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
Vacaville, California, starts September with an average high-temperature of a still tropical 86.9°F (30.5°C), hinting at a minimal fluctuation from August. September nights in Vacaville show a substantial disparity from the daytime peak with an average low-temperature of 58.1°F (14.5°C).Heat index
September's average heat index is appraised at a hot 87.8°F (31°C). Ongoing activity coupled with exposure often results in weariness and could induce heat cramps.Be informed that the heat index values are oriented around shady conditions and gentle breezes. Heat index values have the potential to be boosted by 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
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 effect of weather is individual, with a variety of people experiencing it differently due to distinctions in body mass, height, and level of activity. Keep aware, the sun, when shining directly, can intensify the heat experience, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Youngsters typically face more danger than adults since they sweat less. Their larger skin surface compared to their small bodies and heightened heat production from their activities augment their vulnerability.
Humidity
With an average relative humidity of 48%, September is the least humid month.Rainfall
July through September are months with the least rain when the rain falls for 1.4 days and typically aggregates up to 0.04" (1mm) of rain.Daylight
In September, the average length of the day is 12h and 25min.On the first day of September, sunrise is at 6:38 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:03 am and sunset at 6:51 pm PDT.
Sunshine
The average sunshine in September is 11.2h.UV index
In Vacaville, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for the ordinary person.Note: In September, a regular UV index of 5 translates into these guidelines:
Guard yourself - An obligation to protect skin and eyes from harm exists. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Is it hot in Vacaville during September?
What is the least humid month in Vacaville?
What is the average humidity in September in Vacaville?
What is the driest month in Vacaville?
How much does it rain in Vacaville in September?
How many hours of daylight does Vacaville have in September?
When are sunrise and sunset in September in Vacaville?
How long on average sun shines in September in Vacaville?
How high is the UV index in September in Vacaville?
Average temperature in September
Vacaville, CA
- Average high temperature in September: 86.9°F
The warmest month (with the highest average high temperature) is July (91°F).
The month with the lowest average high temperature is December (54.7°F).
- Average low temperature in September: 58.1°F
The month with the highest average low temperature is September (58.1°F).
The coldest months (with the lowest average low temperature) are January and December (41.4°F).
Average pressure in September
Vacaville, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June and August (29.91"Hg).
Average wind speed in September
Vacaville, CA
- Average wind speed in September: 5.5mph
The windiest months (with the highest average wind speed) are May and June (6.8mph).
The calmest months (with the lowest average wind speed) are January and November (4.7mph).
Average humidity in September
Vacaville, CA
- Average humidity in September: 48%
The month with the highest relative humidity is March (75%).
The month with the lowest relative humidity is September (48%).
Average rainfall in September
Vacaville, CA
- Average rainfall in September: 0.04"
The wettest month (with the highest rainfall) is February (0.87").
The driest months (with the least rainfall) are July, August and September (0.04").
Average rainfall days in September
Vacaville, CA
- Average rainfall days in September: 1.4 days
The month with the highest number of rainy days is March (7.2 days).
The month with the least rainy days is August (1 days).
Average daylight in September /
Average sunshine in September
Vacaville, CA
- Average daylight in September: 12h and 2min
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 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 42min).
Average sunshine days in September
Vacaville, CA
- Average sunshine days in September: 27.8 days
The month with the most sunshine days is July (29.8 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in September
Vacaville, 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 January, February, November and December (UV index 3).
Average cloud cover in September
Vacaville, CA
- Average cloud cover in September: 9
The months with the most cloud cover are March and December (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 5).
Average visibility in September
Vacaville, 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).
Vacaville, California, USA
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