Los Angeles (LA) weather in September
September in Los Angeles: hot, dry — an excellent time to visit.
Updated September 2026 · climate normals from ERA5 reanalysis
#7 of 12 months in Los Angeles · #449 of 1413 destinations to visit in September · comfort 86/100 (tier A)
- Days
- 30°C
- Nights
- 19°C
- Wet days
- 1
- Sun
- 11.2 h
- Humidity
- 56%
- Daylight
- 12 h

What September is like in Los Angeles
The hottest days of the year often fall now, driven by Santa Ana winds, which also open the worst of the fire weather.
smokesea warm
confidence: high
Traveller notes on Los Angeles in September
September is Los Angeles's hottest month, and the forum's advice is mostly about where you stand in it: near the ocean it stays mild, while the inland valleys run far hotter and a Santa Ana heat wave can push them past 40°C. Early September often pairs the heat with humidity; regulars say that usually eases later in the month, leaving late September and October sunny and pleasant. Their most practical tip is scheduling — don't do the uphill walk to Universal between 11 and 3.
Other months in Los Angeles
June gloom is a daily timetable rather than a season. The marine layer forms offshore, sits over the coast at breakfast, burns off through the late morning, and marches back in from the ocean about five - and the beaches are the last to clear, sometimes not at all. A few blocks inland can be five to fifteen degrees warmer on the same afternoon, which is why downtown barely notices it. Our row averages the whole basin at 27.7C reading as 29C with 13.1 hours of sun, and the number that matters at the coast is a 17.5C sea. Rain has stopped, 1.8mm in the month. The record: humidity 59 percent, a dew point of 13.3C, a 13.8 kph wind and AQI 56.
Asked whether mid-April is beach weather here, regulars split the question: the sand yes, the water no. Our sea column is why - 14.7C, which is swimming for the committed and paddling for everyone else, under air of 24.2C. They also warn that the coast and the inland city are different places on the same day, the beach in the low seventies while Hollywood is in the eighties, so the decision about a sweater is made by geography rather than forecast. Rain has effectively stopped, 15.9mm across 1.9 days, with 11.5 hours of sun. Nights fall to 12.9C, which surprises people. The record: humidity 61 percent, a dew point of 8.3C, a 14.9 kph wind and AQI 79.
Los Angeles-forum threads on 'May Gray' describe a coastal-only phenomenon: morning low cloud and fog that can keep the beach socked in past midday, while neighborhoods five miles inland sit under blue sky and run 10-20 degrees warmer at the same hour. Regulars call it a legitimate pattern but say it barely changes anyone's plans - people still walk the boardwalk and play volleyball through it, and it typically burns off by early afternoon. May's record backs the two-zone read: 23.8C days, 14.2C nights, almost no precipitation at under two days, 12.1 hours of sun and a 16.7C sea still on the cool side of comfortable.
LA forum threads describe January as genuinely variable, with average highs around 65F but real swings possible from the 50s up toward 80F depending on the week - posters described three days of rain followed by a week of sun as entirely normal rather than unusual. Layering was the universal packing advice given how much the day-to-night and coast-to-inland temperature swing can be. Ocean water was described as too cold for swimming without a wetsuit and beach lounging generally isn't realistic this time of year, even on a warm, sunny day - the coast and the inland valleys can also run noticeably different from each other on the same day.
Year-round notes are on Los Angeles's overview. Add your own note from Los Angeles's card on the map.
Los Angeles climate normals — September
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Los Angeles in September
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
BusySummer break in United States(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Los Angeles's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherLos Angeles's weather doesn't swing hard through the year — comfort stays fairly steady in every month.
What's on in Los Angeles in September
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Season
Sea at its warmest
1 Aug – 30 SepSea warm enoughLate summer is the only stretch when the Pacific here is worth getting into without a wetsuit, and it lasts into the first half of October.
- Hazard
Santa Ana wind and fire season
15 Sep – 15 Dec · usuallySmoke seasonOffshore winds arrive over vegetation that has had no rain since spring, and the fire risk peaks before the first storms. Smoke can close the hills and the coast road for days. Source ↗
Nearby, and something's on
Within 300 km of Los Angeles — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Los Angeles?
Los Angeles in September — FAQ
- Is September a good time to visit Los Angeles?
- September in Los Angeles: hot, dry — an excellent time to visit. It ranks #7 of 12 months for Los Angeles on SeasonMap's comfort score (86/100).
- What is the weather like in Los Angeles in September?
- In September, Los Angeles averages a daily high of 30.4°C and a low of 18.5°C, with about 4.6 mm of rain over roughly 0.5 rainy days.
- What is the air quality in Los Angeles in September?
- Los Angeles has a mean US Air Quality Index of about 59 in September.
Within 300 km: Laguna Beach's Sawdust Art Festival around 24 Jun – 6 Sep, and Santa Barbara's Blue and humpback season around 15 May – 15 Sep.