Bo climate

Name: Bo
Address: SL

Bo is warmest in February, with average highs of 34 °C, and coldest in January, when nights average 22 °C. August is the wettest month (479 mm) and January the driest (17 mm). Figures are 1991–2020 climate normals.

Across a full year Bo averages 2,509 mm of rain and 353 days above 25 °C.

Sierra Leone · population 233,684 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month February 34 °C
Coldest month January 22 °C
Driest month January 17 mm
Wettest month August 479 mm
Least cloud January 42 % cloud
Hottest on record February 41 °C
Coldest on record January 17 °C

What to expectBo through the year

Bo has a clear annual cycle: average daily highs run from 33 °C in January to 34 °C in February, a swing of 3.9 °C in mean temperature across the year.

Counted across a normal year, 353 days a year reach 25 °C, 189 of them reach 30 °C. The warmest reading in the 1991–2020 record is 41 °C, in February.

Rain is strongly seasonal. August averages 479 mm against 17 mm in January — 28 times as much. Planning around the dry months matters more here than planning around temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	33.2 °C	17 mm	42 %
February	34.4 °C	20 mm	47 %
March	33.9 °C	61 mm	61 %
April	32.2 °C	120 mm	74 %
May	30.4 °C	248 mm	86 %
June	29.0 °C	342 mm	86 %
July	27.7 °C	419 mm	89 %
August	27.3 °C	479 mm	92 %
September	28.1 °C	424 mm	89 %
October	28.9 °C	244 mm	85 %
November	29.5 °C	109 mm	73 %
December	31.0 °C	27 mm	54 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C
January	33.2 °C	21.7 °C	26.5 °C	38.6 °C	16.8 °C	31	29
February	34.4 °C	22.8 °C	27.5 °C	40.6 °C	18.8 °C	28	28
March	33.9 °C	23.6 °C	27.5 °C	40.2 °C	19.1 °C	31	30
April	32.2 °C	23.7 °C	26.8 °C	37.8 °C	20.9 °C	30	27
May	30.4 °C	23.2 °C	25.7 °C	35.4 °C	21.1 °C	31	21
June	29.0 °C	22.4 °C	24.6 °C	32.9 °C	20.3 °C	29	9
July	27.7 °C	21.9 °C	23.9 °C	31.6 °C	19.1 °C	28	2
August	27.3 °C	21.8 °C	23.6 °C	31.8 °C	18.9 °C	26	2
September	28.1 °C	22.0 °C	24.0 °C	34.6 °C	20.5 °C	27	4
October	28.9 °C	22.1 °C	24.5 °C	32.1 °C	20.3 °C	31	6
November	29.5 °C	22.4 °C	25.0 °C	32.7 °C	20.5 °C	30	9
December	31.0 °C	22.1 °C	25.7 °C	35.7 °C	17.2 °C	31	23

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind
January	17 mm	4	12 h/day	42 %	72 %	11 km/h
February	20 mm	5	12 h/day	47 %	71 %	12 km/h
March	61 mm	11	12 h/day	61 %	75 %	12 km/h
April	120 mm	18	12 h/day	74 %	82 %	9.8 km/h
May	248 mm	27	12 h/day	86 %	89 %	8.6 km/h
June	342 mm	29	13 h/day	86 %	90 %	9.0 km/h
July	419 mm	29	13 h/day	89 %	91 %	9.6 km/h
August	479 mm	29	12 h/day	92 %	92 %	10 km/h
September	424 mm	29	12 h/day	89 %	92 %	8.9 km/h
October	244 mm	29	12 h/day	85 %	91 %	7.5 km/h
November	109 mm	19	12 h/day	73 %	90 %	7.2 km/h
December	27 mm	6	12 h/day	54 %	83 %	9.0 km/h

How Bo compares

The same four figures for nearby destinations, so the numbers above have something to be read against. Summer high is the warmest month's average high; winter low is the coldest month's average low.

Destination	Summer high	Winter low	Rain per year	Days above 25 °C
Bo	34 °C	22 °C	2,509 mm	353
Kenema · Sierra Leone	34 °C	22 °C	2,287 mm	352
Freetown · Sierra Leone	28 °C	24 °C	3,006 mm	360
Monrovia · Liberia	29 °C	23 °C	3,443 mm	356
Kindia · Guinea	36 °C	20 °C	1,716 mm	349
Manéah · Guinea	33 °C	21 °C	2,580 mm	356
Conakry · Guinea	30 °C	23 °C	2,710 mm	360

Planning a trip? See the best time to visit Bo.

QuestionsCommon questions about Bo’s climate

When is the best time to visit Bo?

That depends on what you want, so the honest answer is a comparison rather than a single month. July, August, September sit closest to 20 °C on average, February is the warmest month and January the driest. The month-by-month table above has the full picture.

How hot does Bo get?

In February, the warmest month, daily highs average 34 °C. About 189 days a year pass 30 °C. The highest value in the 1991–2020 record is 41 °C.

How cold does it get in winter?

Nights average 22 °C in January, the coldest month. Freezing nights are not part of a normal year here.

Which month is wettest in Bo?

August, averaging 479 mm over 29 days with rain. The driest month is January with 17 mm. The year as a whole averages 2,509 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Bo rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.