Climate averages 1991–2020
Rio das Ostras weather
in July.
A warm, fairly dry month: the coolest and the driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
July is a warm month in Rio das Ostras: daytime highs average 24.4°C and nights cool to about 17.4°C. By daytime temperature it is the coolest month of the year.
Expect about 29 mm of rain on roughly 6 days, which makes July a fairly dry month (the driest month of the year). Daylight, from sunrise to sunset, lasts about 10 h 53 min on an average July day.
The nearest other city in this atlas is Macaé (23 km away). In July its highs average 24.2°C, about as warm as Rio das Ostras, with 33 mm of rain.
Among the 448 cities listed in Brazil, Rio das Ostras ranks joint 231st of 448 for the warmest July highs and joint 177th of 448 for the driest July (rainfall, lowest first). The mean July high of those 448 cities is 24.7°C; Rio das Ostras is 0.3°C cooler than that mean.
From July to August, average highs rise by 0.6°C to 25.0°C, and monthly rainfall rises from 29 mm to 34 mm.
The annual picture
July in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Rio das Ostras climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 29.4°C23.2°C | 23.2°C | 206 | 16.5 | 13.313 h |
| February | 29.8°C23.4°C | 23.4°C | 141 | 12.8 | 12.913 h |
| March | 28.6°C22.8°C | 22.8°C | 172 | 17.6 | 12.212 h |
| April | 27.2°C21.3°C | 21.3°C | 85 | 12.1 | 11.612 h |
| May | 25.1°C19.1°C | 19.1°C | 60 | 9.5 | 11.111 h |
| June | 24.7°C17.9°C | 17.9°C | 31 | 5.9 | 10.811 h |
| July, selected | 24.4°C17.4°C | 17.4°C | 29 | 5.6 | 10.911 h |
| August | 25.0°C17.8°C | 17.8°C | 34 | 6.5 | 11.311 h |
| September | 25.7°C18.9°C | 18.9°C | 73 | 10.0 | 11.912 h |
| October | 26.6°C20.2°C | 20.2°C | 108 | 11.9 | 12.613 h |
| November | 26.8°C21.0°C | 21.0°C | 203 | 17.5 | 13.213 h |
| December | 28.4°C22.4°C | 22.4°C | 222 | 19.0 | 13.513 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
July in nearby cities
- Macaé in JulyBrazil · 23 kmHigh 24.2°C · Low 17.9°C · 33 mm rain
- São Pedro da Aldeia in JulyBrazil · 38 kmHigh 23.2°C · Low 18.8°C · 33 mm rain
- Cabo Frio in JulyBrazil · 41 kmHigh 23.3°C · Low 19.3°C · 35 mm rain
- Araruama in JulyBrazil · 56 kmHigh 23.2°C · Low 18.9°C · 45 mm rain
- Nova Friburgo in JulyBrazil · 66 kmHigh 21.5°C · Low 13.3°C · 42 mm rain
- Saquarema in JulyBrazil · 68 kmHigh 23.4°C · Low 18.2°C · 40 mm rain
- Itaboraí in JulyBrazil · 97 kmHigh 24.1°C · Low 15.4°C · 44 mm rain
- Maricá in JulyBrazil · 100 kmHigh 24.4°C · Low 17.9°C · 45 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Rio das Ostras) is explained once on the Rio das Ostras year overview and on the Sources, method and limits page.