Los Angeles Weather in September
September continues the pleasant summer weather that Los Angeles, California enjoys. It's another month where you can expect plenty of sun, no rain and moderately hot temperatures.
This page gives detailed information on the typical September temperature, precipitation, sun, humidity, wind and storms for Los Angeles. The temperature, rainfall, sunshine and wind speed numbers here are historical averages based on climate data gathered in downtown Los Angeles near Union Station. The humidity and thunderstorm measurements are averages at the Los Angeles International Airport, located southwest of the city center.
|83 °F||September average high||28 °C|
|64 °F||September average low||18 °C|
|21 days||80 °F max. or more (27 °C)|
|6 days||60 °F min. or less (16 °C)|
Typically every day in September warms to over 70 degrees Fahrenheit (21 degrees Celsius) in Los Angeles. The city averages six days this month when the thermometer reaches into the 90s °F (over 32 °C). In some years, a temperature of 100 °F (38 °C) or more can occur briefly during September.
The thermometer drops to 70 °F (21 °C) or below on most nights. But September does not normally cool down to 50 °F (10 °C).
|0.1 in||total precipitation||3 mm|
|0 day||of rain|
Most years, Los Angeles gets no precipitation at all in September.
|18 days||clear skies|
The sun's rays reach the ground in Los Angeles during 79 percent of daylight hours on average in September, for a total of 293 hours in the month. Typically on 18 days this month the sky is mainly clear, with at most 30 percent cloud cover.
Sunlight in September at Los Angeles lasts for 12 hours and 21 minutes a day on average. The longest day of the month is the 1st with 12 hours and 52 minutes of daylight. By the end of the month, the days have shortened to 11:51 from sunrise to sunset. These durations can vary by a minute or two from year to year.
|74 %||September average humidity|
The relative humidity in Los Angeles during September usually peaks at 83 percent in the morning then drops to 62 percent by early afternoon.
|Local Time||1 am||4 am||7 am||10 am||1 pm||4 pm||7 pm||10 pm|
|4.4 mph||September wind speed average||7.1 kph|
September is a little less windy than most other months in Los Angeles.
|0 days||rainfall of 0.5 inches (13 mm) or more|
|1 day||with thunderstorms in September|
Los Angeles averages a September thunderstorm every two years, and a heavy rainstorm about once a decade.
The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.