May 4 is generally a great time to visit San Juan. While there is a slight chance of rain (30%), showers are usually brief. Expect comfortable 30°C weather. As it's peak season for San Juan, we recommend booking your stay well in advance to secure the best rates.
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Essential Travel Info for San Juan
Currency
USD
$ United States dollar
Language
English
+1 more
Driving
Right side
San Juan Weather Forecast for May 4
"Warm & Sunny. Expect average highs of 30°C. 30% chance of rain."
What to Wear in San Juan in May
Based on historical data for May 4, San Juan typically experiences temperatures between 23.1°C and 30°C. We recommend packing t-shirt, light clothing to stay comfortable. With a 30% chance of rain, keeping a raincoat or umbrella handy is a smart move.
Complete Packing Guide
Weekly breakdown & essential items for San Juan
Smart Suitcase
- T-Shirt
- Light Clothing
Average High
30°C
Daytime Peak
Average Low
23.1°C
Nighttime Low
Feels Like
36.8°C
🔥 Heat index effect
Rain Chance
30%
Avg 2.1mm if it rains
Cloud Cover
51%
Light drizzle
Pressure
1015.2 hPa
Low volatility
San Juan Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
✓ This date historically delivers consistent weather 76% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30+ required, seek shade
05:00 - 10:00
16:00 - 18:00
Type I-II
🔴 12 min to burn
Type III-IV
🟡 18 min to burn
Type V-VI
🟢 30 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
25.5°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
⚠️ Mixed Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Puerto Rico
Flight Traffic
High
94/100 pressure index
Health Advisory
Required
2 vaccines • View Details →
Landing Slots
~203
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in San Juan
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
05:56
☀️ Noon
12:22
🌇 Sunset
18:48
⏱️ Daylight
12h 51m
Wind Speed
20.2 km/h
Moderate wind
Sunshine
11.4 hrs
Direct Sun (Cloud-free)
Humidity
77%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for San Juan
Smart Flight Estimator
Airport-to-Airport Logistics
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Travel Health & Safety in San Juan
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Stable conditions. Low risk of headaches.
Weather unlikely to affect joint pain.
Moderate fish activity expected.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Moderate seismic activity. Occasional tremors possible.
Atlantic Hurricane Risk
Season: Jun - Nov
"According to 30YearWeather's analysis of 30 years of NASA satellite data, San Juan on May 4 averages 30°C with a 30% precipitation probability. Wedding/Outdoor Event Score: 91/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
San Juan Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Compare Other Cities
Same date (May 4) in other destinations
🌍 Explore the same date in different destinations around the world
📍 Is San Juan Worth Visiting on May 4?
Planning a trip to San Juan on May 4? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year typically offers vibrant summer conditions averaging 30°C with a 30% historical precipitation risk.
✈️ Travel Logistics: Approximately 203 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 7 vaccinations are recommended for Puerto Rico, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 27.7°C (tropical bath). Wave conditions are generally fun waves with heights around 1.16m.
📊 Historical Extremes: The hottest May 4 recorded in the last 30 years saw temperatures hit 34.3°C in 2023, while the coldest dropped to 22.4°C in 2018.