September 21 is statistically one of the best days of the year in Los Angeles. With minimal rain risk (2%) and pleasant highs of 29°C, it's ideal for outdoor adventures. Expect a bustling atmosphere in Los Angeles right now—this is when the city truly comes alive with visitors.
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Essential Travel Info for Los Angeles
Currency
USD
$ United States dollar
Language
English
Driving
Right side
Connect
Internet cafes are spread around town an...
Safety
Moderate Safety
GPI: 2.44
Los Angeles Weather Forecast for September 21
"Warm & Sunny. Expect average highs of 29.4°C. 2% chance of rain."
What to Wear in Los Angeles in September
Based on historical data for September 21, Los Angeles typically experiences temperatures between 16.3°C and 29.4°C. We recommend packing t-shirt, light clothing, layers (onion system) to stay comfortable. Trends suggest it will stay mostly dry (2% rain probability), but checking the forecast before heading out is always wise.
Complete Packing Guide
Weekly breakdown & essential items for Los Angeles
Smart Suitcase
- T-Shirt
- Light Clothing
- Layers (Onion System)
Average High
29.4°C
Daytime Peak
Average Low
16.3°C
Nighttime Low
Feels Like
32.3°C
🔥 Feels warmer
Rain Chance
2%
Avg 0mm if it rains
Cloud Cover
26%
Overcast
Pressure
1012 hPa
Low volatility
Los Angeles Weather Conditions & UV Index
Weather Confidence
30-year variance analysis
Based on 10 years of data
🎯 This date historically delivers consistent weather 82% of the time. Safe to plan outdoor activities with confidence.
Sun Exposure
UV Index & Safety Guide
Protection Needed
SPF 30 recommended
05:00 - 09:30
16:00 - 17:00
Type I-II
🔴 20 min to burn
Type III-IV
🟡 30 min to burn
Type V-VI
🟢 50 min to burn
UV estimate based on latitude, season & cloud cover. Actual UV may vary.
Outdoor Comfort
How pleasant is it outside?
Dew Point
21.6°C
Humid/Sticky
Heat Index
32.3°C
Feels hotter
🙂 Best outdoor time:
Any time during daylight hours
Marine Conditions
Marine Life
No special warnings. Enjoy the swim!
Swim Index
⚠️ Mixed Conditions
Travel & Logistics Insights
Local Calendar
Business Day
Standard hours in United States
Flight Traffic
High
98/100 pressure index
Health Advisory
Healthy
Routine only • View Details →
Landing Slots
~822
Daily arrival options (inc. codeshare)
Sunrise, Sunset & Wind in Los Angeles
Daylight & Sun
Solar Elevation Cycle
🌅 Sunrise
05:41
☀️ Noon
11:47
🌇 Sunset
17:53
⏱️ Daylight
12h 11m
Wind Speed
13.7 km/h
Gentle breeze
Sunshine
10.6 hrs
Direct Sun (Cloud-free)
Humidity
63%
Slightly humid
Travel Intelligence
Exclusive flight analytics & health data for Los Angeles
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 Los Angeles
Travel Comfort Index
Real-time tourism conditions
Weather Quality
☀️ Excellent
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 acceptable. Sensitive individuals should limit prolonged outdoor exertion.
Regional Safety Profile
Seismic Activity
Moderate seismic activity. Occasional tremors possible.
Eastern Pacific Hurricane Risk
Season: May - Nov
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, Los Angeles on September 21 averages 29.4°C with a 2% precipitation probability. Wedding/Outdoor Event Score: 100/100."
— Source: 30YearWeather.com|Data: NASA POWER (1991-2021)|View Methodology
Los Angeles Weather History (2010–2024)
Temperature History
Hall of Fame
Records from last 10 years
Compare Other Cities
Same date (September 21) in other destinations
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🌍 Explore the same date in different destinations around the world
📍 Is Los Angeles Worth Visiting on September 21?
Planning a trip to Los Angeles 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 29.4°C with a 2% historical precipitation risk.
✈️ Travel Logistics: Approximately 822 landing slots available daily during this period, indicating peak tourist activity.
🌊 Coastal Conditions: Water temperature averages 21°C (refreshing tonic). Wave conditions are generally fun waves with heights around 0.66m.
📊 Historical Extremes: The hottest September 21 recorded in the last 30 years saw temperatures hit 36.4°C in 2021, while the coldest dropped to 14.6°C in 2024.