30YearWeather
Rio de Janeiro, August 18
Rio de Janeiro street view during August
Historical Weather Analysis

Rio de Janeiro Weather on August 18 — Best Time to Visit?

Based on 30 years of historical data, we have the answer.

clear-day

26.7°C

High

17°C

Low

15%

Rain

☀️ Feels like 27.8°C (humidity)

partly-cloudy-day
YES, GOOD CHOICE

August 18 is generally a great time to visit Rio de Janeiro. While there is a slight chance of rain (15%), showers are usually brief. Expect comfortable 27°C weather. It's a lively time to explore Rio de Janeiro, with most attractions operating at full capacity.

Essential Travel Info for Rio de Janeiro

Currency

BRL

R$ Brazilian real

Language

Portuguese

Driving

Right side

Safety

Moderate Safety

GPI: 2.465

Rio de Janeiro Weather Forecast for August 18

"Warm & Sunny. Expect average highs of 26.7°C. 15% chance of rain."

What to Wear in Rio de Janeiro in August

Based on historical data for August 18, Rio de Janeiro typically experiences temperatures between 17°C and 26.7°C. We recommend packing t-shirt, light clothing to stay comfortable. Trends suggest it will stay mostly dry (15% rain probability), but checking the forecast before heading out is always wise.

Complete Packing Guide

Weekly breakdown & essential items for Rio de Janeiro

View Guide

Smart Suitcase

  • T-Shirt
  • Light Clothing

Average High

extreme-hot

26.7°C

Daytime Peak

Average Low

extreme-cold

17°C

Nighttime Low

Feels Like

partly-cloudy-day

27.8°C

☀️ Minor difference

Rain Chance

rain

15%

Avg 0.5mm if it rains

Cloud Cover

cloudy

39%

Overcast

Pressure

pressure

1019.3 hPa

Medium volatility

Rio de Janeiro Weather Conditions & UV Index

Weather Confidence

30-year variance analysis

87%Highly Predictable

Based on 10 years of data

Temperature
±3.5°CModerate
Precipitation
8-40%Moderate

🎯 This date historically delivers consistent weather 87% of the time. Safe to plan outdoor activities with confidence.

Sun Exposure

UV Index & Safety Guide

2Low
036811+

Protection Needed

SPF 15 for extended outdoor time

Time to Sunburn

Type I-II

🔴 40 min to burn

Type III-IV

🟡 60 min to burn

Type V-VI

🟢 100 min to burn

UV estimate based on latitude, season & cloud cover. Actual UV may vary.

Outdoor Comfort

How pleasant is it outside?

62Moderate
TemperatureHot
HumidityMuggy
WindBreezy

Dew Point

21.9°C

Humid/Sticky

Heat Stress

Low

No heat warning

😐 Best outdoor time:
Morning hours (before 11 AM)

Marine Conditions

Water Temp
22.1°C
🏊 Swimming Pool
Avg daily surface temperature
Surf Conditions
1.01m
🌊 Fun Waves
Max daily wave height
Advisories

Marine Life

No special warnings. Enjoy the swim!

Swim Index

⚠️ Mixed Conditions

Travel & Logistics Insights

Local Calendar

Business Day

Standard hours in Brazil

Flight Traffic

Busy

63/100 pressure index

Health Advisory

Required

2 vaccines • View Details →

Landing Slots

~157

Daily arrival options (inc. codeshare)

Sunrise, Sunset & Wind in Rio de Janeiro

Daylight & Sun

Solar Elevation Cycle

🌅 Sunrise

06:16

☀️ Noon

11:58

🌇 Sunset

17:39

⏱️ Daylight

11h 22m

Golden Hour
Morning06:16 - 06:47
17:08 - 17:39Evening

Wind Speed

wind

16.6 km/h

Gentle breeze

Sunshine

clear-day

9.0 hrs

Direct Sun (Cloud-free)

Humidity

humidity

75%

Humid / Damp

Travel Intelligence

Exclusive flight analytics & health data for Rio de Janeiro

Smart Flight Estimator

Airport-to-Airport Logistics

unlock smart flight estimates

Add your home location in settings to see airport details.

Travel Health & Safety in Rio de Janeiro

Travel Comfort Index

Real-time tourism conditions

Weather Quality

☀️ Excellent

88/100

Tourist Crowds

🔴 Very Busy

100/100

Price Level

💰💰💰 Expensive

100/100

Health & Wellbeing

Meteo-Health Forecast

85Score
Atmospheric Pressure1019.3 hPa
Volatility:Medium
Migraine RiskMedium

Moderate fluctuations. Some sensitivity possible.

Joint Pain RiskLow

Weather unlikely to affect joint pain.

Fishing IndexFair

Moderate fish activity expected.

Air Quality Forecast
79AQI
Moderate
PM2.5 Concentration15.8 µg/m³

Air quality is acceptable. Sensitive individuals should limit prolonged outdoor exertion.

Regional Safety Profile

Stable

Seismic Activity

Zero seismic activity detected in 30 years.

Total events (30y):0
💡 No earthquake preparedness needed. Enjoy your stay!
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Rio de Janeiro on August 18 averages 26.7°C with a 15% precipitation probability. Wedding/Outdoor Event Score: 100/100."

— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology

Rio de Janeiro Weather History (2010–2024)

Temperature History

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Hall of Fame

Records from last 10 years

Hottest
2023
31.7°C
Coldest
2019
15.3°C
Rainiest
2017
7.7mm

Compare Other Cities

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📍 Is Rio de Janeiro Worth Visiting on August 18?

Planning a trip to Rio de Janeiro on August 18? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 26.7°C with a 15% historical precipitation risk.

✈️ Travel Logistics: Approximately 157 landing slots available daily during this period, indicating manageable crowd levels.

💉 Health Advisory: 9 vaccinations are recommended for Brazil, including COVID-19.

🌊 Coastal Conditions: Water temperature averages 22.1°C (swimming pool). Wave conditions are generally fun waves with heights around 1.01m.

📊 Historical Extremes: The hottest August 18 recorded in the last 30 years saw temperatures hit 31.7°C in 2023, while the coldest dropped to 15.3°C in 2019.

Rio de Janeiro Weather FAQ