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Bo, Sierra Leone climate
Am Tropical monsoon
Bo has a remarkably steady tropical climate (Tropical monsoon, Köppen Am). The hottest month is March with an average daily high near 35°C, while the coldest is August averaging around 22°C at night. Precipitation totals about 2564 mm a year and is strongly seasonal — August alone averages 481 mm while January barely receives 20 mm.
Temperature & precipitation
Daily high–low temperature range with the monthly average, plus monthly precipitation · 1991–2020 normals · hover a month for the exact figuresHours of sunshine per day
Estimated sunny hours each month — daylight length × clear-sky fraction · 1991–2020 monthly cloud cover (NASA POWER)Bo climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 32 | 34 | 35 | 34 | 32 | 30 | 28 | 28 | 28 | 29 | 30 | 31 |
| Avg temp (°C) | 26 | 28 | 30 | 29 | 28 | 27 | 25 | 25 | 25 | 26 | 26 | 26 |
| Avg low (°C) | 20 | 22 | 24 | 24 | 24 | 23 | 22 | 22 | 22 | 23 | 23 | 21 |
| Precipitation (mm) | 20 | 23 | 63 | 127 | 256 | 343 | 406 | 481 | 443 | 258 | 113 | 31 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°C) | 32 | 34 | 35 | 34 | 32 | 30 |
| Avg temp (°C) | 26 | 28 | 30 | 29 | 28 | 27 |
| Avg low (°C) | 20 | 22 | 24 | 24 | 24 | 23 |
| Precipitation (mm) | 20 | 23 | 63 | 127 | 256 | 343 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°C) | 28 | 28 | 28 | 29 | 30 | 31 |
| Avg temp (°C) | 25 | 25 | 25 | 26 | 26 | 26 |
| Avg low (°C) | 22 | 22 | 22 | 23 | 23 | 21 |
| Precipitation (mm) | 406 | 481 | 443 | 258 | 113 | 31 |
How often — frequency of weather events
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Days with high ≥ 32°C (days) | 11 | 21 | 26 | 23 | 14 | 5 | 0.8 | 0.2 | 0.5 | 0.9 | 3 | 6 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Days with high ≥ 32°C (days) | 11 | 21 | 26 | 23 | 14 | 5 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Days with high ≥ 32°C (days) | 0.8 | 0.2 | 0.5 | 0.9 | 3 | 6 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 34 | 37 | 50 | 62 | 75 | 78 | 85 | 88 | 84 | 77 | 63 | 41 |
| Relative humidity (%) | 71 | 70 | 67 | 70 | 80 | 87 | 89 | 91 | 91 | 89 | 85 | 77 |
| Wind speed (mph) | 2.8 | 3.2 | 3.6 | 3.5 | 3.2 | 3.6 | 4.3 | 4.5 | 3.7 | 2.8 | 2.2 | 2.5 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 34 | 37 | 50 | 62 | 75 | 78 |
| Relative humidity (%) | 71 | 70 | 67 | 70 | 80 | 87 |
| Wind speed (mph) | 2.8 | 3.2 | 3.6 | 3.5 | 3.2 | 3.6 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 85 | 88 | 84 | 77 | 63 | 41 |
| Relative humidity (%) | 89 | 91 | 91 | 89 | 85 | 77 |
| Wind speed (mph) | 4.3 | 4.5 | 3.7 | 2.8 | 2.2 | 2.5 |
Methodology & sources
Temperature & precipitation — modelled for this location from ERA5-Land reanalysis, a ~9 km global grid, because no long-record weather station is close enough to use.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.