September weather forecastEl Monte, CA
September
Weather in September
September, the first month of the autumn in El Monte, is still a hot month, with an average temperature fluctuating between 63.5°F (17.5°C) and 86°F (30°C).Temperature
With September's arrival, El Monte's weather records an average high-temperature of a still hot 86°F (30°C), marking little difference from August's 87.6°F (30.9°C). A noticeable temperature swing characterizes El Monte's September nights, dipping to an average of 63.5°F (17.5°C).Heat index
For September, the heat index is calculated to be a hot 87.8°F (31°C). With extended exposure and activity, one might feel exhausted and experience heat cramps.It is crucial to understand that heat index figures are for shade and gentle wind conditions. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', arises from combining readings of air temperature and relative moisture content. Elements such as metabolic variations, pregnancy, and physical exertion can influence one's weather perception. It is essential to realize that direct sunlight can escalate the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Kids are usually in more danger than grown-ups as they tend to sweat less. Plus, their bigger skin surface in relation to their small frames and increased heat generation due to their activity level make them more susceptible.
Humidity
The average relative humidity in September is 50%.Rainfall
In El Monte, during September, the rain falls for 2.9 days and regularly aggregates up to 0.12" (3mm) of precipitation. Throughout the year, there are 43.3 rainfall days, and 5.91" (150mm) 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 6:26 am and sunset at 7:17 pm. On the last day of the month, sunrise is at 6:46 am and sunset at 6:37 pm PDT.
Sunshine
In September, the average sunshine in El Monte, California, is 10.7h.UV index
The average daily maximum UV index in September in El Monte, California, is 6. A UV Index reading of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: In September, the average maximum UV index of 6 translates into the following recommendations:
Uphold preventive measures and conform to sun safety guidelines. Defending against skin and eye harm is crucial. Seek shade and limit direct sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Keep in mind that shade structures like parasols or canopies do not offer complete sun protection. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
El Monte, CA
- Average high temperature in September: 86°F
The warmest month (with the highest average high temperature) is August (87.6°F).
The month with the lowest average high temperature is December (63.5°F).
- Average low temperature in September: 63.5°F
The month with the highest average low temperature is August (64.9°F).
The coldest months (with the lowest average low temperature) are February and December (47.3°F).
Average pressure in September
El Monte, 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
El Monte, CA
- Average wind speed in September: 4.5mph
The windiest month (with the highest average wind speed) is April (5.8mph).
The calmest months (with the lowest average wind speed) are September and October (4.5mph).
Average humidity in September
El Monte, CA
- Average humidity in September: 50%
The month with the highest relative humidity is June (58%).
The month with the lowest relative humidity is November (46%).
Average rainfall in September
El Monte, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is December (1.22").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
El Monte, CA
- Average rainfall days in September: 2.9 days
The month with the highest number of rainy days is March (5.3 days).
The month with the least rainy days is June (1.2 days).
Average daylight in September /
Average sunshine in September
El Monte, CA
- Average daylight in September: 12h and 24min
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 42min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is February (Average sunshine: 6h and 48min).
Average sunshine days in September
El Monte, CA
- Average sunshine days in September: 25.5 days
The month with the most sunshine days is June (27.6 days).
The month with the least sunshine days is February (22.6 days).
Average UV index in September
El Monte, 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 January, February, November and December (UV index 4).
Average cloud cover in September
El Monte, CA
- Average cloud cover in September: 7
The month with the most cloud cover is December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
El Monte, 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).





