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 commencement of September records an average high-temperature of a moderately hot 84.7°F (29.3°C), barely varying from August's 88.2°F (31.2°C). September nights bring a pronounced temperature shift, with averages hovering around a comfortable 61°F (16.1°C).Heat index
September's heat index is evaluated at 84.2°F (29°C). Continuous activity in exposure could lead to a feeling of fatigue and heat cramps.Note that heat index values are valued for light wind and location in the shade. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'real feel' or 'apparent temperature', ties air temperature with relative humidity to produce the perceived temperature sensation. Additional elements including metabolic differences, the level of physical activity, and attire have a role in shaping the individual's temperature perception. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Youngsters often neglect the necessity for rest and hydration. Thirst is a sign of advancing dehydration - thus the importance of maintaining hydration, specifically during long-lasting physical activities.
Humidity
The average relative humidity in September is 44%.Rainfall
In September, the rain falls for 2.3 days. Throughout September, 0.08" (2mm) of precipitation is accumulated. In Castaic, during the entire year, the rain falls for 42.2 days and collects up to 6.77" (172mm) of precipitation.Daylight
In September, the average length of the day is 12h and 22min.On the first day of September, sunrise is at 6:28 am and sunset at 7:20 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 6:39 pm PDT.
Sunshine
The average sunshine in September is 10.9h.UV index
In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for average individuals.Note: The daily high UV index of 5 during September translates into the following recommendations:
Act with care - The need to guard against sun damage is communicated. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. In bright sunlight, prioritize sunglasses that grant protection from UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in September?
What is the average humidity in September?
How many days does it rain in September?
How many hours of daylight does Castaic have in September?
What time are sunrise and sunset in September?
How many hours of sunshine does Castaic have in September?
How high is the UV index in September?
Average temperature in September
Castaic, CA
- Average high temperature in September: 84.7°F
The warmest month (with the highest average high temperature) is August (88.2°F).
The month with the lowest average high temperature is December (59.5°F).
- Average low temperature in September: 61°F
The month with the highest average low temperature is August (63.7°F).
The coldest month (with the lowest average low temperature) is December (42.3°F).
Average pressure in September
Castaic, CA
- Average pressure in September: 29.9"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
Castaic, CA
- Average wind speed in September: 5mph
The windiest months (with the highest average wind speed) are January and December (7.3mph).
The calmest month (with the lowest average wind speed) is August (4.9mph).
Average humidity in September
Castaic, CA
- Average humidity in September: 44%
The month with the highest relative humidity is March (56%).
The months with the lowest relative humidity are August and October (43%).
Average rainfall in September
Castaic, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is December (1.42").
The driest months (with the least rainfall) are June and August (0.04").
Average rainfall days in September
Castaic, CA
- Average rainfall days in September: 2.3 days
The month with the highest number of rainy days is March (6.9 days).
The month with the least rainy days is June (0.7 days).
Average daylight in September /
Average sunshine in September
Castaic, CA
- Average daylight in September: 12h and 2min
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 5min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The month with the least sunshine is February (Average sunshine: 6h and 42min).
Average sunshine days in September
Castaic, CA
- Average sunshine days in September: 27 days
The month with the most sunshine days is August (28.7 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in September
Castaic, 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
Castaic, CA
- Average cloud cover in September: 6
The month with the most cloud cover is March (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 4).
Average visibility in September
Castaic, 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).
Castaic, California, USA
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