United StatesAverage weather for California in September
It's hot in September in California with an average temperature of 33°C. Temperatures this month range from a low of 29°C to a high of 38°C. At night, you can expect temperatures between 15°C and 20°C.
Start of September
The month of September starts in California with hot temps, averaging around 37°C during the day and nights around 20°C. No precipitation expected at the start of the month; it’ll be sunny.
Mid September
By mid-September, daytime temps drop to around 33°C, with nights around 18°C. No precipitation expected during this period, so you can enjoy plenty of sunshine.
Since it cools down at night, it’s a good idea to wear layers.
End of September
By the end of September, the average daytime temperature in California is around 32°C, while nighttime temps are about 17°C. No precipitation expected at the end of the month; it’ll be mostly sunny.
Because temperatures drop in the evening, wearing layers is recommended.
According to weather history, there is only 1 mm of precipitation in September. The wind speed is around 3 Bft, mostly coming from the West.
California in September |
New York | ||
|---|---|---|---|
 Average temperature |
33°C | 27°C | |
 Max. temperature |
38°C | 31°C | |
| Min. temperature |
29°C | -5°C | |
 Total precipitation |
1 mm | 57 mm | |
| Rainy days |
0 days | 9 days | |
August
UV index
The UV index is a maximum of 8 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.
Is September a good time to visit California?
September is an awesome month to be in California for sunny weather. You’ll have high temperatures and not much chance of rain this month.
Temperature records
With 46°C in 2022, California reached the highest temperature in September over the past 10 years. The lowest daytime temperature in this month was 21°C in 2017. The extreme nighttime temperatures ranged from a lowest recorded value of 9°C to a highest value of 28°C.
Check out the climate of California for all months and discover the best travel time
The climate in California is based on weather data from . Other places, like New York City, Miami or Los Angeles, might have different weather. You can check out all destinations in California to get the full picture of the climate.
Daily Temperature in September in California
This chart shows the average daily high and low temperatures in September for California, in degrees Celsius. The red line represents the highs, and the blue line shows the lows. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, provide the average temperatures for this month.
Daily Precipitation in September in California
The chart below shows the average daily precipitation in September for California, measured in millimeters over the past few years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are listed at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that it rained more often. But remember, it’s just an average, and every day can be different. Based on historical weather data for September, you can expect it to stay dry all month in California.
Daily UV index in September in California
This chart shows the average daily UV index in September in California, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in California over the years
This chart shows the average temperature in September in California, measured in degrees Celsius, over the past few years.
Total precipitation in September in California over the years
This chart shows the average precipitation in September in California, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.
Daily weather in September for California
Click on any day in September to get detailed info about the usual weather on that day in California. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in California
Have you been to California in September?
Share your weather experience in September in California.
Average weather in California by month
Click on a month below to see detailed weather info for California. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of California for all months at once
