September 21 is generally a great time to visit Naha. While there is a slight chance of rain (35%), showers are usually brief. Expect comfortable 29°C weather. Naha is currently in its most popular travel window, meaning vibrant crowds and premium pricing.
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Essential Travel Info for Naha
Currency
JPY
¥ Japanese yen
Language
Japanese
Driving
Left side
Safety
Very High Safety
GPI: 1.336
Naha Weather Forecast for September 21
"Warm & Sunny. Expect average highs of 28.9°C. 35% chance of rain."
What to Wear in Naha in September
Based on historical data for September 21, Naha typically experiences temperatures between 26°C and 28.9°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 Naha
Smart Suitcase
- T-Shirt
- Light Clothing
- Umbrella
Average High
28.9°C
Daytime Peak
Average Low
26°C
Nighttime Low
Feels Like
34°C
🔥 Heat index effect
Rain Chance
35%
Avg 2.8mm if it rains
Cloud Cover
51%
Light drizzle
Pressure
1009.8 hPa
Medium volatility
Naha Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
✓ Weather is generally predictable, but pack for minor variations. A light backup layer is recommended.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
06:00 - 10:00
16:00 - 18:00
Type I-II
🔴 23 min to burn
Type III-IV
🟡 35 min to burn
Type V-VI
🟢 58 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
24.7°C
Humid/Sticky
Heat Index
34°C
Feels hotter
😕 Best outdoor time:
Morning hours (before 11 AM)
Marine Conditions
Jellyfish Warning
High water temps may attract jellyfish swarms.
Swim Index
⚠️ Mixed Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in Japan
Flight Traffic
High
97/100 pressure index
Health Advisory
Required
1 vaccine • View Details →
Landing Slots
~189
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Naha
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
06:18
☀️ Noon
12:23
🌇 Sunset
18:29
⏱️ Daylight
12h 10m
Wind Speed
26.3 km/h
Moderate wind
Sunshine
10.2 hrs
Direct Sun (Cloud-free)
Humidity
78%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Naha
Smart Flight Estimator
Airport-to-Airport Logistics
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Travel Health & Safety in Naha
Travel Comfort Index
Real-time tourism conditions
Weather Quality
⛅ Good
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Moderate fluctuations. Some sensitivity possible.
Mild discomfort possible for arthritic conditions.
Moderate fish activity expected.
Air quality is excellent. Perfect for outdoor activities.
Regional Safety Profile
Seismic Activity
Active seismic zone. Multiple earthquakes per year.
Typhoon Risk
Year-round risk present
Travel Alert: This region has elevated natural risks. We recommend registering with your embassy and keeping emergency numbers handy.
"According to 30YearWeather's analysis of 30 years of NASA satellite data, Naha on September 21 averages 28.9°C with a 35% precipitation probability. Wedding/Outdoor Event Score: 83/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Naha Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
September 25
28.7°C • 30% rain
Score
89
September 23
28.7°C • 33% rain
Score
85
September 24
28.7°C • 33% rain
Score
85
💡 Moving your event by a few days could significantly improve weather conditions
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Same date (September 21) in other destinations
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🌍 Explore the same date in different destinations around the world
📍 Is Naha Worth Visiting on September 21?
Planning a trip to Naha on September 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 28.9°C with a 35% historical precipitation risk.
✈️ Travel Logistics: Approximately 189 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 8 vaccinations are recommended for Japan, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 29.8°C (hot soup). Wave conditions are generally surfers only with heights around 1.53m.
📊 Historical Extremes: The hottest September 21 recorded in the last 30 years saw temperatures hit 32.3°C in 2025, while the coldest dropped to 24.8°C in 2021.