostly cloudy 82% of the time, and clear, mostly clear, or partly cloudy 18% of the time.

Cloud Cover Categories

Cloud Cover Categories in BissorãclearerclearercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Mar 262%Mar 262%Sep 1118%Sep 1118%Nov 1340%Nov 1340%Jun 1040%Jun 1040%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.

Precipitation

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

The wetter season lasts 4.0 months, from June 14 to October 13, 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 19.

The drier season lasts 8.0 months, from October 13 to June 14. The smallest chance of a wet day is 0% on December 9.

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 19.

Daily Chance of Precipitation

Daily Chance of Precipitation in BissorãwetdrydryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Aug 1992%Aug 1992%Dec 90%Dec 90%Jun 1446%Jun 1446%Oct 1346%Oct 1346%NowNowrain
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. Bissorã experiences extreme seasonal variation in monthly rainfall.

The rainy period of the year lasts for 6.0 months, from May 11 to November 11, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around August 18, with an average total accumulation of 15.3 inches.

The rainless period of the year lasts for 6.0 months, from November 11 to May 11. The least rain falls around March 9, with an average total accumulation of 0.0 inches.

Average Monthly Rainfall

Average Monthly Rainfall in BissorãrainJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in5 in5 in10 in10 in15 in15 in20 in20 in25 in25 inAug 1815.3 inAug 1815.3 inMar 90.0 inMar 90.0 inJan 110.0 inJan 110.0 inDec 130.0 inDec 130.0 inMay 110.5 inMay 110.5 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 liquid-equivalent snowfall.

Sun

The length of the day in Bissorã does not vary substantially over the course of the year, staying within 50 minutes of 12 hours throughout. In 2021, the shortest day is December 21, with 11 hours, 25 minutes of daylight; the longest day is June 21, with 12 hours, 51 minutes of daylight.

Hours of Daylight and Twilight

Hours of Daylight and Twilight in BissorãJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 6 minMar 2012 hr, 6 minMar 2012 hr, 51 minJun 2112 hr, 51 minJun 2112 hr, 7 minSep 2212 hr, 7 minSep 2211 hr, 25 minDec 2111 hr, 25 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.

The earliest sunrise is at 6:35 AM on May 31, and the latest sunrise is 52 minutes later at 7:27 AM on January 24. The earliest sunset is at 6:33 PM on November 18, and the latest sunset is 58 minutes later at 7:31 PM on July 10.

Daylight saving time (DST) is not observed in Bissorã during 2021.

Sunrise & Sunset with Twilight

Sunrise & Sunset with Twilight in BissorãJanFebMarAprMayJunJulAugSepOctNovDec2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMMay 316:35 AMMay 316:35 AM7:31 PMJul 107:31 PMJul 10Nov 186:33 PMNov 186:33 PM7:27 AMJan 247:27 AMJan 24daynightnightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
The solar day over the course of the year 2021. 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.

Moon

The figure below presents a compact representation of key lunar data for 2021. 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

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.

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.

Bissorã experiences extreme seasonal variation in the perceived humidity.

The muggier period of the year lasts for 8.5 months, from March 25 to December 9, during which time the comfort level is muggy, oppressive, or miserable at least 27% of the time. The muggiest day of the year is August 25, with muggy conditions 100% of the time.

The least muggy day of the year is January 9, with muggy conditions 2% of the time.

Humidity Comfort Levels

Humidity Comfort Levels in BissorãmuggyJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jan 92%Jan 92%100%Aug 25100%Aug 25Mar 2527%Mar 2527%Dec 927%Dec 927%NowNowmiserablemiserableoppressiveoppressivemuggymuggydrydryhumidhumidcomfortablecomfortable
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.

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

The windier part of the year lasts for 9.0 months, from December 5 to September 3, with average wind speeds of more than 6.1 miles per hour. The windiest day of the year is May 21, with an average hourly wind speed of 7.7 miles per hour.

The calmer time of year lasts for 3.0 months, from September 3 to December 5. The calmest day of the year is October 21, with an average hourly wind speed of 4.4 miles per hour.

Average Wind Speed

Average Wind Speed in BissorãwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph1 mph1 mph2 mph2 mph3 mph3 mph4 mph4 mph5 mph5 mph6 mph6 mph7 mph7 mph8 mph8 mph9 mph9 mph10 mph10 mph11 mph11 mphMay 217.7 mphMay 217.7 mphOct 214.4 mphOct 214.4 mphDec 56.1 mphDec 56.1 mphSep 36.1 mphSep 36.1 mphNowNow
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 Bissorã varies throughout the year.

The wind is most often from the west for 7.2 months, from March 24 to November 1, with a peak percentage of 71% on July 10. The wind is most often from the north for 4.7 months, from November 1 to March 24, with a peak percentage of 59% on January 1.

Wind Direction

Wind Direction in BissorãNWNJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwestnorthsoutheast
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).

Water Temperature

Bissorã 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 some seasonal variation over the course of the year.

The time of year with warmer water lasts for 2.1 months, from September 25 to November 29, with an average temperature above 83°F. The day of the year with the warmest water is November 3, with an average temperature of 85°F.

The time of year with cooler water lasts for 2.7 months, from January 1 to March 24, with an average temperature below 78°F. The day of the year with the coolest water is January 23, with an average temperature of 76°F.

Average Water Temperature

Average Water Temperature in BissorãwarmcoolJanFebMarAprMayJunJulAugSepOctNovDec72°F72°F74°F74°F76°F76°F78°F78°F80°F80°F82°F82°F84°F84°F86°F86°F88°F88°FNov 385°FNov 385°F76°FJan 2376°FJan 23Sep 2583°FSep 2583°FJan 178°FJan 178°FMar 2478°FMar 2478°FNowNow
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 in Bissorã 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 Bissorã for general outdoor tourist activities is from mid December to mid February, with a peak score in the second week of January.

Tourism Score

Tourism Score in BissorãJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.36.32.02.0NowNowprecipitationprecipitationcloudscloudstemperaturetemperature tourism 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 Bissorã for hot-weather activities is from late November to mid April, with a peak score in the last week of February.

Beach/Pool Score

Beach/Pool Score in Bissorãbest timebest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810107.27.23.13.16.86.8NowNowprecipitationprecipitationcloudscloudstemperaturetemperature beach/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 in Bissorã 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 in BissorãJanFebMarAprMayJunJulAugSepOctNovDec0%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 3NowNowcoolcomfortablewarmhotsweltering
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.

Growing Degree Days

Growing Degree Days in BissorãJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F2,000°F2,000°F4,000°F4,000°F6,000°F6,000°F8,000°F8,000°F10,000°F10,000°FJan 590°FJan 590°FMar 101,800°FMar 101,800°FDec 3110,678°FDec 3110,678°FNowNow
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 some seasonal variation over the course of the year.

The brighter period of the year lasts for 2.7 months, from February 28 to May 17, with an average daily incident shortwave energy per square meter above 6.4 kWh. The brightest day of the year is April 10, with an average of 7.0 kWh.

The darker period of the year lasts for 4.4 months, from June 25 to November 6, with an average daily incident shortwave energy per square meter below 4.7 kWh. The darkest day of the year is August 24, with an average of 4.2 kWh.

Average Daily Incident Shortwave Solar Energy

Average Daily Incident Shortwave Solar Energy in BissorãbrightdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWhApr 107.0 kWhApr 107.0 kWhAug 244.2 kWhAug 244.2 kWhFeb 286.4 kWhFeb 286.4 kWhMay 176.4 kWhMay 176.4 kWhJun 254.7 kWhJun 254.7 kWhNov 64.7 kWhNov 64.7 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.

Topography

For the purposes of this report, the geographical coordinates of Bissorã are 12.223 deg latitude, -15.448 deg longitude, and 85 ft elevation.

The topography within 2 miles of Bissorã contains only modest variations in elevation, with a maximum elevation change of 151 feet and an average elevation above sea level of 70 feet. Within 10 miles also contains only modest variations in elevation (223 feet). Within 50 miles also contains only modest variations in elevation (322 feet).

The area within 2 miles of Bissorã is covered by cropland (38%), shrubs (21%), grassland (21%), and trees (18%), within 10 miles by cropland (33%) and trees (23%), and within 50 miles by trees (30%) and cropland (23%).

Data Sources

This report illustrates the typical weather in Bissorã, 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 Bissorã.

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

The stations contributing to this reconstruction are: Bissau Airport (62%, 43 kilometers, southwest); Kolda North Airport (20%, 90 kilometers, northeast); and Ziguinchor Airport (18%, 98 kilometers, west).

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 © 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.