Los Angeles Weather in September
United States · Mediterranean climate · Data averaged from 2020-01-01 to 2024-12-31 (5 years)
September in Los Angeles sees average temperatures ranging from a low of 17.6°C (63.7°F) to a high of 31.1°C (88.0°F), with a mean of 23.1°C (73.6°F). Compared to the annual average of 17.8°C (64.0°F), this month is 5.3°C warmer than the yearly norm. Precipitation averages 16.7mm, making it approximately 24.0mm drier than the monthly average of 40.0mm. The city receives an average of 10.7 hours of sunshine per day during September, with relative humidity averaging 65.3%. Wind speeds reach an average maximum of 18.5 km/h. For travelers, this month offers a temperature experience in Los Angeles, with drier-than-average conditions compared to the rest of the year.
LA's reputation for perfect weather is mostly earned — but the microclimates will trick you. I packed for Santa Monica's 22°C and froze in Pacific Palisades' morning fog. September is the secret heat wave: 30°C inland, smoggy, oppressive. Pack layers even in summer — the marine layer keeps the coast 5°C cooler than 5km inland. May and October are my favorite windows: clear, 23°C, less traffic. Skip July-August if you're beach-phobic; the crowds at Venice are intense. December-March is underrated — 18°C, empty hiking trails, occasional dramatic rain.
September vs Adjacent Months
| Metric | August | September | October |
|---|---|---|---|
| Mean Temp | 23.7°C (74.7°F) | 23.1°C (73.6°F) | 20.3°C (68.5°F) |
| Rainfall | 17.6mm | 16.7mm | 6.3mm |
| Sunshine | 12.1 hrs | 10.7 hrs | 9.8 hrs |
| Humidity | 65.7% | 65.3% | 59.4% |
| Wind | 19.2 km/h | 18.5 km/h | 16.6 km/h |
| Rainy Days | 1.6 | 3.8 | 2.8 |
Seasonal Context
September falls in Autumn in the Northern Hemisphere. Autumn sees temperatures gradually cooling from summer highs. For travelers visiting Los Angeles in September, the data indicates favorable conditions based on the combination of temperature, precipitation, and daylight hours.
Frequently Asked Questions
What is the average temperature in Los Angeles in September?
The average temperature in Los Angeles during September ranges from 17.6°C (63.7°F) to 31.1°C (88.0°F), with a mean of 23.1°C (73.6°F).
How much does it rain in Los Angeles in September?
Los Angeles receives an average of 16.7mm of precipitation in September, spread across approximately 3.8 rainy days.
What should I pack for Los Angeles in September?
Based on September weather data, pack layers including light jackets and t-shirts, plus an umbrella.
Is September a good time to visit Los Angeles?
September is a good time to visit Los Angeles, with comfortable temperatures and manageable rainfall.
Other Months for Los Angeles
Cities with Similar September Climate (Mediterranean)
Data Source: Open-Meteo historical archive (2020-01-01 to 2024-12-31). Daily measurements aggregated into monthly climate normals. Coordinates: 34.05°, -118.24°. Timezone: America/Los_Angeles. Last updated: 2026-07-30.