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
The initiation of September sees an average high-temperature of a warm 84.7°F (29.3°C), showing minor variations from the previous month. Significant dips from daytime highs mark the September nights, with a consistent average temperature of 57.4°F (14.1°C).Heat index
The heat index for September is evaluated at a tropical 86°F (30°C). If one persists in activity during exposure, it could induce weariness and subsequently, heat cramps.Heat index data is primarily for areas with shade and subjected to 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', provides an understanding of perceived warmth by combining temperature and relative humidity. The effect is personal, with varied weather perceptions among individuals due to differences in body mass, stature, and physical activity. When exposed to direct sunlight, it's possible for the heat index to increase by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Children frequently do not comprehend the need for rest and hydration. Thirst is an advanced stage of dehydration - staying hydrated, especially during extended physical exercises, is essential.
Humidity
In September, the average relative humidity is 48%.Rainfall
In September, the rain falls for 1.6 days. Throughout September, 0.08" (2mm) of precipitation is accumulated. In Greenfield, during the entire year, the rain falls for 62.4 days and collects up to 9.45" (240mm) of precipitation.Daylight
The average length of the day in September is 12h and 23min.On the first day of the month, sunrise is at 6:37 am and sunset at 7:32 pm. On the last day of September, sunrise is at 6:59 am and sunset at 6:49 pm PDT.
Sunshine
In Greenfield, the average sunshine in September is 11.5h.UV index
The average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: In September, the maximum UV index of 5 transforms into these recommendations:
Guard yourself - An obligation to protect skin and eyes from harm exists. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the average humidity in September?
How much does it rain in September?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Greenfield have in September?
How high is the UV index in September?
Average temperature in September
Greenfield, CA
- Average high temperature in September: 84.7°F
The warmest month (with the highest average high temperature) is July (89.1°F).
The month with the lowest average high temperature is December (56.8°F).
- Average low temperature in September: 57.4°F
The month with the highest average low temperature is August (58.6°F).
The coldest month (with the lowest average low temperature) is December (40.8°F).
Average pressure in September
Greenfield, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in September
Greenfield, CA
- Average wind speed in September: 4.7mph
The windiest month (with the highest average wind speed) is May (6.3mph).
The calmest month (with the lowest average wind speed) is November (4.5mph).
Average humidity in September
Greenfield, CA
- Average humidity in September: 48%
The month with the highest relative humidity is February (70%).
The month with the lowest relative humidity is July (46%).
Average rainfall in September
Greenfield, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is December (1.89").
The driest month (with the least rainfall) is August (0.04").
Average rainfall days in September
Greenfield, CA
- Average rainfall days in September: 1.6 days
The month with the highest number of rainy days is March (11.8 days).
The month with the least rainy days is August (0.4 days).
Average daylight in September /
Average sunshine in September
Greenfield, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 36min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in September: 11h and 3min
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 6min).
Average sunshine days in September
Greenfield, CA
- Average sunshine days in September: 27.7 days
The month with the most sunshine days is August (30.1 days).
The month with the least sunshine days is March (18.3 days).
Average UV index in September
Greenfield, CA
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in September
Greenfield, CA
- Average cloud cover in September: 6
The months with the most cloud cover are March and December (Cloud cover 32).
The months with the least cloud cover are July and August (Cloud cover 4).
Average visibility in September
Greenfield, 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).
Greenfield, California, USA
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