Waterloo weather in September
In September, Waterloo sees average daytime highs of 27°C and overnight lows near 24°C, with 501 mm of rain across 29.4 wet days and about 12 hours of daylight. It is the 10th-warmest and 3rd-wettest month of the year here.
Day-to-day highs hold fairly steady near 27°C through the month. The sky is clear or mostly clear about 1% of the time in September, and the air most often feels oppressive.
Daylight stretches from about 12 h 12 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Waterloo's 10th-clearest and 6th-windiest month. For the whole year in context, see Waterloo's year-round climate.
- Daytime high
- 27°
- 10th warmest
- Overnight low
- 24°
- 3rd coldest
- Rainfall
- 501 mm
- 29.4 wet days
- Daylight
- 12 hours
- 6:45 AM – 6:48 PM
- Cloud cover
- 87%
- 10th clearest
- Wind
- 9 km/h
- 6th windiest
- Solar energy
- 4.08 kWh/m²
- Travel score
- 3.3
- out of 10
Waterloo is city in Sierra Leone.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in September
Day-to-day highs hold fairly steady near 27°C through the month.
A typical September day in Waterloo reaches about 27°C in the afternoon and slips back to 24°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 28°C. Set against its neighbours, September runs on par with August and about 1°C cooler than October.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 27 | 28 | 28 | 28 | 28 |
| Avg low (°C) | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 27 | 24 |
| 2 | 27 | 24 |
| 3 | 27 | 24 |
| 4 | 27 | 24 |
| 5 | 27 | 24 |
| 6 | 27 | 24 |
| 7 | 27 | 24 |
| 8 | 27 | 24 |
| 9 | 27 | 24 |
| 10 | 27 | 24 |
| 11 | 27 | 24 |
| 12 | 27 | 24 |
| 13 | 27 | 24 |
| 14 | 27 | 24 |
| 15 | 27 | 24 |
| 16 | 27 | 24 |
| 17 | 27 | 24 |
| 18 | 27 | 24 |
| 19 | 27 | 24 |
| 20 | 27 | 24 |
| 21 | 27 | 24 |
| 22 | 27 | 24 |
| 23 | 27 | 24 |
| 24 | 27 | 24 |
| 25 | 27 | 24 |
| 26 | 27 | 24 |
| 27 | 28 | 24 |
| 28 | 28 | 24 |
| 29 | 28 | 24 |
| 30 | 28 | 24 |
How September really feels in Waterloo
Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.
September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.
Waterloo weather by month
How September compares with the rest of the year at a glance. September is the 10th-warmest and 3rd-wettest month here — the current month is highlighted below.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 30° / 24° | 16 | 4.1 | 11.6 | 6.2 |
| Feb | 30° / 25° | 11 | 2.2 | 11.7 | 6.0 |
| Mar | 30° / 25° | 20 | 4.7 | 11.9 | 5.6 |
| Apr | 30° / 25° | 47 | 8.4 | 12.2 | 5.0 |
| May | 29° / 25° | 216 | 25.2 | 12.4 | 3.5 |
| Jun | 28° / 24° | 426 | 29.7 | 12.5 | 3.2 |
| Jul | 27° / 24° | 606 | 29.9 | 12.4 | 3.4 |
| Aug | 26° / 24° | 705 | 29.7 | 12.3 | 3.4 |
| Sep | 27° / 24° | 501 | 29.4 | 12 | 3.3 |
| Oct | 28° / 24° | 266 | 29.6 | 11.8 | 3.3 |
| Nov | 29° / 24° | 130 | 24.8 | 11.6 | 3.7 |
| Dec | 29° / 25° | 42 | 11.1 | 11.5 | 5.5 |
Cloud cover in September
The sky is clear or mostly clear about 1% of the time in September.
Beyond those clear spells, partly cloudy skies cover about 6% of September, with mostly cloudy or overcast conditions the remaining 93%.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 4 | 4 | 5 | 5 | 5 | 5 | 5 | 4 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 6 | 6 | 6 | 7 | 7 | 8 | 8 | 8 | 9 | 10 | 10 | 10 | 11 | 11 | 11 |
| Cloudier (%) | 96 | 96 | 95 | 95 | 95 | 95 | 95 | 96 | 95 | 95 | 95 | 95 | 95 | 95 | 95 | 94 | 94 | 94 | 93 | 93 | 92 | 92 | 92 | 91 | 90 | 90 | 90 | 89 | 89 | 89 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 4 | 96 |
| 2 | 4 | 96 |
| 3 | 5 | 95 |
| 4 | 5 | 95 |
| 5 | 5 | 95 |
| 6 | 5 | 95 |
| 7 | 5 | 95 |
| 8 | 4 | 96 |
| 9 | 5 | 95 |
| 10 | 5 | 95 |
| 11 | 5 | 95 |
| 12 | 5 | 95 |
| 13 | 5 | 95 |
| 14 | 5 | 95 |
| 15 | 5 | 95 |
| 16 | 6 | 94 |
| 17 | 6 | 94 |
| 18 | 6 | 94 |
| 19 | 7 | 93 |
| 20 | 7 | 93 |
| 21 | 8 | 92 |
| 22 | 8 | 92 |
| 23 | 8 | 92 |
| 24 | 9 | 91 |
| 25 | 10 | 90 |
| 26 | 10 | 90 |
| 27 | 10 | 90 |
| 28 | 11 | 89 |
| 29 | 11 | 89 |
| 30 | 11 | 89 |
Chance of precipitation in September
Waterloo gets around 501 mm of rain over 29.4 wet days in September. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 98% and peaks near 98% on the wettest days.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 97 | 97 |
| Rain chance (%) | |
|---|---|
| 1 | 98 |
| 2 | 98 |
| 3 | 98 |
| 4 | 98 |
| 5 | 98 |
| 6 | 98 |
| 7 | 98 |
| 8 | 98 |
| 9 | 98 |
| 10 | 98 |
| 11 | 98 |
| 12 | 98 |
| 13 | 98 |
| 14 | 98 |
| 15 | 98 |
| 16 | 98 |
| 17 | 98 |
| 18 | 98 |
| 19 | 98 |
| 20 | 98 |
| 21 | 98 |
| 22 | 98 |
| 23 | 98 |
| 24 | 98 |
| 25 | 98 |
| 26 | 98 |
| 27 | 98 |
| 28 | 98 |
| 29 | 97 |
| 30 | 97 |
Humidity in September
Most of September feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, September lands in the oppressive band about 99% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Oppressive (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 99 | 99 | 99 | 99 | 99 | 99 | 99 | 99 | 99 | 99 | 99 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 98 | 97 | 97 |
| Miserable (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 3 | 3 |
| Oppressive (%) | Miserable (%) | |
|---|---|---|
| 1 | 100 | 0 |
| 2 | 100 | 0 |
| 3 | 100 | 0 |
| 4 | 100 | 0 |
| 5 | 100 | 0 |
| 6 | 100 | 0 |
| 7 | 100 | 0 |
| 8 | 99 | 1 |
| 9 | 99 | 1 |
| 10 | 99 | 1 |
| 11 | 99 | 1 |
| 12 | 99 | 1 |
| 13 | 99 | 1 |
| 14 | 99 | 1 |
| 15 | 99 | 1 |
| 16 | 99 | 1 |
| 17 | 99 | 1 |
| 18 | 99 | 1 |
| 19 | 98 | 2 |
| 20 | 98 | 2 |
| 21 | 98 | 2 |
| 22 | 98 | 2 |
| 23 | 98 | 2 |
| 24 | 98 | 2 |
| 25 | 98 | 2 |
| 26 | 98 | 2 |
| 27 | 98 | 2 |
| 28 | 98 | 2 |
| 29 | 97 | 3 |
| 30 | 97 | 3 |
Wind in September
Winds average 9 km/h in September.
Across September, daily wind ranges from about 8 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 11 | 11 | 11 | 11 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| 1 | 11 | calm |
| 2 | 11 | calm |
| 3 | 11 | calm |
| 4 | 11 | calm |
| 5 | 10 | calm |
| 6 | 10 | calm |
| 7 | 10 | calm |
| 8 | 10 | calm |
| 9 | 10 | calm |
| 10 | 10 | calm |
| 11 | 10 | calm |
| 12 | 10 | calm |
| 13 | 10 | calm |
| 14 | 9 | calm |
| 15 | 9 | calm |
| 16 | 9 | calm |
| 17 | 9 | calm |
| 18 | 9 | calm |
| 19 | 9 | calm |
| 20 | 9 | calm |
| 21 | 9 | calm |
| 22 | 8 | calm |
| 23 | 8 | calm |
| 24 | 8 | calm |
| 25 | 8 | calm |
| 26 | 8 | calm |
| 27 | 8 | calm |
| 28 | 8 | calm |
| 29 | 8 | calm |
| 30 | 8 | calm |
Sunrise & sunset in September
Daylight runs from about 12 h 12 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.
Days shrink by about 18 minutes over September. Sunrise moves from 6:47 AM to 6:44 AM, and sunset from 6:57 PM to 6:40 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 12.2 | 12.2 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.1 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 11.9 | 11.9 |
| Sunrise (AM) | 6:47 | 6:47 | 6:47 | 6:47 | 6:47 | 6:47 | 6:46 | 6:46 | 6:46 | 6:46 | 6:46 | 6:46 | 6:46 | 6:46 | 6:45 | 6:45 | 6:45 | 6:45 | 6:45 | 6:45 | 6:45 | 6:44 | 6:44 | 6:44 | 6:44 | 6:44 | 6:44 | 6:44 | 6:44 | 6:44 |
| Sunset (PM) | 6:57 | 6:56 | 6:56 | 6:55 | 6:55 | 6:54 | 6:53 | 6:53 | 6:52 | 6:52 | 6:51 | 6:50 | 6:50 | 6:49 | 6:49 | 6:48 | 6:47 | 6:47 | 6:46 | 6:46 | 6:45 | 6:44 | 6:44 | 6:43 | 6:43 | 6:42 | 6:41 | 6:41 | 6:40 | 6:40 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 12.2 | 6:47 | 6:57 |
| 2 | 12.2 | 6:47 | 6:56 |
| 3 | 12.1 | 6:47 | 6:56 |
| 4 | 12.1 | 6:47 | 6:55 |
| 5 | 12.1 | 6:47 | 6:55 |
| 6 | 12.1 | 6:47 | 6:54 |
| 7 | 12.1 | 6:46 | 6:53 |
| 8 | 12.1 | 6:46 | 6:53 |
| 9 | 12.1 | 6:46 | 6:52 |
| 10 | 12.1 | 6:46 | 6:52 |
| 11 | 12.1 | 6:46 | 6:51 |
| 12 | 12.1 | 6:46 | 6:50 |
| 13 | 12.1 | 6:46 | 6:50 |
| 14 | 12.1 | 6:46 | 6:49 |
| 15 | 12.1 | 6:45 | 6:49 |
| 16 | 12.0 | 6:45 | 6:48 |
| 17 | 12.0 | 6:45 | 6:47 |
| 18 | 12.0 | 6:45 | 6:47 |
| 19 | 12.0 | 6:45 | 6:46 |
| 20 | 12.0 | 6:45 | 6:46 |
| 21 | 12.0 | 6:45 | 6:45 |
| 22 | 12.0 | 6:44 | 6:44 |
| 23 | 12.0 | 6:44 | 6:44 |
| 24 | 12.0 | 6:44 | 6:43 |
| 25 | 12.0 | 6:44 | 6:43 |
| 26 | 12.0 | 6:44 | 6:42 |
| 27 | 12.0 | 6:44 | 6:41 |
| 28 | 12.0 | 6:44 | 6:41 |
| 29 | 11.9 | 6:44 | 6:40 |
| 30 | 11.9 | 6:44 | 6:40 |
Solar energy in September
Average shortwave solar energy reaching the ground each day in September, about 4.08 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 — September's 4.08 kWh/m² sits near the bottom.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 3.8 | 3.8 | 3.8 | 3.9 | 3.9 | 3.9 | 3.9 | 3.9 | 3.9 | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 | 4.1 | 4.1 | 4.1 | 4.1 | 4.2 | 4.2 | 4.2 | 4.2 | 4.3 | 4.3 | 4.3 | 4.3 | 4.3 | 4.3 | 4.3 | 4.4 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 3.8 | Moderate |
| 2 | 3.8 | Moderate |
| 3 | 3.8 | Moderate |
| 4 | 3.9 | Moderate |
| 5 | 3.9 | Moderate |
| 6 | 3.9 | Moderate |
| 7 | 3.9 | Moderate |
| 8 | 3.9 | Moderate |
| 9 | 3.9 | Moderate |
| 10 | 4.0 | Moderate |
| 11 | 4.0 | Moderate |
| 12 | 4.0 | Bright |
| 13 | 4.0 | Bright |
| 14 | 4.0 | Bright |
| 15 | 4.1 | Bright |
| 16 | 4.1 | Bright |
| 17 | 4.1 | Bright |
| 18 | 4.1 | Bright |
| 19 | 4.2 | Bright |
| 20 | 4.2 | Bright |
| 21 | 4.2 | Bright |
| 22 | 4.2 | Bright |
| 23 | 4.3 | Bright |
| 24 | 4.3 | Bright |
| 25 | 4.3 | Bright |
| 26 | 4.3 | Bright |
| 27 | 4.3 | Bright |
| 28 | 4.3 | Bright |
| 29 | 4.3 | Bright |
| 30 | 4.4 | Bright |
Hazard calendar for Waterloo
In September, Waterloo sits inside its monsoon season. The full year is below, with each hazard's peak months called out.
Waterloo's monsoon runs June–September, when most of the year's rain falls.
Waterloo sees seasonal dust haze (February–April), heaviest in February.
Is September a good time to visit Waterloo?
Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
September is a weaker month for outdoor sightseeing in Waterloo.
What to pack for Waterloo in September
From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In September, Waterloo sees daytime highs around 27°C and nights near 24°C. Pack light clothes and rain gear. About 29 days see rain.
Sea temperature near Waterloo in September
The nearest coast averages about 27°C in September — 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 28 | 28 | 28 | 28 | 29 | 28 | 27 | 27 | 27 | 28 | 29 | 29 |
| Comfort | Warm | Warm | Warm | Warm | Tropical | Tropical | Warm | Warm | Warm | Warm | Tropical | Tropical |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 28 | Warm |
| Feb | 28 | Warm |
| Mar | 28 | Warm |
| Apr | 28 | Warm |
| May | 29 | Tropical |
| Jun | 28 | Tropical |
| Jul | 27 | Warm |
| Aug | 27 | Warm |
| Sep | 27 | Warm |
| Oct | 28 | Warm |
| Nov | 29 | Tropical |
| Dec | 29 | Tropical |
UV index in Waterloo in September
Clear-sky midday UV in September peaks around 12 (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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 9 | 12 | 12 | 11 | 12 | 12 | 11 | 13 | 12 | 11 | 9 | 8 |
| Level | Very high | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Very high | Very high |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 9 | Very high |
| Feb | 12 | Extreme |
| Mar | 12 | Extreme |
| Apr | 11 | Extreme |
| May | 12 | Extreme |
| Jun | 12 | Extreme |
| Jul | 11 | Extreme |
| Aug | 13 | Extreme |
| Sep | 12 | Extreme |
| Oct | 11 | Extreme |
| Nov | 9 | Very high |
| Dec | 8 | Very high |
Air quality in Waterloo in September
Average fine-particle pollution (PM2.5) through the year — so you can see where September 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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 72 | 78 | 106 | 217 | 43 | 20 | 14 | 11 | 12 | 18 | 27 | 54 |
| Level | Unhealthy | Unhealthy | Unhealthy | Very unhealthy | Poor | Moderate | Moderate | Good | Moderate | Moderate | Moderate | Poor |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 72 | Unhealthy |
| Feb | 78 | Unhealthy |
| Mar | 106 | Unhealthy |
| Apr | 217 | Very unhealthy |
| May | 43 | Poor |
| Jun | 20 | Moderate |
| Jul | 14 | Moderate |
| Aug | 11 | Good |
| Sep | 12 | Moderate |
| Oct | 18 | Moderate |
| Nov | 27 | Moderate |
| Dec | 54 | Poor |
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.
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.
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
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).