March 21 is generally a great time to visit Rio de Janeiro. While there is a slight chance of rain (35%), showers are usually brief. Expect comfortable 30°C weather. Rio de Janeiro is seeing high visitor numbers, so iconic spots may be busier than usual.
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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 March 21
"Warm & Sunny. Expect average highs of 29.7°C. 35% chance of rain."
What to Wear in Rio de Janeiro in March
Based on historical data for March 21, Rio de Janeiro typically experiences temperatures between 22.5°C and 29.7°C. We recommend packing t-shirt, light clothing, umbrella to stay comfortable. With a 35% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for Rio de Janeiro
Smart Suitcase
- T-Shirt
- Light Clothing
- Umbrella
Average High
29.7°C
Daytime Peak
Average Low
22.5°C
Nighttime Low
Feels Like
36.8°C
🔥 Heat index effect
Rain Chance
35%
Avg 2.7mm if it rains
Cloud Cover
60%
Light drizzle
Pressure
1014.1 hPa
Low volatility
Rio de Janeiro Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
✓ This date historically delivers consistent weather 78% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
05:00 - 10:00
16:00 - 18:00
Type I-II
🔴 25 min to burn
Type III-IV
🟡 38 min to burn
Type V-VI
🟢 63 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
25.9°C
Humid/Sticky
Heat Index
36.8°C
Feels hotter
😕 Best outdoor time:
Morning hours (before 11 AM)
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
✅ Excellent Swimming Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Brazil
Flight Traffic
Busy
68/100 pressure index
Health Advisory
Required
2 vaccines • View Details →
Landing Slots
~171
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Rio de Janeiro
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
05:57
☀️ Noon
12:01
🌇 Sunset
18:04
⏱️ Daylight
12h 6m
Wind Speed
14.6 km/h
Gentle breeze
Sunshine
9.7 hrs
Direct Sun (Cloud-free)
Humidity
80%
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
⛅ Good
Tourist Crowds
🟢 Moderate
Price Level
💰💰 Moderate
Health & Wellbeing
Meteo-Health Forecast
Stable conditions. Low risk of headaches.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is acceptable. Sensitive individuals should limit prolonged outdoor exertion.
Regional Safety Profile
Seismic Activity
Zero seismic activity detected in 30 years.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Rio de Janeiro on March 21 averages 29.7°C with a 35% precipitation probability. Wedding/Outdoor Event Score: 87/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Rio de Janeiro Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
March 23
29.5°C • 26% rain
Score
92
March 24
29.4°C • 25% rain
Score
92
March 25
29.4°C • 27% rain
Score
91
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (March 21) in other destinations
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📍 Is Rio de Janeiro Worth Visiting on March 21?
Planning a trip to Rio de Janeiro on March 21? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 29.7°C with a 35% historical precipitation risk.
✈️ Travel Logistics: Approximately 171 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 26°C (tropical bath). Wave conditions are generally fun waves with heights around 0.88m.
📊 Historical Extremes: The hottest March 21 recorded in the last 30 years saw temperatures hit 37.5°C in 2024, while the coldest dropped to 20.6°C in 2022.