September weather forecastRocklin, CA
September
Weather in September
September, the first month of the autumn in Rocklin, is still a tropical month, with temperature in the range of an average low of 58.8°F (14.9°C) and an average high of 87.8°F (31°C).Temperature
On the advent of September, Rocklin's average high-temperature exhibits a minor adjustment to a still tropical 87.8°F (31°C) from August's 92.8°F (33.8°C). A noticeable downturn in temperature characterizes the September nights, averaging at a mild 58.8°F (14.9°C).Heat index
For most parts of September, the heat index is computed to be a hot 87.8°F (31°C). Enduring exposure and ongoing activity could cause a sense of fatigue and subsequent heat cramps.Heat index values are typically calculated for conditions of shade and a light breeze. Being under direct sunlight might amplify the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', is a numerical representation of warmth when taking temperature and moisture levels into account. The impact of weather is individual, with diverse individuals experiencing it differently due to variations in body mass, height, and activity levels. Given direct exposure to sunlight, one might experience a rise in the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Children often lack awareness of the importance of taking breaks and rehydrating. The feeling of thirst is a late indication of dehydration, so maintaining hydration, especially during long periods of physical activity, is critical.
Humidity
In Rocklin, the average relative humidity in September is 42%.Rainfall
In Rocklin, during September, the rain falls for 2.4 days and regularly aggregates up to 0.2" (5mm) of precipitation. In Rocklin, during the entire year, the rain falls for 78.4 days and collects up to 19.09" (485mm) of precipitation.Snowfall
In Rocklin, snow does not fall in January through November.Daylight
The average length of the day in September is 12h and 25min.On the first day of September in Rocklin, sunrise is at 6:34 am and sunset at 7:34 pm. On the last day of the month, sunrise is at 7:00 am and sunset at 6:48 pm PDT.
Sunshine
The average sunshine in September is 11.2h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV radiation for average individuals.Note: During September, 5 as the daily maximum UV index converts into the following advice:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. Direct Sun exposure should be minimized especially during midday when radiation is most intense. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rocklin, CA
- Average high temperature in September: 87.8°F
The warmest month (with the highest average high temperature) is July (94.1°F).
The month with the lowest average high temperature is December (54.1°F).
- Average low temperature in September: 58.8°F
The month with the highest average low temperature is July (60.4°F).
The coldest month (with the lowest average low temperature) is December (40.5°F).
Average pressure in September
Rocklin, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Rocklin, CA
- Average wind speed in September: 4mph
The windiest month (with the highest average wind speed) is February (5.7mph).
The calmest month (with the lowest average wind speed) is September (4mph).
Average humidity in September
Rocklin, CA
- Average humidity in September: 42%
The month with the highest relative humidity is March (74%).
The month with the lowest relative humidity is July (41%).
Average rainfall in September
Rocklin, CA
- Average rainfall in September: 0.2"
The wettest month (with the highest rainfall) is March (3.58").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in September
Rocklin, CA
- Average rainfall days in September: 2.4 days
The month with the highest number of rainy days is March (14.1 days).
The month with the least rainy days is July (1.1 days).
Average snowfall days in September
Rocklin, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.2 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Rocklin, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 11h and 12min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in September
Rocklin, CA
- Average sunshine days in September: 27 days
The month with the most sunshine days is July (29.3 days).
The month with the least sunshine days is March (15.8 days).
Average UV index in September
Rocklin, CA
- Average UV index in September: 5
The months with the highest UV index are June and July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Rocklin, CA
- Average cloud cover in September: 8
The month with the most cloud cover is March (Cloud cover 38).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in September
Rocklin, 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).





