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
Atascadero records an average high-temperature of a still warm 83.3°F (28.5°C) in September, maintaining a close correlation with August's 85.5°F (29.7°C). Atascadero's September nights bring a significant temperature shift, averaging at a moderate 59.9°F (15.5°C).Heat index
September's mean heat index is evaluated at 84.2°F (29°C). If exposure and activity are sustained, they might cause a feeling of weariness, resulting in heat cramps.Remember that heat index calculations are made for conditions in the shade with light wind. With exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is a composite of temperature and humidity figures to convey how warm it feels. The individual's experience of temperature can be shaped by numerous aspects such as metabolic variations, physical exertion, and attire. Sunshine, when direct, has the potential to intensify weather effects, leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Young ones often disregard the necessity to rest and hydrate. Thirst usually indicates advanced dehydration - hence, it is key to stay hydrated, particularly during ongoing physical activities.
Humidity
With an average relative humidity of 50%, September is the least humid month.Rainfall
In Atascadero, in September, it is raining for 1.8 days, with typically 0.12" (3mm) of accumulated precipitation. Throughout the year, there are 54.8 rainfall days, and 8.66" (220mm) of precipitation is accumulated.Daylight
The average length of the day in September is 12h and 23min.On the first day of the month, sunrise is at 6:35 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:57 am and sunset at 6:47 pm PDT.
Sunshine
In September, the average sunshine is 11.3h.UV index
June through September, with an average maximum UV index of 6, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for the ordinary person.Note: A maximum high daily UV index of 6 during September translates into the following directions:
Ward off overexposure. Defence against solar harm is crucial. Between 10 a.m. and 4 p.m., UV radiation is strongest. Make an effort to avoid direct sunlight during this time, remembering that shade structures may not provide full sun protection. Stay sun-safe with clothing that is both closely woven and worn loosely.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the least humid month?
What is the average humidity in September?
How much does it rain in September?
How many hours of daylight does Atascadero have in September?
What time are sunrise and sunset in September?
How long on average sun shines in September?
What is the month with the highest UV index?
What is the UV index reading in September?
Average temperature in September
Atascadero, CA
- Average high temperature in September: 83.3°F
The warmest month (with the highest average high temperature) is August (85.5°F).
The month with the lowest average high temperature is December (58.5°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is September (59.9°F).
The coldest month (with the lowest average low temperature) is December (42.8°F).
Average pressure in September
Atascadero, CA
- Average pressure in September: 29.91"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.91"Hg).
Average wind speed in September
Atascadero, CA
- Average wind speed in September: 4.5mph
The windiest months (with the highest average wind speed) are March and April (5.9mph).
The calmest months (with the lowest average wind speed) are August and September (4.5mph).
Average humidity in September
Atascadero, CA
- Average humidity in September: 50%
The months with the highest relative humidity are February and March (68%).
The month with the lowest relative humidity is September (50%).
Average rainfall in September
Atascadero, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is March (1.73").
The driest months (with the least rainfall) are June and August (0.04").
Average rainfall days in September
Atascadero, CA
- Average rainfall days in September: 1.8 days
The month with the highest number of rainy days is March (10.2 days).
The month with the least rainy days is June (0.8 days).
Average daylight in September /
Average sunshine in September
Atascadero, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 11h and 2min
The months with the most sunshine are June and July (Average sunshine: 12h and 0min).
The months with the least sunshine are February and December (Average sunshine: 6h and 18min).
Average sunshine days in September
Atascadero, CA
- Average sunshine days in September: 28 days
The month with the most sunshine days is August (29.8 days).
The month with the least sunshine days is February (19.7 days).
Average UV index in September
Atascadero, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in September
Atascadero, CA
- Average cloud cover in September: 7
The month with the most cloud cover is March (Cloud cover 31).
The month with the least cloud cover is August (Cloud cover 6).
Average visibility in September
Atascadero, 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).
Atascadero, California, USA
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