September weather forecastRochester, CA
September
Weather in September
September, the first month of the autumn in Rochester, is also a hot month, with an average temperature ranging between min 63.7°F (17.6°C) and max 88.3°F (31.3°C).Temperature
With the advent of September, Rochester's high-temperatures adjust to a still hot 88.3°F (31.3°C), closely aligning with the preceding month. The nighttime temperature shows a significant divergence from the daytime highs, averaging at a comfortable 63.7°F (17.6°C) in September.Heat index
During September, the heat index is estimated at a hot 89.6°F (32°C). If one continues to be active during exposure, it might cause tiredness and subsequent heat cramps.Research indicates the heat index considers values in shaded locales and with light winds. Direct sunshine exposure could raise heat index values by as much as 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'felt air temperature', combines air temperature and relative humidity to represent a human perceived temperature equivalent. The individual's temperature perception can be influenced by numerous factors such as metabolic variations, physical activity, and clothing. Keep it in mind, direct sunlight can augment the heat you experience, possibly pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Children regularly disregard the necessity to rest and replenish fluids. Thirst is a late symptom of dehydration - thus, maintaining hydration, particularly during long-lasting physical activities, is essential.
Humidity
The average relative humidity in September in Rochester is 43%.Rainfall
In Rochester, in September, it is raining for 1.8 days, with typically 0.08" (2mm) of accumulated precipitation. In Rochester, California, during the entire year, the rain falls for 42.3 days and collects up to 4.53" (115mm) of precipitation.Snowfall
January, March through December are months without snowfall in Rochester.Daylight
The average length of the day in September in Rochester, California, is 12h and 22min.On the first day of the month, sunrise is at 6:24 am and sunset at 7:15 pm. On the last day of September, sunrise is at 6:44 am and sunset at 6:35 pm PDT.
Sunshine
In September, the average sunshine in Rochester is 10.7h.UV index
In Rochester, the average daily maximum UV index in September is 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from exposure to the Sun's UV radiation for the ordinary person.Note: The maximum daily UV index of 6 in September converts into the following recommendations:
Enforce precautions and stick to sun safety measures. Preservation from skin and eye damage is essential. Attempt to stay under shade and limit exposure to the Sun between 10 a.m. and 4 p.m., when UV radiation is at its peak. Remember, devices such as parasols or canopies might not provide complete sun protection. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Rochester, CA
- Average high temperature in September: 88.3°F
The warmest month (with the highest average high temperature) is August (91.8°F).
The month with the lowest average high temperature is December (61.7°F).
- Average low temperature in September: 63.7°F
The month with the highest average low temperature is August (66.6°F).
The coldest months (with the lowest average low temperature) are February and December (45.3°F).
Average pressure in September
Rochester, CA
- Average pressure in September: 29.88"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Rochester, CA
- Average wind speed in September: 4.5mph
The windiest month (with the highest average wind speed) is May (5.9mph).
The calmest month (with the lowest average wind speed) is September (4.5mph).
Average humidity in September
Rochester, CA
- Average humidity in September: 43%
The months with the highest relative humidity are February, March and May (53%).
The month with the lowest relative humidity is August (41%).
Average rainfall in September
Rochester, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is February (0.98").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
Rochester, CA
- Average rainfall days in September: 1.8 days
The month with the highest number of rainy days is March (6.3 days).
The month with the least rainy days is June (0.9 days).
Average snowfall days in September
Rochester, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Rochester, 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 months with the least sunshine are February and December (Average sunshine: 6h and 54min).
Average sunshine days in September
Rochester, CA
- Average sunshine days in September: 26 days
The month with the most sunshine days is June (28.3 days).
The month with the least sunshine days is February (22.8 days).
Average UV index in September
Rochester, CA
- Average UV index in September: 6
The months with the highest UV index are July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
Rochester, CA
- Average cloud cover in September: 6
The months with the most cloud cover are February and December (Cloud cover 21).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
Rochester, 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).
