Rio das Ostras weather in December
In December, Rio das Ostras sees average daytime highs of 29°C and overnight lows near 23°C, with 222 mm of rain across 19 wet days and about 13.4 hours of daylight. It is the 4th-warmest and 1st-wettest month of the year here.
Highs climb over the month, from about 28°C in the first days to 30°C by the end. The sky is clear or mostly clear about 17% of the time in December, and the air most often feels oppressive.
Daylight stretches from about 13 h 18 min at the start of December to 13 h 24 min by month's end. Set against the rest of the year, December is Rio das Ostras's 11th-clearest and 7th-windiest month. For the whole year in context, see Rio das Ostras's year-round climate.
- Daytime high
- 29°
- 4th warmest
- Overnight low
- 23°
- 9th coldest
- Rainfall
- 222 mm
- 19 wet days
- Daylight
- 13 h 24 min
- 6:03 AM – 7:25 PM
- Cloud cover
- 71%
- 11th clearest
- Wind
- 10 km/h
- 7th windiest
- Solar energy
- 6.02 kWh/m²
- Travel score
- 4.2
- out of 10
Rio das Ostras is human settlement in Brazil.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in December
Highs climb over the month, from about 28°C in the first days to 30°C by the end.
A typical December day in Rio das Ostras reaches about 29°C in the afternoon and slips back to 23°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 33°C. Set against its neighbours, December runs about 2°C warmer than November and about 1°C cooler than 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) | 28 | 28 | 28 | 28 | 28 | 28 | 28 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 29 | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 30 | 30 |
| Avg low (°C) | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 | 23 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| 1 | 28 | 22 |
| 2 | 28 | 22 |
| 3 | 28 | 22 |
| 4 | 28 | 22 |
| 5 | 28 | 22 |
| 6 | 28 | 22 |
| 7 | 28 | 22 |
| 8 | 29 | 22 |
| 9 | 29 | 22 |
| 10 | 29 | 22 |
| 11 | 29 | 23 |
| 12 | 29 | 23 |
| 13 | 29 | 23 |
| 14 | 29 | 23 |
| 15 | 29 | 23 |
| 16 | 29 | 23 |
| 17 | 29 | 23 |
| 18 | 29 | 23 |
| 19 | 29 | 23 |
| 20 | 29 | 23 |
| 21 | 29 | 23 |
| 22 | 30 | 23 |
| 23 | 30 | 23 |
| 24 | 30 | 23 |
| 25 | 30 | 23 |
| 26 | 30 | 23 |
| 27 | 30 | 23 |
| 28 | 30 | 23 |
| 29 | 30 | 23 |
| 30 | 30 | 23 |
| 31 | 30 | 23 |
How December really feels in Rio das Ostras
Once humidity and wind are folded in, December averages 18 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.
Rio das Ostras weather by month
How December compares with the rest of the year at a glance. December is the 4th-warmest and 1st-wettest month here — the current month is highlighted below.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 30° / 23° | 206 | 16.6 | 13.2 | 4.1 |
| Feb | 31° / 24° | 136 | 12.7 | 12.8 | 4.2 |
| Mar | 30° / 23° | 172 | 17.8 | 12.2 | 4.3 |
| Apr | 28° / 21° | 85 | 12 | 11.5 | 5.7 |
| May | 26° / 19° | 60 | 9.5 | 10.9 | 6.9 |
| Jun | 26° / 18° | 31 | 5.9 | 10.6 | 7.6 |
| Jul | 25° / 18° | 29 | 5.6 | 10.8 | 7.8 |
| Aug | 26° / 18° | 34 | 6.3 | 11.2 | 7.6 |
| Sep | 26° / 19° | 73 | 10.1 | 11.9 | 6.7 |
| Oct | 27° / 20° | 108 | 12 | 12.5 | 6.1 |
| Nov | 27° / 21° | 203 | 17.5 | 13.1 | 5.1 |
| Dec | 29° / 23° | 222 | 19 | 13.4 | 4.2 |
Cloud cover in December
The sky is clear or mostly clear about 17% of the time in December.
Beyond those clear spells, partly cloudy skies cover about 14% of December, with mostly cloudy or overcast conditions the remaining 68%. Skies tend to open up as the month goes on.
| 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 (%) | 30 | 29 | 28 | 28 | 28 | 28 | 27 | 27 | 27 | 28 | 28 | 28 | 30 | 31 | 32 | 32 | 33 | 33 | 35 | 35 | 36 | 35 | 36 | 36 | 36 | 34 | 34 | 34 | 34 | 34 | 34 |
| Cloudier (%) | 70 | 71 | 72 | 72 | 72 | 72 | 73 | 73 | 73 | 72 | 72 | 72 | 70 | 69 | 68 | 68 | 67 | 67 | 65 | 65 | 64 | 65 | 64 | 64 | 64 | 66 | 66 | 66 | 66 | 66 | 66 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 30 | 70 |
| 2 | 29 | 71 |
| 3 | 28 | 72 |
| 4 | 28 | 72 |
| 5 | 28 | 72 |
| 6 | 28 | 72 |
| 7 | 27 | 73 |
| 8 | 27 | 73 |
| 9 | 27 | 73 |
| 10 | 28 | 72 |
| 11 | 28 | 72 |
| 12 | 28 | 72 |
| 13 | 30 | 70 |
| 14 | 31 | 69 |
| 15 | 32 | 68 |
| 16 | 32 | 68 |
| 17 | 33 | 67 |
| 18 | 33 | 67 |
| 19 | 35 | 65 |
| 20 | 35 | 65 |
| 21 | 36 | 64 |
| 22 | 35 | 65 |
| 23 | 36 | 64 |
| 24 | 36 | 64 |
| 25 | 36 | 64 |
| 26 | 34 | 66 |
| 27 | 34 | 66 |
| 28 | 34 | 66 |
| 29 | 34 | 66 |
| 30 | 34 | 66 |
| 31 | 34 | 66 |
Chance of precipitation in December
Rio das Ostras gets around 222 mm of rain over 19 wet days in December, the wettest month. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 61% and peaks near 62% 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 59 | 60 | 60 | 60 | 61 | 61 | 61 | 61 | 62 | 62 | 62 | 62 | 62 | 62 | 61 | 61 | 61 | 61 | 61 | 61 | 61 | 61 | 61 | 61 | 62 | 62 | 62 | 62 | 62 | 62 | 61 |
| Rain chance (%) | |
|---|---|
| 1 | 59 |
| 2 | 60 |
| 3 | 60 |
| 4 | 60 |
| 5 | 61 |
| 6 | 61 |
| 7 | 61 |
| 8 | 61 |
| 9 | 62 |
| 10 | 62 |
| 11 | 62 |
| 12 | 62 |
| 13 | 62 |
| 14 | 62 |
| 15 | 61 |
| 16 | 61 |
| 17 | 61 |
| 18 | 61 |
| 19 | 61 |
| 20 | 61 |
| 21 | 61 |
| 22 | 61 |
| 23 | 61 |
| 24 | 61 |
| 25 | 62 |
| 26 | 62 |
| 27 | 62 |
| 28 | 62 |
| 29 | 62 |
| 30 | 62 |
| 31 | 61 |
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 68% of days. Sticky, muggy-or-worse air turns up on roughly 97% 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 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Humid (%) | 8 | 8 | 7 | 7 | 7 | 6 | 6 | 5 | 5 | 4 | 4 | 3 | 3 | 3 | 2 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Muggy (%) | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 17 | 16 | 15 | 14 | 13 | 12 | 12 | 11 | 11 | 10 | 10 | 10 | 10 | 11 | 11 |
| Oppressive (%) | 57 | 58 | 59 | 60 | 60 | 62 | 62 | 64 | 65 | 65 | 66 | 67 | 68 | 68 | 70 | 70 | 70 | 72 | 72 | 73 | 73 | 74 | 73 | 74 | 73 | 73 | 73 | 72 | 72 | 71 | 71 |
| Miserable (%) | 4 | 4 | 5 | 5 | 6 | 6 | 7 | 7 | 7 | 8 | 8 | 9 | 9 | 10 | 10 | 11 | 11 | 11 | 12 | 12 | 13 | 13 | 14 | 14 | 15 | 16 | 16 | 17 | 17 | 17 | 17 |
| Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|
| 1 | 8 | 31 | 57 | 4 |
| 2 | 8 | 30 | 58 | 4 |
| 3 | 7 | 29 | 59 | 5 |
| 4 | 7 | 28 | 60 | 5 |
| 5 | 7 | 27 | 60 | 6 |
| 6 | 6 | 26 | 62 | 6 |
| 7 | 6 | 25 | 62 | 7 |
| 8 | 5 | 24 | 64 | 7 |
| 9 | 5 | 23 | 65 | 7 |
| 10 | 4 | 23 | 65 | 8 |
| 11 | 4 | 22 | 66 | 8 |
| 12 | 3 | 21 | 67 | 9 |
| 13 | 3 | 20 | 68 | 9 |
| 14 | 3 | 19 | 68 | 10 |
| 15 | 2 | 18 | 70 | 10 |
| 16 | 2 | 17 | 70 | 11 |
| 17 | 2 | 17 | 70 | 11 |
| 18 | 1 | 16 | 72 | 11 |
| 19 | 1 | 15 | 72 | 12 |
| 20 | 1 | 14 | 73 | 12 |
| 21 | 1 | 13 | 73 | 13 |
| 22 | 1 | 12 | 74 | 13 |
| 23 | 1 | 12 | 73 | 14 |
| 24 | 1 | 11 | 74 | 14 |
| 25 | 1 | 11 | 73 | 15 |
| 26 | 1 | 10 | 73 | 16 |
| 27 | 1 | 10 | 73 | 16 |
| 28 | 1 | 10 | 72 | 17 |
| 29 | 1 | 10 | 72 | 17 |
| 30 | 1 | 11 | 71 | 17 |
| 31 | 1 | 11 | 71 | 17 |
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 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 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 11 | 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 | 11 | calm |
| 2 | 11 | calm |
| 3 | 11 | calm |
| 4 | 11 | calm |
| 5 | 11 | calm |
| 6 | 11 | calm |
| 7 | 11 | calm |
| 8 | 11 | calm |
| 9 | 11 | calm |
| 10 | 11 | calm |
| 11 | 11 | calm |
| 12 | 11 | 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 18 min at the start of December to 13 h 24 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 5:59 AM to 6:10 AM, and sunset from 7:16 PM to 7:32 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) | 13.3 | 13.3 | 13.3 | 13.3 | 13.3 | 13.3 | 13.3 | 13.3 | 13.3 | 13.3 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 | 13.4 |
| Sunrise (AM) | 5:59 | 5:59 | 5:59 | 5:59 | 6:00 | 6:00 | 6:00 | 6:00 | 6:01 | 6:01 | 6:01 | 6:01 | 6:02 | 6:02 | 6:02 | 6:03 | 6:03 | 6:04 | 6:04 | 6:04 | 6:05 | 6:05 | 6:06 | 6:06 | 6:07 | 6:07 | 6:08 | 6:08 | 6:09 | 6:09 | 6:10 |
| Sunset (PM) | 7:16 | 7:17 | 7:17 | 7:18 | 7:19 | 7:19 | 7:20 | 7:20 | 7:21 | 7:22 | 7:22 | 7:23 | 7:23 | 7:24 | 7:25 | 7:25 | 7:26 | 7:26 | 7:27 | 7:27 | 7:28 | 7:28 | 7:29 | 7:29 | 7:30 | 7:30 | 7:30 | 7:31 | 7:31 | 7:31 | 7:32 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 13.3 | 5:59 | 7:16 |
| 2 | 13.3 | 5:59 | 7:17 |
| 3 | 13.3 | 5:59 | 7:17 |
| 4 | 13.3 | 5:59 | 7:18 |
| 5 | 13.3 | 6:00 | 7:19 |
| 6 | 13.3 | 6:00 | 7:19 |
| 7 | 13.3 | 6:00 | 7:20 |
| 8 | 13.3 | 6:00 | 7:20 |
| 9 | 13.3 | 6:01 | 7:21 |
| 10 | 13.3 | 6:01 | 7:22 |
| 11 | 13.4 | 6:01 | 7:22 |
| 12 | 13.4 | 6:01 | 7:23 |
| 13 | 13.4 | 6:02 | 7:23 |
| 14 | 13.4 | 6:02 | 7:24 |
| 15 | 13.4 | 6:02 | 7:25 |
| 16 | 13.4 | 6:03 | 7:25 |
| 17 | 13.4 | 6:03 | 7:26 |
| 18 | 13.4 | 6:04 | 7:26 |
| 19 | 13.4 | 6:04 | 7:27 |
| 20 | 13.4 | 6:04 | 7:27 |
| 21 | 13.4 | 6:05 | 7:28 |
| 22 | 13.4 | 6:05 | 7:28 |
| 23 | 13.4 | 6:06 | 7:29 |
| 24 | 13.4 | 6:06 | 7:29 |
| 25 | 13.4 | 6:07 | 7:30 |
| 26 | 13.4 | 6:07 | 7:30 |
| 27 | 13.4 | 6:08 | 7:30 |
| 28 | 13.4 | 6:08 | 7:31 |
| 29 | 13.4 | 6:09 | 7:31 |
| 30 | 13.4 | 6:09 | 7:31 |
| 31 | 13.4 | 6:10 | 7:32 |
Solar energy in December
Average shortwave solar energy reaching the ground each day in December, about 6.02 kWh/m².
For context, solar energy here swings from a low near 3.54 kWh/m² to a high of 6.31 kWh/m² in February across the year — December's 6.02 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) | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 | 5.9 | 5.9 | 5.9 | 5.9 | 5.9 | 5.9 | 5.9 | 6.0 | 6.0 | 6.0 | 6.0 | 6.0 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.1 | 6.2 |
| Level | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 5.8 | Bright |
| 2 | 5.8 | Bright |
| 3 | 5.8 | Bright |
| 4 | 5.8 | Bright |
| 5 | 5.8 | Bright |
| 6 | 5.8 | Bright |
| 7 | 5.8 | Bright |
| 8 | 5.9 | Bright |
| 9 | 5.9 | Bright |
| 10 | 5.9 | Bright |
| 11 | 5.9 | Bright |
| 12 | 5.9 | Bright |
| 13 | 5.9 | Bright |
| 14 | 5.9 | Bright |
| 15 | 6.0 | Bright |
| 16 | 6.0 | Bright |
| 17 | 6.0 | Intense |
| 18 | 6.0 | Intense |
| 19 | 6.0 | Intense |
| 20 | 6.1 | Intense |
| 21 | 6.1 | Intense |
| 22 | 6.1 | Intense |
| 23 | 6.1 | Intense |
| 24 | 6.1 | Intense |
| 25 | 6.1 | Intense |
| 26 | 6.1 | Intense |
| 27 | 6.1 | Intense |
| 28 | 6.1 | Intense |
| 29 | 6.1 | Intense |
| 30 | 6.1 | Intense |
| 31 | 6.2 | Intense |
Hazard calendar for Rio das Ostras
In December, Rio das Ostras sits inside its rainy season season. The full year is below, with each hazard's peak months called out.
Rio das Ostras's rainy season runs October–March, when most of the year's rain falls.
Is December a good time to visit Rio das Ostras?
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 Rio das Ostras for sightseeing.
What to pack for Rio das Ostras in December
From December's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In December, Rio das Ostras sees daytime highs around 29°C and nights near 23°C. Pack light clothes, rain gear and sun protection. About 19 days see rain.
Sea temperature near Rio das Ostras in December
The nearest coast averages about 24°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 13 km away) is warmest in March at about 25°C and coldest in September near 21°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) | 24 | 24 | 25 | 25 | 24 | 23 | 22 | 22 | 21 | 22 | 22 | 24 |
| Comfort | Refreshing | Warm | Warm | Warm | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 24 | Refreshing |
| Feb | 24 | Warm |
| Mar | 25 | Warm |
| Apr | 25 | Warm |
| May | 24 | Refreshing |
| Jun | 23 | Refreshing |
| Jul | 22 | Refreshing |
| Aug | 22 | Refreshing |
| Sep | 21 | Refreshing |
| Oct | 22 | Refreshing |
| Nov | 22 | Refreshing |
| Dec | 24 | Refreshing |
UV index in Rio das Ostras in December
Clear-sky midday UV in December peaks around 14 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Rio das Ostras peaks around January 16 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 11 at about 6 (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) | 14 | 14 | 13 | 9 | 7 | 6 | 6 | 8 | 8 | 12 | 14 | 14 |
| Level | Extreme | Extreme | Extreme | Very high | High | High | High | Very high | Very high | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 14 | Extreme |
| Mar | 13 | Extreme |
| Apr | 9 | Very high |
| May | 7 | High |
| Jun | 6 | High |
| Jul | 6 | High |
| Aug | 8 | Very high |
| Sep | 8 | Very high |
| Oct | 12 | Extreme |
| Nov | 14 | Extreme |
| Dec | 14 | Extreme |
Where is Rio das Ostras?
Rio das Ostras sits at 22.5°S, 41.9°W, 11 m above sea level, in Brazil. The nearest listed city is Macaé, 23 km away.
Topography around Rio das Ostras
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Rio das Ostras.
Within 3 km, the terrain around Rio das Ostras has only modest variations in elevation — a maximum elevation change of 49 m around an average of 4 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 693 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,215 m.
The land around Rio das Ostras is covered by water (39%) and artificial surfaces (32%) within 3 km, water (45%) and grassland (27%) within 16 km, and water (37%), trees (31%) and grassland (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 Rio das Ostras (-22.5269°, -41.945°, elevation 11 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).