September weather forecastRiverbank, CA
September
Weather in September
The first month of the autumn, September, is also a hot month in Riverbank, California, with an average temperature ranging between min 59.7°F (15.4°C) and max 90°F (32.2°C).Temperature
The transition into September is accompanied by a slight temperature decrease, with the average high-temperature shifting from a sweltering 95.5°F (35.3°C) in August to a tropical 90°F (32.2°C). Riverbank demonstrates a significant disparity from daytime highs throughout the month of September, with an average nighttime temperature of 59.7°F (15.4°C).Heat index
The heat index in September is evaluated at a tropical 91.4°F (33°C). Take more preventive steps, risk of heat exhaustion and heat cramps is elevated. Long activity may culminate in heatstroke.Heat index readings emphasize conditions of light breezes and shaded spots. Direct sunshine exposure could raise heat index values by as much as 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', comes about by integrating the temperature readings with the humidity levels. One's perception of temperature is subjective, varying based on their activity and individual heat perception, influenced by factors like wind, clothing, and metabolic variations. When in direct sunlight, one should be cautious as it can raise the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
Humidity
In September, the average relative humidity is 41%.Rainfall
In September, in Riverbank, California, the rain falls for 2 days. Throughout September, 0.08" (2mm) of precipitation is accumulated. In Riverbank, during the entire year, the rain falls for 59.3 days and collects up to 8.23" (209mm) of precipitation.Snowfall
January through November are months without snowfall in Riverbank.Daylight
The average length of the day in September in Riverbank is 12h and 25min.On the first day of the month, sunrise is at 6:34 am and sunset at 7:32 pm. On the last day of September, sunrise is at 6:59 am and sunset at 6:47 pm PDT.
Sunshine
In September, the average sunshine is 11.5h.UV index
In Riverbank, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for the ordinary person.Note: In September, the UV index of 5 transforms into the following advice:
Safety measures are advised. Light-skinned individuals may experience burns in under half an hour. Minimize direct exposure to the Sun during midday when its radiation is at its peak. 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
Riverbank, CA
- Average high temperature in September: 90°F
The warmest month (with the highest average high temperature) is July (96.4°F).
The month with the lowest average high temperature is December (55.4°F).
- Average low temperature in September: 59.7°F
The month with the highest average low temperature is July (62.1°F).
The coldest month (with the lowest average low temperature) is December (41°F).
Average pressure in September
Riverbank, CA
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Riverbank, CA
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is June (7.1mph).
The calmest month (with the lowest average wind speed) is November (4.9mph).
Average humidity in September
Riverbank, CA
- Average humidity in September: 41%
The month with the highest relative humidity is January (72%).
The month with the lowest relative humidity is July (37%).
Average rainfall in September
Riverbank, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is March (1.65").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in September
Riverbank, CA
- Average rainfall days in September: 2 days
The month with the highest number of rainy days is March (11.3 days).
The month with the least rainy days is August (0.7 days).
Average snowfall in September
Riverbank, CA
- Average snowfall in September: 0"
The month with the highest snowfall is December (0.04").
The months with the least snowfall are January, February, March, April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Riverbank, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.1 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
Riverbank, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 11h and 30min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in September
Riverbank, CA
- Average sunshine days in September: 26.8 days
The month with the most sunshine days is August (29.2 days).
The month with the least sunshine days is March (18.7 days).
Average UV index in September
Riverbank, 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
Riverbank, CA
- Average cloud cover in September: 6
The month with the most cloud cover is March (Cloud cover 33).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in September
Riverbank, 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).
