September 17 is generally a great time to visit Cape Town. While there is a slight chance of rain (16%), showers are usually brief. Expect comfortable 18°C weather. Expect a bustling atmosphere in Cape Town right now—this is when the city truly comes alive with visitors.
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Essential Travel Info for Cape Town
Currency
ZAR
R South African rand
Language
Afrikaans
+10 more
Driving
Left side
Connect
Many carriers (especially in Europe) cha...
Safety
Moderate Safety
GPI: 2.283
Cape Town Weather Forecast for September 17
"Mild & Comfortable. Expect average highs of 18.3°C. 16% chance of rain."
What to Wear in Cape Town in September
Based on historical data for September 17, Cape Town typically experiences temperatures between 10.1°C and 18.3°C. We recommend packing light jacket, long pants to stay comfortable. Trends suggest it will stay mostly dry (16% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Cape Town
Smart Suitcase
- Light Jacket
- Long Pants
Average High
18.3°C
Daytime Peak
Average Low
10.1°C
Nighttime Low
Feels Like
18.3°C
🌤️ Feels accurate
Rain Chance
16%
Avg 0.8mm if it rains
Cloud Cover
49%
Overcast
Pressure
1019.7 hPa
Medium volatility
Cape Town Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 94% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
06:00 - 10:00
16:00 - 18:00
Type I-II
🔴 24 min to burn
Type III-IV
🟡 36 min to burn
Type V-VI
🟢 60 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
14°C
Pleasant
Heat Stress
Low
No heat warning
🙂 Best outdoor time:
Any time during daylight hours
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
❄️ Cold Water Hazard
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in South Africa
Flight Traffic
High
81/100 pressure index
Health Advisory
Required
2 vaccines • View Details →
Landing Slots
~109
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Cape Town
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
06:44
☀️ Noon
12:42
🌇 Sunset
18:40
⏱️ Daylight
11h 55m
Wind Speed
20.4 km/h
Moderate wind
Sunshine
9.9 hrs
Direct Sun (Cloud-free)
Humidity
76%
Humid / Damp
Travel Intelligence
Exclusive flight analytics & health data for Cape Town
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 Cape Town
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
Tourist Crowds
🟡 Busy
Price Level
💰💰💰 Expensive
Health & Wellbeing
Meteo-Health Forecast
Moderate fluctuations. Some sensitivity possible.
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, Cape Town on September 17 averages 18.3°C with a 16% precipitation probability. Wedding/Outdoor Event Score: 96/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Cape Town Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Better Alternatives Nearby
Consider these dates within ±7 days
September 10
18.3°C • 15% rain
Score
100
September 21
19°C • 14% rain
Score
100
September 20
18.9°C • 16% rain
Score
98
💡 Moving your event by a few days could significantly improve weather conditions
Compare Other Cities
Same date (September 17) in other destinations
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📍 Is Cape Town Worth Visiting on September 17?
Planning a trip to Cape Town on September 17? Our historical weather analysis based on 30 years of NASA satellite data shows that this time of year is characterized by pleasant mild weather averaging 18.3°C with a 16% historical precipitation risk.
✈️ Travel Logistics: Approximately 109 landing slots available daily during this period, indicating manageable crowd levels.
💉 Health Advisory: 9 vaccinations are recommended for South Africa, including COVID-19.
🌊 Coastal Conditions: Water temperature averages 14.4°C (polar plunge). Wave conditions are generally surfers only with heights around 3.49m.
📊 Historical Extremes: The hottest September 17 recorded in the last 30 years saw temperatures hit 24.5°C in 2017, while the coldest dropped to 7.2°C in 2023.