Climate averages 1991–2020
Boma weather
in September.
A hot, very dry month: the 9th warmest and the 4th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
September is a hot month in Boma: daytime highs average 28.2°C and nights cool to about 20.8°C. By daytime temperature it is the 9th warmest of the 12 months.
Expect about 12 mm of rain on roughly 3 days, which makes September a very dry month (the 4th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 04 min on an average September day.
The nearest other city in this atlas is Matadi (45 km away). In September its highs average 27.7°C, 0.5°C cooler than Boma, with 12 mm of rain.
Among the 60 cities listed in the Democratic Republic of the Congo, Boma ranks joint 48th of 60 for the warmest September highs and joint 11th of 60 for the driest September (rainfall, lowest first). The mean September high of those 60 cities is 29.6°C; Boma is 1.4°C cooler than that mean.
From September to October, average highs rise by 1.5°C to 29.7°C, and monthly rainfall rises from 12 mm to 52 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Boma climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 30.1°C23.5°C | 23.5°C | 176 | 21.9 | 12.412 h |
| February | 30.5°C23.9°C | 23.9°C | 146 | 19.3 | 12.312 h |
| March | 30.8°C24.2°C | 24.2°C | 147 | 20.4 | 12.112 h |
| April | 30.3°C24.2°C | 24.2°C | 184 | 22.1 | 12.012 h |
| May | 29.5°C23.3°C | 23.3°C | 63 | 11.6 | 11.912 h |
| June | 28.0°C20.4°C | 20.4°C | 3.1 | 0.4 | 11.812 h |
| July | 27.4°C18.8°C | 18.8°C | 2.2 | 0.1 | 11.812 h |
| August | 27.2°C19.2°C | 19.2°C | 5.5 | 0.8 | 11.912 h |
| September, selected | 28.2°C20.8°C | 20.8°C | 12 | 2.6 | 12.112 h |
| October | 29.7°C22.7°C | 22.7°C | 52 | 10.4 | 12.212 h |
| November | 30.1°C23.5°C | 23.5°C | 155 | 22.0 | 12.412 h |
| December | 29.8°C23.5°C | 23.5°C | 187 | 23.4 | 12.512 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Matadi in SeptemberDemocratic Republic of the Congo · 45 kmHigh 27.7°C · Low 20.3°C · 12 mm rain
- Moanda, Democratic Republic of the Congo in SeptemberDemocratic Republic of the Congo · 76 kmHigh 25.6°C · Low 21.5°C · 4.2 mm rain
- Soyo in SeptemberAngola · 82 kmHigh 24.4°C · Low 22.1°C · 2.1 mm rain
- Cabinda in SeptemberAngola · 100 kmHigh 25.7°C · Low 22.0°C · 9.0 mm rain
- Mbanza Kongo in SeptemberAngola · 139 kmHigh 27.9°C · Low 18.9°C · 11 mm rain
- Kimpese in SeptemberDemocratic Republic of the Congo · 156 kmHigh 29.3°C · Low 20.4°C · 11 mm rain
- Pointe-Noire in SeptemberRepublic of the Congo · 178 kmHigh 26.1°C · Low 21.7°C · 6.3 mm rain
- Nkayi in SeptemberRepublic of the Congo · 187 kmHigh 29.8°C · Low 21.4°C · 11 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Boma) is explained once on the Boma year overview and on the Sources, method and limits page.