September weather forecastSan Fernando, CA
September
Weather in September
September, the first month of the autumn in San Fernando, is still a warm month, with temperature in the range of an average high of 83.1°F (28.4°C) and an average low of 62.6°F (17°C).Temperature
The transition into September notes an average high-temperature of a still moderately hot 83.1°F (28.4°C), revealing a mild distinction from the 85.8°F (29.9°C) in August. During the month of September, an average temperature of 62.6°F (17°C) is noted during the nights.Heat index
The heat index value for September is computed to be 84.2°F (29°C). Exposure and extended activity could potentially cause a state of fatigue and lead to heat cramps.Take into consideration that the heat index values are calculated for shade and light wind conditions. Exposing to direct sunshine may enhance heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', offers an insight into how hot it feels when we factor in moisture content. Elements such as metabolic variations, pregnancy, and physical exertion can shape one's weather perception. When in direct sunlight, one should be cautious as it can raise the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Youths are typically more endangered than adults since they usually sweat less. Their larger skin surface concerning their smaller bodies and higher heat production due to activity further adds to their vulnerability.
Humidity
The average relative humidity in September is 51%.Rainfall
In San Fernando, in September, during 2.6 rainfall days, 0.12" (3mm) of precipitation is typically accumulated. Throughout the year, there are 39.8 rainfall days, and 7.52" (191mm) of precipitation is accumulated.Daylight
In San Fernando, the average length of the day in September is 12h and 22min.On the first day of the month, sunrise is at 6:27 am and sunset at 7:19 pm. On the last day of September, sunrise is at 6:48 am and sunset at 6:38 pm PDT.
Sunshine
The average sunshine in September in San Fernando is 10.8h.UV index
The months with the highest UV index are June through September, with an average maximum UV index of 6. 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: In September, a daily UV index of 6 turns into the following recommendations:
Enforce precautions and stick to sun safety measures. Preservation from skin and eye damage is essential. Avoid direct Sun exposure and seek shade between 10 a.m. and 4 p.m., when UV radiation is at its peak, but keep in mind that not all shade structures provide complete protection. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
San Fernando, CA
- Average high temperature in September: 83.1°F
The warmest month (with the highest average high temperature) is August (85.8°F).
The month with the lowest average high temperature is December (61.7°F).
- Average low temperature in September: 62.6°F
The month with the highest average low temperature is August (64.9°F).
The coldest month (with the lowest average low temperature) is December (46.2°F).
Average pressure in September
San Fernando, 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 (29.89"Hg).
Average wind speed in September
San Fernando, CA
- Average wind speed in September: 4.5mph
The windiest months (with the highest average wind speed) are January and December (6.2mph).
The calmest month (with the lowest average wind speed) is September (4.5mph).
Average humidity in September
San Fernando, CA
- Average humidity in September: 51%
The month with the highest relative humidity is June (58%).
The month with the lowest relative humidity is November (47%).
Average rainfall in September
San Fernando, CA
- Average rainfall in September: 0.12"
The wettest month (with the highest rainfall) is February (1.54").
The driest month (with the least rainfall) is June (0").
Average rainfall days in September
San Fernando, CA
- Average rainfall days in September: 2.6 days
The month with the highest number of rainy days is March (6.3 days).
The month with the least rainy days is June (0.8 days).
Average daylight in September /
Average sunshine in September
San Fernando, CA
- Average daylight in September: 12h and 24min
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 48min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The months with the least sunshine are January, February and December (Average sunshine: 6h and 48min).
Average sunshine days in September
San Fernando, CA
- Average sunshine days in September: 26.7 days
The month with the most sunshine days is May (28.8 days).
The month with the least sunshine days is February (22.9 days).
Average UV index in September
San Fernando, CA
- Average UV index in September: 6
The months with the highest UV index are June, July, August and September (UV index 6).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
San Fernando, CA
- Average cloud cover in September: 7
The month with the most cloud cover is March (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 4).
Average visibility in September
San Fernando, 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).
