Bissau, Guinea-Bissau Climate & Monthly Averages
The climate of Bissau
Bissau has one of the steadier climates in our dataset. Average highs move only 2°C across the whole year - from 83°F (28°C) in August to 88°F (31°C) in June - so the practical difference between seasons here is rainfall and daylight, not warmth.
Climate quick facts
- Hottest month: June - highs near 88°F (31°C)
- Coldest month: August - highs near 83°F (28°C)
- Decade extremes (2015-2024): 105°F (40°C) high · 65°F (18°C) low
- Wettest month: August (29 rainy days) · Sunniest: April (11.7 h sun/day)
- Climate type: tropical wet-and-dry
- Annual swing: 2°C between the average warmest and coolest month · day to night: 8°C
- Months averaging 30°C or hotter: 9
- Average humidity: 67%
Temperatures through the year
7 months average under 20 mm of rain, the longest unbroken stretch running November through May. August sits at the other end of the year: 83°F (28°C) by day, 76°F (25°C) at night. Warmth peaks in June: highs of 88°F (31°C), lows of 78°F (25°C). The gridded 2015-2024 daily record for this location tops out at 105°F (40°C) and bottoms at 65°F (18°C) - decade extremes, not all-time station records. Relative humidity averages 67% across the year, drier than about 75% of the cities we track.
Rain, sun and snow
April is the brightest month at 11.7 hours of sun a day, against an annual average of 9.9. Rainfall is strongly seasonal: 85% of the annual total falls in the July to September window, leaving January at less than 1 mm. Between the average June and the average August lie 2°C, a narrower spread than all but 3% of the 3496 cities in our dataset.
How Bissau compares
- 85% of the year's precipitation falls in its wettest three months - more seasonal than any other city in our 3496-city dataset.
- Bissau averages 81°F (27°C) across the year - warmer than 94% of the 3496 cities we track.
Ranked against every city in our dataset, each measured on the same ten-year window.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 91° | 70° | 0 | 0.0 in | 10.5 h/day | 11.5 h | 0% | 43% |
| February | 93° | 71° | 0 | 0.0 in | 10.8 h/day | 11.7 h | 0% | 44% |
| March | 93° | 73° | 0 | 0.0 in | 11.2 h/day | 12.0 h | 0% | 52% |
| April | 91° | 74° | 0 | 0.0 in | 11.7 h/day | 12.4 h | 0% | 60% |
| May | 90° | 75° | 1 | 0.1 in | 11.2 h/day | 12.7 h | 2% | 66% |
| June | 88° | 78° | 10 | 2.4 in | 10.2 h/day | 12.8 h | 32% | 76% |
| July | 83° | 77° | 28 | 16.5 in | 7.8 h/day | 12.8 h | 90% | 85% |
| August | 83° | 76° | 29 | 19.9 in | 7.5 h/day | 12.5 h | 93% | 87% |
| September | 84° | 76° | 26 | 13.2 in | 8.2 h/day | 12.2 h | 88% | 87% |
| October | 87° | 77° | 20 | 5.7 in | 9.7 h/day | 11.8 h | 65% | 85% |
| November | 89° | 75° | 4 | 0.7 in | 10.4 h/day | 11.6 h | 12% | 72% |
| December | 91° | 71° | 0 | 0.0 in | 10.1 h/day | 11.4 h | 1% | 49% |
Bissau month by month
Average high and low for each month, with the bar showing where it sits in Bissau's year (left is the coldest night, right is the warmest afternoon).
January
- Rain
- 0 days
- Sunshine
- 10.5 h
- Daylight
- 11.5 h
February
- Rain
- 0 days
- Sunshine
- 10.8 h
- Daylight
- 11.7 h
March
- Rain
- 0 days
- Sunshine
- 11.2 h
- Daylight
- 12.0 h
April
- Rain
- 0 days
- Sunshine
- 11.7 h
- Daylight
- 12.4 h
May
- Rain
- 1 day
- Sunshine
- 11.2 h
- Daylight
- 12.7 h
June
- Rain
- 10 days
- Sunshine
- 10.2 h
- Daylight
- 12.8 h
July
- Rain
- 28 days
- Sunshine
- 7.8 h
- Daylight
- 12.8 h
August
- Rain
- 29 days
- Sunshine
- 7.5 h
- Daylight
- 12.5 h
September
- Rain
- 26 days
- Sunshine
- 8.2 h
- Daylight
- 12.2 h
October
- Rain
- 20 days
- Sunshine
- 9.7 h
- Daylight
- 11.8 h
November
- Rain
- 4 days
- Sunshine
- 10.4 h
- Daylight
- 11.6 h
December
- Rain
- 0 days
- Sunshine
- 10.1 h
- Daylight
- 11.4 h
Warmer places to go, by month: January · February · March · April · May · June · July · August · September · October · November · December
Seasons in Bissau
March through May
March through May in Bissau is hot, with daytime highs averaging 91°F (33°C) and nights around 74°F (23°C); precipitation is essentially absent. Daylight is generous - around 11.4 hours of sun a day.
June through August
Through June through August, Bissau brings hot afternoons: 85°F (29°C) by day, 77°F (25°C) after dark, and rain falls on around 66 of the 90 days.
September through November
September through November in Bissau runs hot, with daytime highs averaging 87°F (30°C) and nights around 76°F (25°C); rain falls on around 50 of the 90 days.
December through February
Through December through February, Bissau brings serious heat: 92°F (33°C) by day, 71°F (22°C) after dark, and precipitation is essentially absent. Daylight is generous - around 10.5 hours of sun a day.
Climate questions, answered
When is the rainy season in Bissau?
Is Bissau cold in winter?
How hot does Bissau get in summer?
How sunny is Bissau?
How humid does Bissau get?
Best time to visit Bissau
Aim for November to January and April to May if you get the choice: the rains have stopped and the heat has not yet peaked, and highs average 91°F (33°C) against roughly 1 wet days a month. For the same question asked the other way round, see where else is warm in November.
Pack for Bissau with light clothing for the warm months and a compact umbrella or rain shell. June nights average 78°F (25°C), so evenings rarely match the afternoons.
Bissau temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need the precipitation in other units? The mm-to-inches rainfall converter handles it.