Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
Fullerton measures an average high-temperature of a still moderately hot 82.2°F (27.9°C) in September, nearly consistent with the preceding month. Fullerton records a consistent low-temperature of 64.8°F (18.2°C) during September nights.Heat index
The average heat index in September is computed to be 84.2°F (29°C). Uninterrupted exposure and activity might result in fatigue, potentially causing heat cramps.Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. Direct exposure to sunshine could lead to a heat index increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', evaluates the perceived heat by adding the effect of moisture in the air. A person's impression of weather can be swayed by numerous aspects, among them metabolic variations, pregnancy, and activity levels. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Young individuals usually face greater risks than adults as their sweat production is less. Also, their larger skin surface relative to their small bodies and the high heat generation due to their activity contributes to their vulnerability.
Humidity
In September, the average relative humidity is 58%.Rainfall
In September, the rain falls for 3.5 days. Throughout September, 0.2" (5mm) of precipitation is accumulated. Throughout the year, there are 52.5 rainfall days, and 7.09" (180mm) of precipitation is accumulated.Daylight
In September, the average length of the day is 12h and 22min.On the first day of September, sunrise is at 6:26 am and sunset at 7:16 pm. On the last day of the month, sunrise is at 6:45 am and sunset at 6:36 pm PDT.
Sunshine
In September, the average sunshine is 10.6h.UV index
The months with the highest UV index are June through September, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.Note: The average daily UV index of 6 in September transforms into the following instructions:
Sidestep overexposure. Individuals with fair complexions risk burning in fewer than 20 minutes. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
How much does it rain in September?
What is the average length of the day in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Fullerton have in September?
What are the months with the highest UV index?
What is the UV index reading in September?
Average temperature in September
Fullerton, CA
- Average high temperature in September: 82.2°F
The warmest month (with the highest average high temperature) is August (83.5°F).
The month with the lowest average high temperature is December (64°F).
- Average low temperature in September: 64.8°F
The month with the highest average low temperature is August (65.5°F).
The coldest month (with the lowest average low temperature) is February (50.2°F).
Average pressure in September
Fullerton, CA
- Average pressure in September: 29.89"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
Fullerton, CA
- Average wind speed in September: 4.7mph
The windiest month (with the highest average wind speed) is April (6mph).
The calmest months (with the lowest average wind speed) are September and October (4.7mph).
Average humidity in September
Fullerton, CA
- Average humidity in September: 58%
The month with the highest relative humidity is June (65%).
The month with the lowest relative humidity is November (51%).
Average rainfall in September
Fullerton, CA
- Average rainfall in September: 0.2"
The wettest month (with the highest rainfall) is December (1.54").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
Fullerton, CA
- Average rainfall days in September: 3.5 days
The month with the highest number of rainy days is March (7.3 days).
The month with the least rainy days is June (1.5 days).
Average daylight in September /
Average sunshine in September
Fullerton, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 10h and 4min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in September
Fullerton, CA
- Average sunshine days in September: 23.4 days
The month with the most sunshine days is August (25.8 days).
The month with the least sunshine days is February (20.6 days).
Average UV index in September
Fullerton, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 4).
Average cloud cover in September
Fullerton, CA
- Average cloud cover in September: 9
The months with the most cloud cover are March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
Fullerton, CA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Fullerton, California, USA
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