Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
September's arrival signals a moderate reduction in the average high-temperature, easing from 93.9°F (34.4°C) in August to a still tropical 87.4°F (30.8°C). Stonyford experiences a substantial divergence from daytime highs in September, with average lows hovering around a mild 59.9°F (15.5°C).Humidity
July through September, with an average relative humidity of 35%, are the least humid months.Rainfall
In September, the rain falls for 2.2 days. Throughout September, 0.12" (3mm) of precipitation is accumulated. Throughout the year, there are 71.4 rainfall days, and 14.02" (356mm) of precipitation is accumulated.Daylight
In September, the average length of the day is 12h and 26min.On the first day of the month, sunrise is at 6:39 am and sunset at 7:40 pm. On the last day of September, sunrise is at 7:06 am and sunset at 6:53 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 of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: A typical high UV index of 5 in September suggests the following recommendations:
Put precautions into practice - Ensuring skin and eye safety is a necessity. When the Sun is at its strongest around midday, find shade and limit exposure. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What are the least humid months?
What is the average humidity in September?
How much does it rain in September?
How many hours of daylight does Stonyford have in September?
When are sunrise and sunset in September in Stonyford?
How many hours of sunshine does Stonyford have in September?
How high is the UV index in September?
Average temperature in September
Stonyford, CA
- Average high temperature in September: 87.4°F
The warmest month (with the highest average high temperature) is July (95.4°F).
The month with the lowest average high temperature is December (52.7°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (63.1°F).
The coldest month (with the lowest average low temperature) is December (39.4°F).
Average pressure in September
Stonyford, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The months with the lowest atmospheric pressure are June, July and August (29.91"Hg).
Average wind speed in September
Stonyford, CA
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is March (6.1mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in September
Stonyford, CA
- Average humidity in September: 35%
The month with the highest relative humidity is March (69%).
The months with the lowest relative humidity are July, August and September (35%).
Average rainfall in September
Stonyford, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is February (2.68").
The driest month (with the least rainfall) is July (0.04").
Average rainfall days in September
Stonyford, CA
- Average rainfall days in September: 2.2 days
The month with the highest number of rainy days is March (12.5 days).
The month with the least rainy days is July (1 days).
Average daylight in September /
Average sunshine in September
Stonyford, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in September: 11h and 1min
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
Stonyford, CA
- Average sunshine days in September: 27.3 days
The month with the most sunshine days is July (29.8 days).
The month with the least sunshine days is March (17 days).
Average UV index in September
Stonyford, 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
Stonyford, CA
- Average cloud cover in September: 8
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in September
Stonyford, 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).
Stonyford, California, USA
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