September weather forecastSouth San Jose Hills, CA
September
Weather in September
The first month of the autumn, September, is still a hot month in South San Jose Hills, California, with an average temperature varying between 64.8°F (18.2°C) and 86°F (30°C).Temperature
September's presence marks an average high-temperature of a still tropical 86°F (30°C), subtly varied from August's 88.3°F (31.3°C). In South San Jose Hills, the September nights cool down to an average low of 64.8°F (18.2°C).Heat index
September's average heat index is estimated at a hot 87.8°F (31°C). Exhaustion is likely with prolonged exposure and activity. Sustaining activity may result in heat cramps.Given the heat index, its values are aligned with shaded sites and gentle winds. If exposed to direct sunlight, the heat index could climb by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'real feel', integrates the air's temperature and its humidity to showcase the felt temperature by people. This effect tends to be personal, with the weather perception differing among individuals due to variations in body mass, height, and exertion. Being under direct sunshine can magnify the heat experience, possibly pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular importance for children. Kids are generally in more danger than adults because they perspire less. Their large skin surface area compared to their small bodies and the excessive heat due to their actions raises their risk.
Humidity
In South San Jose Hills, the average relative humidity in September is 51%.Rainfall
In South San Jose Hills, in September, it is raining for 2.1 days, with typically 0.08" (2mm) of accumulated precipitation. In South San Jose Hills, during the entire year, the rain falls for 43.8 days and collects up to 7.01" (178mm) of precipitation.Daylight
In South San Jose Hills, the average length of the day in September is 12h and 22min.On the first day of September in South San Jose Hills, sunrise is at 6:25 am and sunset at 7:16 pm. On the last day of the month, sunrise is at 6:45 am and sunset at 6:36 pm PDT.
Sunshine
In September, the average sunshine is 10.6h.UV index
In September, the average daily maximum UV index is 6. A UV Index estimate of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for the average person.Note: In September, the UV index of 6 transforms into the following advice:
Adopt measures and apply sun safety strategies. Shielding from skin and eye damage is necessary. Limit direct sun exposure and seek shade between 10 a.m. and 4 p.m., the time of the most intense UV radiation, noting that shade structures may not provide total sun protection. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
South San Jose Hills, CA
- Average high temperature in September: 86°F
The warmest month (with the highest average high temperature) is August (88.3°F).
The month with the lowest average high temperature is December (64.9°F).
- Average low temperature in September: 64.8°F
The month with the highest average low temperature is August (66.2°F).
The coldest month (with the lowest average low temperature) is February (48.9°F).
Average pressure in September
South San Jose Hills, CA
- Average pressure in September: 29.89"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
South San Jose Hills, CA
- Average wind speed in September: 4.6mph
The windiest month (with the highest average wind speed) is April (5.8mph).
The calmest month (with the lowest average wind speed) is September (4.6mph).
Average humidity in September
South San Jose Hills, CA
- Average humidity in September: 51%
The month with the highest relative humidity is June (59%).
The month with the lowest relative humidity is November (46%).
Average rainfall in September
South San Jose Hills, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is December (1.61").
The driest months (with the least rainfall) are June and August (0.04").
Average rainfall days in September
South San Jose Hills, CA
- Average rainfall days in September: 2.1 days
The month with the highest number of rainy days is March (6.6 days).
The month with the least rainy days is June (1.1 days).
Average daylight in September /
Average sunshine in September
South San Jose Hills, 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 36min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The months with the least sunshine are February and December (Average sunshine: 6h and 48min).
Average sunshine days in September
South San Jose Hills, CA
- Average sunshine days in September: 26.1 days
The month with the most sunshine days is August (28.2 days).
The month with the least sunshine days is February (21.6 days).
Average UV index in September
South San Jose Hills, CA
- Average UV index in September: 6
The month with the highest UV index is August (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 4).
Average cloud cover in September
South San Jose Hills, CA
- Average cloud cover in September: 8
The months with the most cloud cover are March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in September
South San Jose Hills, 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).
