September weather forecastHacienda Heights, CA
September
Weather in September
September, the first month of the autumn in Hacienda Heights, is also a moderately hot month, with an average temperature varying between 64.6°F (18.1°C) and 85.8°F (29.9°C).Temperature
Hacienda Heights, California, experiences a subtle adjustment in high-temperatures to a moderately hot 85.8°F (29.9°C) with the onset of September, maintaining near parity with August's 87.6°F (30.9°C). Hacienda Heights experiences a mean low-temperature of 64.6°F (18.1°C) during September.Heat index
In September, the heat index is calculated to be a tropical 87.8°F (31°C). Ongoing exposure and activity could lead to a state of exhaustion, with a chance of heat cramps.Remember that heat index calculations are made for conditions in the shade with light wind. Heat index values may rise by up to 15 Fahrenheit (8 Celsius) degrees when exposed to direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', unifies temperature and humidity readings to offer a comprehensive feel of warmth. Elements of metabolic variation, physical activity, and clothing contribute to the effect of temperature on an individual. Exposure to direct sun rays can influence the heat you feel, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly important for children. Young people are generally more susceptible than adults because they perspire less. Furthermore, their proportionally larger skin surface to their petite bodies and the increased heat output from their actions add to the risk.
Humidity
In September, the average relative humidity is 51%.Rainfall
In Hacienda Heights, during September, the rain falls for 2.5 days and regularly aggregates up to 0.08" (2mm) of precipitation. Throughout the year, there are 40.9 rainfall days, and 6.3" (160mm) of precipitation is accumulated.Daylight
In Hacienda Heights, 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 6:36 pm PDT.
Sunshine
In September, the average sunshine in Hacienda Heights is 10.6h.UV index
In September, the average daily maximum UV index is 6. A UV Index value of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV rays for average individuals.Note: The daily high UV index of 6 in September translates into this advice:
Exercise precautions and adapt sun safety practices. Defence against skin and eye affliction is paramount. Remember that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. Make an effort to avoid direct sun exposure during these hours. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Hacienda Heights, CA
- Average high temperature in September: 85.8°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 (64.9°F).
- Average low temperature in September: 64.6°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 (49.3°F).
Average pressure in September
Hacienda Heights, 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
Hacienda Heights, 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
Hacienda Heights, CA
- Average humidity in September: 51%
The month with the highest relative humidity is June (60%).
The month with the lowest relative humidity is November (47%).
Average rainfall in September
Hacienda Heights, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is December (1.46").
The driest months (with the least rainfall) are June and August (0.04").
Average rainfall days in September
Hacienda Heights, CA
- Average rainfall days in September: 2.5 days
The month with the highest number of rainy days is March (5.8 days).
The month with the least rainy days is June (1.2 days).
Average daylight in September /
Average sunshine in September
Hacienda Heights, 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 36min
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 42min).
Average sunshine days in September
Hacienda Heights, CA
- Average sunshine days in September: 26.3 days
The month with the most sunshine days is August (28.6 days).
The month with the least sunshine days is February (22.6 days).
Average UV index in September
Hacienda Heights, 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
Hacienda Heights, CA
- Average cloud cover in September: 9
The months with the most cloud cover are February, March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
Hacienda Heights, 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).
