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
Brea records an average high-temperature of a warm 84.2°F (29°C) as September arrives, nearly mirroring the previous month's climate. During the month of September, the temperature falls to an average of 64.9°F (18.3°C).Heat index
In September, the average heat index is calculated to be a hot 86°F (30°C). If one remains active during constant exposure, it might cause exhaustion and heat cramps.Heat index guidelines indicate values are for light wind scenarios and shaded regions. Direct sunlight might lead to a heat index increase by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', integrates the air's temperature and its humidity to showcase the felt temperature by people. An individual's temperature experience can be influenced by extra factors, including metabolic differences, activity levels, and clothing. It is noteworthy to mention that direct sunlight exposure can augment the felt temperature, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Younglings frequently fail to recognize the requirement to rest and rehydrate. Thirst emerges late in dehydration - it is imperative to keep hydration levels high, particularly during extended physical exertions.
Humidity
In September, the average relative humidity is 54%.Rainfall
In Brea, in September, it is raining for 2.6 days, with typically 0.12" (3mm) of accumulated precipitation. Throughout the year, in Brea, there are 45.6 rainfall days, and 6.5" (165mm) of precipitation is accumulated.Daylight
The average length of the day in September is 12h and 22min.On the first day of September, sunrise is at 6:25 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 average daily maximum UV index in September is 6. A UV Index reading of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV rays for average individuals.Note: A maximum daily UV index of 6 during September morphs into the following directions:
Persist with safeguards and heed sun safety doctrines. Keeping sunburn at bay is of prime importance. Avoid direct Sun exposure and seek shade from 10 a.m. to 4 p.m., the period of highest UV radiation. Remember, however, that not all shade structures offer full protection. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in September?
What is the average humidity in September?
How many days does it rain in September?
How many hours of daylight does Brea have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the UV index intensity in September?
Average temperature in September
Brea, CA
- Average high temperature in September: 84.2°F
The warmest month (with the highest average high temperature) is August (86°F).
The month with the lowest average high temperature is December (64.6°F).
- Average low temperature in September: 64.9°F
The month with the highest average low temperature is August (65.8°F).
The coldest month (with the lowest average low temperature) is February (49.8°F).
Average pressure in September
Brea, 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
Brea, CA
- Average wind speed in September: 4.7mph
The windiest month (with the highest average wind speed) is April (5.9mph).
The calmest months (with the lowest average wind speed) are September and October (4.7mph).
Average humidity in September
Brea, CA
- Average humidity in September: 54%
The month with the highest relative humidity is June (62%).
The month with the lowest relative humidity is November (49%).
Average rainfall in September
Brea, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is December (1.5").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
Brea, CA
- Average rainfall days in September: 2.6 days
The month with the highest number of rainy days is March (6.7 days).
The month with the least rainy days is June (1.3 days).
Average daylight in September /
Average sunshine in September
Brea, 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 months with the least sunshine are January, February and December (Average sunshine: 6h and 48min).
Average sunshine days in September
Brea, CA
- Average sunshine days in September: 24.6 days
The month with the most sunshine days is June (26.9 days).
The month with the least sunshine days is February (22.1 days).
Average UV index in September
Brea, CA
- Average UV index in September: 6
The month with the highest UV index is August (UV index 7).
The months with the lowest UV index are February, November and December (UV index 4).
Average cloud cover in September
Brea, CA
- Average cloud cover in September: 8
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
Brea, 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).
Brea, California, USA
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