Waterloo weather in December

In December, Waterloo sees average daytime highs of 29°C and overnight lows near 25°C, with 42 mm of rain across 11.1 wet days and about 11.5 hours of daylight. It is the 5th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 46% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 11 h 30 min at the start of December to 11 h 30 min by month's end. Set against the rest of the year, December is Waterloo's 3rd-clearest and 10th-windiest month. For the whole year in context, see Waterloo's year-round climate.

Daytime high
29°
5th warmest
Overnight low
25°
9th coldest
Rainfall
42 mm
11.1 wet days
Daylight
11 h 30 min
7:03 AM – 6:34 PM
Cloud cover
46%
3rd clearest
Wind
7 km/h
10th windiest
Solar energy
4.99 kWh/m²
Travel score
5.5
out of 10

Waterloo is city in Sierra Leone.

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical December day in Waterloo reaches about 29°C in the afternoon and slips back to 25°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 30°C. Set against its neighbours, December runs on par with November and on par with January.

20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12925
22925
32925
42925
52925
62925
72925
82925
92925
102925
112925
122925
132925
142925
152925
162925
172925
182925
192925
202925
212925
222925
232925
242924
252924
262924
272924
282924
292924
302924
312924

How December really feels in Waterloo

Once humidity and wind are folded in, December averages 31 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
31
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in December is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Waterloo weather by month

How December compares with the rest of the year at a glance. December is the 5th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 24°164.111.66.2
Feb30° / 25°112.211.76.0
Mar30° / 25°204.711.95.6
Apr30° / 25°478.412.25.0
May29° / 25°21625.212.43.5
Jun28° / 24°42629.712.53.2
Jul27° / 24°60629.912.43.4
Aug26° / 24°70529.712.33.4
Sep27° / 24°50129.4123.3
Oct28° / 24°26629.611.83.3
Nov29° / 24°13024.811.63.7
Dec29° / 25°4211.111.55.5

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 46% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 23% of December, with mostly cloudy or overcast conditions the remaining 32%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16040
26040
36040
46238
56238
66337
76337
86535
96535
106634
116634
126733
136733
146733
156832
166931
176931
186931
197129
207129
217129
227228
237228
247327
257327
267327
277426
287426
297426
307426
317426

Chance of precipitation in December

Any precipitation

Waterloo gets around 42 mm of rain over 11.1 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 37% and peaks near 63% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
163
261
358
456
554
652
750
848
946
1044
1142
1240
1339
1437
1536
1634
1733
1832
1930
2029
2128
2227
2326
2425
2524
2623
2722
2821
2920
3019
3119

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

Most of December feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, December lands in the oppressive band about 76% of days. Sticky, muggy-or-worse air turns up on roughly 99% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1006436
2016435
3016633
4016732
5016831
6017029
7017128
8017227
9017326
10017425
11017524
12017623
13017722
14017821
15017920
16027820
17027919
18027919
19028018
20028018
21038017
22038017
23138016
24148015
25148114
26158014
27158113
28168112
29168211
30278110
3127829

Wind in December

Winds average 7 km/h in December.

Across December, daily wind ranges from about 6 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 11 h 30 min at the start of December to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 0 minutes over December. Sunrise moves from 6:56 AM to 7:10 AM, and sunset from 6:29 PM to 6:41 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.56:566:29
211.56:566:29
311.56:576:29
411.56:576:29
511.56:576:30
611.56:586:30
711.56:586:30
811.56:596:31
911.56:596:31
1011.57:006:32
1111.57:006:32
1211.57:016:32
1311.57:016:33
1411.57:026:33
1511.57:026:34
1611.57:036:34
1711.57:036:34
1811.57:046:35
1911.57:046:35
2011.57:056:36
2111.57:056:36
2211.57:066:37
2311.57:066:37
2411.57:076:38
2511.57:076:38
2611.57:086:39
2711.57:086:39
2811.57:096:40
2911.57:096:40
3011.57:096:41
3111.57:106:41

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.99 kWh/m².

For context, solar energy here swings from a low near 3.6 kWh/m² to a high of 6.01 kWh/m² in March across the year — December's 4.99 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
14.8Bright
24.8Bright
34.8Bright
44.8Bright
54.8Bright
64.8Bright
74.9Bright
84.9Bright
94.9Bright
104.9Bright
114.9Bright
124.9Bright
134.9Bright
145.0Bright
155.0Bright
165.0Bright
175.0Bright
185.0Bright
195.0Bright
205.0Bright
215.1Bright
225.1Bright
235.1Bright
245.1Bright
255.1Bright
265.2Bright
275.2Bright
285.2Bright
295.2Bright
305.2Bright
315.2Bright
Planning a trip in December

Hazard calendar for Waterloo

In seasonPeak

None of Waterloo's seasonal hazards are active in December. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Waterloo's monsoon runs June–September, when most of the year's rain falls.

Waterloo sees seasonal dust haze (February–April), heaviest in February.

Monsoon
Dust
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is December a good time to visit Waterloo?

Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.5
Sightseeing
4th-best month of the year
7.0
Beach & pool
4th-best month of the year

December is a reasonable time to visit Waterloo for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Waterloo in December

From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In December, Waterloo sees daytime highs around 29°C and nights near 25°C. Pack light clothes. Worth having: rain gear and sun protection. About 11 days see rain.

light clothesrain gearsun protection

Sea temperature near Waterloo in December

The nearest coast averages about 29°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 25 km away) is warmest in May at about 29°C and coldest in August near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Warm
Feb28Warm
Mar28Warm
Apr28Warm
May29Tropical
Jun28Tropical
Jul27Warm
Aug27Warm
Sep27Warm
Oct28Warm
Nov29Tropical
Dec29Tropical

UV index in Waterloo in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Waterloo peaks around August 20 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 8 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highAug 20UV 13Dec 15UV 8
UV index (midday)Level
Jan9Very high
Feb12Extreme
Mar12Extreme
Apr11Extreme
May12Extreme
Jun12Extreme
Jul11Extreme
Aug13Extreme
Sep12Extreme
Oct11Extreme
Nov9Very high
Dec8Very high

Air quality in Waterloo in December

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.

Air quality in Waterloo is worst in April — around 217 µg/m³ PM2.5 (very unhealthy), about 19.6× the cleanest month (August, 11 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0306090120150180210JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyVery unhealthyUnhealthyModerateGoodModeratePoorApr 14200 µg/m³Aug 2011 µg/m³
PM2.5 (µg/m³)Level
Jan72Unhealthy
Feb78Unhealthy
Mar106Unhealthy
Apr217Very unhealthy
May43Poor
Jun20Moderate
Jul14Moderate
Aug11Good
Sep12Moderate
Oct18Moderate
Nov27Moderate
Dec54Poor
Location & terrain

Where is Waterloo?

Waterloo sits at 8.3°N, 13.1°W, 23 m above sea level, in Sierra Leone. The nearest listed city is Freetown, 24 km away.

FreetownGoderichPort LokoLunsarMile 91NjalaForécariahMakeni

Topography around Waterloo

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Waterloo.

Within 3 km, the terrain around Waterloo has significant variations in elevation — a maximum elevation change of 419 m around an average of 52 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 899 m; within 80 km, large variations in elevation — a maximum elevation change of 885 m.

The land around Waterloo is covered by artificial surfaces (46%), grassland (23%) and trees (20%) within 3 km, trees (48%) within 16 km, and water (41%) and trees (39%) within 80 km.

3 km
419 m
16 km
899 m
80 km
885 m
treesshrubsgrasslandartificial surfaceswaterwetlandmangroves
December weather nearby: Freetown 24 km · Goderich 26 km · Port Loko 57 km · Lunsar 70 km · Mile 91 95 km · Njala 117 km · Forécariah 121 km · Makeni 128 km

Sierra Leone travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type D / G
230 V · 50 Hz
Prices
≈ 24% of US
price level, 2025
GDP per capita
$846
2025
Happiness
3.3 / 10
World Happiness, 2025
Safe drinking water
11%
of population, 2024
Homicide rate
2.2
per 100k, 2020
Road deaths
33
per 100k/yr, 2019
Income group
Low
World Bank
Religion
Muslim 77%Christian 23%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Waterloo (8.3389°, -13.0709°, elevation 23 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).