Last updated: January 18, 2025
Bissau, the capital of Guinea-Bissau, experiences a tropical savanna climate classified under the Köppen-Geiger system as Aw. This region showcases significant temperature variation throughout the year, with minimum temperatures dipping to 17°C (64°F) in January and soaring to a blistering 41°C (106°F) in April. The average annual temperature remains remarkably warm at around 28°C (82°F), demonstrating the region's distinct seasonal changes and highlighting the need for adaptive strategies in response to increasing temperatures.
Bissau, Guinea-Bissau experiences distinct seasonal temperature patterns, characterized by warming trends leading into the dry season. January marks the onset of cooler temperatures, with minimums around 17°C (64°F) and maximums peaking at 38°C (100°F). As the months progress toward April, temperatures rise steadily, with April recording the highest maximum of 41°C (106°F) alongside average temperatures of 29°C (84°F). The onset of the rainy season in June brings a slight moderation in temperatures, with maximums dropping to the lower 30s°C and averages remaining steady. By August, the city experiences its coolest period, with maximum temperatures around 32°C (90°F), before gradually warming again in the latter months. Throughout the year, minimum temperatures fluctuate only slightly, fostering a generally warm climate that reflects the typical characteristics of a tropical savanna environment.
Bissau experiences a wide temperature range throughout the year, with January seeing a minimum of 17°C (64°F) and April rising to a maximum of 41°C (106°F). For more detailed insights into the climate, you can refer to the monthly temperatures in Bissau here.
In Bissau, Guinea-Bissau, precipitation patterns are sharply defined, with a stark contrast between the dry and wet seasons. The year begins with complete dryness from January to April, during which no rainfall occurs. As May approaches, a slight increase in precipitation is observed, with only 1 mm (0.1 in) recorded. However, the arrival of the rainy season in June marks a dramatic shift, as rainfall accumulates rapidly, reaching 52 mm (2.0 in), and dramatically increasing in intensity throughout the following two months.
The peak of the rainy season occurs in August, when an astounding 539 mm (21.2 in) of rainfall is recorded over roughly 29 days. This is followed by substantial precipitation in September (369 mm or 14.5 in) and reduced amounts in October (134 mm or 5.3 in) and November (24 mm or 0.9 in). December returns to dryness, culminating in the region's characteristic seasonal cycle of intense precipitation during the summer months juxtaposed against prolonged dry spells at the beginning and end of the year.
In Bissau, Guinea-Bissau, sunshine duration exhibits clear seasonal trends, with a pronounced increase from the cooler winter months into the warmer summer period. Starting from 258 hours in January, the number of sunlit hours rises steadily, reaching a peak of 341 hours in May. This month highlights the transition into the dry season, emphasizing the region's abundant sunshine during this time. March also stands out with 334 hours, indicating that early spring is characterized by above-average sunlight, providing ample opportunity for outdoor activities before the onset of the rainy season.
As the rainy season begins in June, sunshine hours start to decline, recording 297 hours. July further intensifies this trend, with only 269 hours of sunshine, showcasing the impact of cloud cover and precipitation. The decrease continues into August (239 hours), marking it as the month with the least sunlight. Nevertheless, as the rains taper off in September and October, the sunshine hours gradually recover, culminating in 298 hours in October and 306 hours in November. December witnesses a resurgence in sunlight, with 321 hours, setting the stage for a return to the sunnier months ahead. Overall, Bissau's sunshine patterns illustrate a vibrant interplay between seasonal changes, highlighting the importance of sun exposure in shaping local climate experiences.
Bissau, Guinea-Bissau experiences consistently high levels of ultraviolet (UV) radiation throughout the year, with the UV Index reaching notably extreme levels during the peak sunny months. From January to February, the UV Index remains at 10, categorized as "very high," indicating a swift risk of harm from unprotected sun exposure, with a burn time of just 15 minutes. As the season transitions into March, the index escalates to 11, and continues rising until it peaks at 14 in both August and September. During these months, outdoor activities should be approached with caution, as the recommended burn time drops to just 10 minutes.
As the year progresses into the latter months, the UV Index experiences a slight decline, with October returning to 12 and November and December seeing a reduction to 9, categorized as "very high." Although the burn time in these months increases back to 15 minutes, the overall severity of UV exposure remains a concern for residents and visitors alike. Consequently, it is crucial for individuals in Bissau to adopt effective sun protection measures year-round, particularly during the peak months, to mitigate the risks associated with intense UV radiation.
UV Risk Categories
In Bissau, Guinea-Bissau, daylight duration remains relatively consistent throughout the year, with only slight variations that reflect the region's tropical positioning. From January to February, residents enjoy about 11 hours of daylight each day. As the year progresses into March, daylight begins to lengthen, reaching 12 hours in March and continuing this duration through June. This period allows for extensive outdoor activities and showcases the region's vibrant natural surroundings.
As the rainy season approaches, the daylight duration stabilizes at 12 hours from July to September, providing ample light for both leisure and agricultural pursuits. However, the trend shifts in October as the days begin to shorten again, returning to 11 hours of daylight by November and December. This consistent yet only mildly fluctuating pattern of daylight duration highlights Bissau's equatorial climate, where sunlight remains relatively abundant throughout the year, fostering a welcoming environment for daily life and outdoor endeavors.
Bissau, Guinea-Bissau, experiences a tropical savanna climate with distinct wet and dry seasons. Temperature ranges from a minimum of 17°C (64°F) in January to a maximum of 41°C (106°F) in April. The rainy season spans from June to September, with July and August receiving the highest precipitation, approximately 453 mm (17.8 in) and 539 mm (21.2 in) respectively. Sunshine is abundant, particularly from February to May, where hours of sunshine exceed 330 monthly. For detailed climate information, visit Bissau climate.
In conclusion, Bissau, Guinea-Bissau, presents a distinctive climate characterized by its tropical savanna features, intense seasonal variations in temperature, and a pronounced wet-dry cycle. The region enjoys significant sunshine year-round, with peak UV indices highlighting the importance of sun protection, especially during the extreme months. With consistent daylight duration averaging around 12 hours, Bissau fosters an environment conducive to outdoor activities and agricultural productivity. Understanding these climatic patterns not only aids residents and visitors in adapting to their surroundings but also emphasizes the need for sustainable practices in light of evolving climate challenges.