Santa Helena weather in December
In December, Santa Helena sees average daytime highs of 31°C and overnight lows near 22°C, with 154 mm of rain across 14.4 wet days and about 13.5 hours of daylight. It is the 3rd-warmest and 2nd-wettest month of the year here.
Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 34% of the time in December, and the air most often feels oppressive.
Daylight stretches from about 13 h 24 min at the start of December to 13 h 30 min by month's end. Set against the rest of the year, December is Santa Helena's 12th-clearest and 8th-windiest month. For the whole year in context, see Santa Helena's year-round climate.
- Daytime high
- 31°
- 3rd warmest
- Overnight low
- 22°
- 10th coldest
- Rainfall
- 154 mm
- 14.4 wet days
- Daylight
- 13 h 30 min
- 6:47 AM – 8:20 PM
- Cloud cover
- 59%
- 12th clearest
- Wind
- 10 km/h
- 8th windiest
- Solar energy
- 6.39 kWh/m²
- Travel score
- 4.2
- out of 10
Temperature in December
Day-to-day highs hold fairly steady near 31°C through the month.
A typical December day in Santa Helena reaches about 31°C in the afternoon and slips back to 22°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 34°C. Set against its neighbours, December runs about 1°C warmer than November and on par with January.
| 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 |
| Avg low (°C) | 21 | 21 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 | 23 | 23 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 30 | 21 |
| 2 | 30 | 21 |
| 3 | 30 | 22 |
| 4 | 30 | 22 |
| 5 | 30 | 22 |
| 6 | 30 | 22 |
| 7 | 30 | 22 |
| 8 | 30 | 22 |
| 9 | 31 | 22 |
| 10 | 31 | 22 |
| 11 | 31 | 22 |
| 12 | 31 | 22 |
| 13 | 31 | 22 |
| 14 | 31 | 22 |
| 15 | 31 | 22 |
| 16 | 31 | 22 |
| 17 | 31 | 22 |
| 18 | 31 | 22 |
| 19 | 31 | 22 |
| 20 | 31 | 22 |
| 21 | 31 | 22 |
| 22 | 31 | 22 |
| 23 | 31 | 22 |
| 24 | 31 | 22 |
| 25 | 31 | 22 |
| 26 | 31 | 23 |
| 27 | 31 | 23 |
| 28 | 31 | 23 |
| 29 | 31 | 23 |
| 30 | 31 | 23 |
| 31 | 31 | 23 |
How December really feels in Santa Helena
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.
The story in December is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Santa Helena weather by month
How December compares with the rest of the year at a glance. December is the 3rd-warmest and 2nd-wettest month here — the current month is highlighted below.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 31° / 23° | 128 | 15.2 | 13.4 | 3.9 |
| Feb | 31° / 23° | 125 | 13.8 | 12.9 | 4.0 |
| Mar | 30° / 22° | 101 | 12 | 12.2 | 4.7 |
| Apr | 28° / 19° | 106 | 8.4 | 11.4 | 6.3 |
| May | 24° / 16° | 139 | 9.1 | 10.8 | 7.1 |
| Jun | 23° / 15° | 114 | 8.8 | 10.5 | 7.1 |
| Jul | 23° / 14° | 99 | 7.9 | 10.6 | 7.4 |
| Aug | 25° / 15° | 85 | 6.5 | 11.1 | 7.7 |
| Sep | 27° / 17° | 133 | 9.2 | 11.8 | 6.8 |
| Oct | 29° / 20° | 162 | 12.6 | 12.6 | 5.3 |
| Nov | 30° / 21° | 133 | 11.6 | 13.2 | 4.9 |
| Dec | 31° / 22° | 154 | 14.4 | 13.5 | 4.2 |
Cloud cover in December
The sky is clear or mostly clear about 34% of the time in December, the cloudiest month of the year.
Beyond those clear spells, partly cloudy skies cover about 16% of December, with mostly cloudy or overcast conditions the remaining 51%.
| 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 48 | 48 | 47 | 47 | 46 | 46 | 47 | 47 | 47 | 47 | 49 | 49 | 50 | 51 | 51 | 52 | 52 | 52 | 52 | 52 | 52 | 52 | 51 | 51 | 50 | 50 | 50 | 49 | 49 | 49 | 50 |
| Cloudier (%) | 52 | 52 | 53 | 53 | 54 | 54 | 53 | 53 | 53 | 53 | 51 | 51 | 50 | 49 | 49 | 48 | 48 | 48 | 48 | 48 | 48 | 48 | 49 | 49 | 50 | 50 | 50 | 51 | 51 | 51 | 50 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 48 | 52 |
| 2 | 48 | 52 |
| 3 | 47 | 53 |
| 4 | 47 | 53 |
| 5 | 46 | 54 |
| 6 | 46 | 54 |
| 7 | 47 | 53 |
| 8 | 47 | 53 |
| 9 | 47 | 53 |
| 10 | 47 | 53 |
| 11 | 49 | 51 |
| 12 | 49 | 51 |
| 13 | 50 | 50 |
| 14 | 51 | 49 |
| 15 | 51 | 49 |
| 16 | 52 | 48 |
| 17 | 52 | 48 |
| 18 | 52 | 48 |
| 19 | 52 | 48 |
| 20 | 52 | 48 |
| 21 | 52 | 48 |
| 22 | 52 | 48 |
| 23 | 51 | 49 |
| 24 | 51 | 49 |
| 25 | 50 | 50 |
| 26 | 50 | 50 |
| 27 | 50 | 50 |
| 28 | 49 | 51 |
| 29 | 49 | 51 |
| 30 | 49 | 51 |
| 31 | 50 | 50 |
Chance of precipitation in December
Santa Helena gets around 154 mm of rain over 14.4 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 46% and peaks near 52% on the wettest days. The odds climb toward the end of the month.
| 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 41 | 41 | 42 | 42 | 42 | 42 | 42 | 42 | 42 | 42 | 43 | 43 | 43 | 43 | 44 | 44 | 45 | 45 | 46 | 47 | 48 | 49 | 50 | 50 | 51 | 51 | 52 | 51 | 51 | 51 | 51 |
| Rain chance (%) | |
|---|---|
| 1 | 41 |
| 2 | 41 |
| 3 | 42 |
| 4 | 42 |
| 5 | 42 |
| 6 | 42 |
| 7 | 42 |
| 8 | 42 |
| 9 | 42 |
| 10 | 42 |
| 11 | 43 |
| 12 | 43 |
| 13 | 43 |
| 14 | 43 |
| 15 | 44 |
| 16 | 44 |
| 17 | 45 |
| 18 | 45 |
| 19 | 46 |
| 20 | 47 |
| 21 | 48 |
| 22 | 49 |
| 23 | 50 |
| 24 | 50 |
| 25 | 51 |
| 26 | 51 |
| 27 | 52 |
| 28 | 51 |
| 29 | 51 |
| 30 | 51 |
| 31 | 51 |
Humidity in December
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 48% of days. Sticky, muggy-or-worse air turns up on roughly 85% 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Comfortable (%) | 5 | 5 | 5 | 5 | 5 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 4 | 3 | 3 | 3 | 3 | 2 | 2 | 2 | 2 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Humid (%) | 17 | 16 | 15 | 14 | 13 | 13 | 13 | 12 | 12 | 12 | 12 | 12 | 12 | 13 | 13 | 13 | 13 | 13 | 13 | 12 | 12 | 11 | 11 | 10 | 10 | 9 | 9 | 8 | 8 | 7 | 7 |
| Muggy (%) | 43 | 43 | 43 | 43 | 43 | 43 | 42 | 42 | 41 | 41 | 40 | 39 | 39 | 38 | 37 | 37 | 36 | 35 | 35 | 34 | 33 | 32 | 31 | 30 | 30 | 29 | 29 | 28 | 28 | 28 | 28 |
| Oppressive (%) | 33 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 41 | 42 | 43 | 44 | 45 | 46 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 54 | 55 | 57 | 58 | 60 | 59 | 61 | 61 | 62 | 62 |
| Miserable (%) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 2 | 2 | 2 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| 1 | 1 | 5 | 17 | 43 | 33 | 0 |
| 2 | 1 | 5 | 16 | 43 | 35 | 0 |
| 3 | 1 | 5 | 15 | 43 | 36 | 0 |
| 4 | 1 | 5 | 14 | 43 | 37 | 0 |
| 5 | 1 | 5 | 13 | 43 | 38 | 0 |
| 6 | 1 | 4 | 13 | 43 | 39 | 0 |
| 7 | 1 | 4 | 13 | 42 | 40 | 0 |
| 8 | 1 | 4 | 12 | 42 | 41 | 0 |
| 9 | 1 | 4 | 12 | 41 | 41 | 0 |
| 10 | 1 | 4 | 12 | 41 | 42 | 0 |
| 11 | 1 | 4 | 12 | 40 | 43 | 0 |
| 12 | 1 | 4 | 12 | 39 | 44 | 0 |
| 13 | 0 | 4 | 12 | 39 | 45 | 0 |
| 14 | 0 | 4 | 13 | 38 | 46 | 0 |
| 15 | 0 | 3 | 13 | 37 | 46 | 0 |
| 16 | 0 | 3 | 13 | 37 | 47 | 0 |
| 17 | 0 | 3 | 13 | 36 | 48 | 0 |
| 18 | 0 | 3 | 13 | 35 | 49 | 0 |
| 19 | 0 | 2 | 13 | 35 | 50 | 1 |
| 20 | 0 | 2 | 12 | 34 | 51 | 1 |
| 21 | 0 | 2 | 12 | 33 | 52 | 1 |
| 22 | 0 | 2 | 11 | 32 | 54 | 1 |
| 23 | 0 | 2 | 11 | 31 | 55 | 1 |
| 24 | 0 | 2 | 10 | 30 | 57 | 1 |
| 25 | 0 | 1 | 10 | 30 | 58 | 1 |
| 26 | 0 | 1 | 9 | 29 | 60 | 1 |
| 27 | 0 | 1 | 9 | 29 | 59 | 2 |
| 28 | 0 | 1 | 8 | 28 | 61 | 2 |
| 29 | 0 | 1 | 8 | 28 | 61 | 2 |
| 30 | 0 | 1 | 7 | 28 | 62 | 2 |
| 31 | 0 | 1 | 7 | 28 | 62 | 2 |
Wind in December
Winds average 10 km/h in December.
Across December, daily wind ranges from about 10 km/h on the calmest days to 10 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 |
| 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 | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| 1 | 10 | calm |
| 2 | 10 | calm |
| 3 | 10 | calm |
| 4 | 10 | 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 | 10 | calm |
| 15 | 10 | calm |
| 16 | 10 | calm |
| 17 | 10 | calm |
| 18 | 10 | calm |
| 19 | 10 | calm |
| 20 | 10 | calm |
| 21 | 10 | calm |
| 22 | 10 | calm |
| 23 | 10 | calm |
| 24 | 10 | calm |
| 25 | 10 | calm |
| 26 | 10 | calm |
| 27 | 10 | calm |
| 28 | 10 | calm |
| 29 | 10 | calm |
| 30 | 10 | calm |
| 31 | 10 | calm |
Sunrise & sunset in December
Daylight runs from about 13 h 24 min at the start of December to 13 h 30 min by month's end. The lit band spans sunrise to sunset each day.
Days grow by about 6 minutes over December. Sunrise moves from 6:44 AM to 6:55 AM, and sunset from 8:10 PM to 8:26 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 13.4 | 13.4 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 | 13.5 |
| Sunrise (AM) | 6:44 | 6:44 | 6:44 | 6:44 | 6:45 | 6:45 | 6:45 | 6:45 | 6:45 | 6:46 | 6:46 | 6:46 | 6:46 | 6:47 | 6:47 | 6:47 | 6:48 | 6:48 | 6:49 | 6:49 | 6:49 | 6:50 | 6:50 | 6:51 | 6:51 | 6:52 | 6:52 | 6:53 | 6:54 | 6:54 | 6:55 |
| Sunset (PM) | 8:10 | 8:11 | 8:11 | 8:12 | 8:13 | 8:13 | 8:14 | 8:15 | 8:15 | 8:16 | 8:17 | 8:17 | 8:18 | 8:18 | 8:19 | 8:20 | 8:20 | 8:21 | 8:21 | 8:22 | 8:22 | 8:23 | 8:23 | 8:24 | 8:24 | 8:24 | 8:25 | 8:25 | 8:26 | 8:26 | 8:26 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 13.4 | 6:44 | 8:10 |
| 2 | 13.4 | 6:44 | 8:11 |
| 3 | 13.5 | 6:44 | 8:11 |
| 4 | 13.5 | 6:44 | 8:12 |
| 5 | 13.5 | 6:45 | 8:13 |
| 6 | 13.5 | 6:45 | 8:13 |
| 7 | 13.5 | 6:45 | 8:14 |
| 8 | 13.5 | 6:45 | 8:15 |
| 9 | 13.5 | 6:45 | 8:15 |
| 10 | 13.5 | 6:46 | 8:16 |
| 11 | 13.5 | 6:46 | 8:17 |
| 12 | 13.5 | 6:46 | 8:17 |
| 13 | 13.5 | 6:46 | 8:18 |
| 14 | 13.5 | 6:47 | 8:18 |
| 15 | 13.5 | 6:47 | 8:19 |
| 16 | 13.5 | 6:47 | 8:20 |
| 17 | 13.5 | 6:48 | 8:20 |
| 18 | 13.5 | 6:48 | 8:21 |
| 19 | 13.5 | 6:49 | 8:21 |
| 20 | 13.5 | 6:49 | 8:22 |
| 21 | 13.5 | 6:49 | 8:22 |
| 22 | 13.5 | 6:50 | 8:23 |
| 23 | 13.5 | 6:50 | 8:23 |
| 24 | 13.5 | 6:51 | 8:24 |
| 25 | 13.5 | 6:51 | 8:24 |
| 26 | 13.5 | 6:52 | 8:24 |
| 27 | 13.5 | 6:52 | 8:25 |
| 28 | 13.5 | 6:53 | 8:25 |
| 29 | 13.5 | 6:54 | 8:26 |
| 30 | 13.5 | 6:54 | 8:26 |
| 31 | 13.5 | 6:55 | 8:26 |
Solar energy in December
Average shortwave solar energy reaching the ground each day in December, about 6.39 kWh/m² — the sunniest month for solar.
For context, solar energy here swings from a low near 2.97 kWh/m² to a high of 6.39 kWh/m² in December across the year — December's 6.39 kWh/m² sits near the top of that range.
| 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 6.4 | 6.4 | 6.4 | 6.3 | 6.3 | 6.3 | 6.3 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.5 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 | 6.4 |
| Level | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 6.4 | Intense |
| 2 | 6.4 | Intense |
| 3 | 6.4 | Intense |
| 4 | 6.3 | Intense |
| 5 | 6.3 | Intense |
| 6 | 6.3 | Intense |
| 7 | 6.3 | Intense |
| 8 | 6.4 | Intense |
| 9 | 6.4 | Intense |
| 10 | 6.4 | Intense |
| 11 | 6.4 | Intense |
| 12 | 6.4 | Intense |
| 13 | 6.4 | Intense |
| 14 | 6.4 | Intense |
| 15 | 6.4 | Intense |
| 16 | 6.4 | Intense |
| 17 | 6.5 | Intense |
| 18 | 6.5 | Intense |
| 19 | 6.5 | Intense |
| 20 | 6.5 | Intense |
| 21 | 6.5 | Intense |
| 22 | 6.5 | Intense |
| 23 | 6.5 | Intense |
| 24 | 6.5 | Intense |
| 25 | 6.4 | Intense |
| 26 | 6.4 | Intense |
| 27 | 6.4 | Intense |
| 28 | 6.4 | Intense |
| 29 | 6.4 | Intense |
| 30 | 6.4 | Intense |
| 31 | 6.4 | Intense |
Is December a good time to visit Santa Helena?
Our two travel scores rate December for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
December is a reasonable time to visit Santa Helena for sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Santa Helena in December
From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In December, Santa Helena sees daytime highs around 31°C and nights near 22°C. Pack light clothes, rain gear and sun protection. About 14 days see rain.
UV index in Santa Helena in December
Clear-sky midday UV in December peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Santa Helena peaks around January 19 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 11 at about 5 (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) | 15 | 14 | 12 | 9 | 6 | 5 | 5 | 7 | 6 | 10 | 12 | 13 |
| Level | Extreme | Extreme | Extreme | Very high | High | High | Moderate | High | High | Very high | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 15 | Extreme |
| Feb | 14 | Extreme |
| Mar | 12 | Extreme |
| Apr | 9 | Very high |
| May | 6 | High |
| Jun | 5 | High |
| Jul | 5 | Moderate |
| Aug | 7 | High |
| Sep | 6 | High |
| Oct | 10 | Very high |
| Nov | 12 | Extreme |
| Dec | 13 | Extreme |
Air quality in Santa Helena in December
Average fine-particle pollution (PM2.5) through the year — so you can see where December falls, not just the annual average.
Air quality in Santa Helena is worst in September — around 21 µg/m³ PM2.5 (moderate), about 3.6× the cleanest month (March, 6 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) | 7 | 6 | 6 | 7 | 7 | 8 | 7 | 12 | 21 | 12 | 8 | 7 |
| Level | Good | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 7 | Good |
| Feb | 6 | Good |
| Mar | 6 | Good |
| Apr | 7 | Good |
| May | 7 | Good |
| Jun | 8 | Good |
| Jul | 7 | Good |
| Aug | 12 | Moderate |
| Sep | 21 | Moderate |
| Oct | 12 | Good |
| Nov | 8 | Good |
| Dec | 7 | Good |
Where is Santa Helena?
Santa Helena sits at 24.9°S, 54.3°W, 254 m above sea level, in Brazil. The nearest listed city is Marechal Cândido Rondon, 44 km away.
Topography around Santa Helena
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Santa Helena.
Within 3 km, the terrain around Santa Helena has only modest variations in elevation — a maximum elevation change of 72 m around an average of 238 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 259 m; within 80 km, large variations in elevation — a maximum elevation change of 674 m.
The land around Santa Helena is covered by cropland (31%), trees (30%) and water (20%) within 3 km, trees (33%), cropland (31%) and water (28%) within 16 km, and cropland (57%) and trees (28%) within 80 km.
Brazil travel facts
- Travel advisory
- Level 2
- Exercise Increased Caution
- Power plugs
- Type C / N
- 127 / 220 V · 60 Hz
- Prices
- ≈ 46% of US
- price level, 2025
- GDP per capita
- $10,713
- 2025
- Happiness
- 6.6 / 10
- World Happiness, 2025
- Safe drinking water
- 89%
- of population, 2024
- Homicide rate
- 19.3
- per 100k, 2023
- Road deaths
- 16
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Low
- EF EPI 482
- 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 Santa Helena (-24.8603°, -54.3328°, elevation 254 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. 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).