September weather forecast and climate
South San Jose Hills, CA

Weather in September

The first month of the autumn, September, is still a tropical month in South San Jose Hills, California, with average temperature fluctuating between 86°F (30°C) and 64.8°F (18.2°C).

Temperature

In South San Jose Hills, California, the average high-temperature in September is almost the same as in August - a still hot 86°F (30°C). The average low-temperature, in September, is 64.8°F (18.2°C).

Heat index

The average heat index is appraised at a hot 88.2°F (31.2°C). Exhaustion is likely with prolonged exposure and activity. Sustaining activity may result in heat cramps.
Note that heat index values are valued for light wind and location in the shade. Exposure to direct sunshine can increase heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel', 'apparent temperature', 'feels like', or 'felt air temperature', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. This effect is subjective, depending on the activity and individual's heat perception influenced by various reasons (metabolic differences, clothing, wind). Be aware that direct exposure to sunlight increases heat impact, and may raise the heat index additionally, by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.

Humidity

In South San Jose Hills, the average relative humidity is 51%.

Rainfall

In South San Jose Hills, 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

The average length of the day in South San Jose Hills is 12.4h.

Sunshine

In South San Jose Hills, the average sunshine is 10.6h.

UV index

In South San Jose Hills, the average daily maximum UV index is 6. A UV Index estimate of 6 to 7 represents a high health risk from the exposure to the Sun's UV rays for ordinary individuals.
Note: In September, the average maximum UV index of 6 translate into the following recommendations:
Take precautions and utilize sun safety practices. Protection against the skin and eye damage is required. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun.
[Resources]

FAQ

What is the temperature in September in South San Jose Hills?

The average high-temperature, in September, in South San Jose Hills, is 86°F (30°C), while the average low-temperature is 64.8°F (18.2°C). In September, the average heat index (a.k.a. 'real feel', 'apparent temperature'), that factores the actual air temperature with the relative humidity, is appraised at 88.2°F (31.2°C).

What is the average humidity in September in South San Jose Hills?

The average relative humidity in September in South San Jose Hills is 51%.

How many days does it rain in September in South San Jose Hills?

In South San Jose Hills, California, in September, during 2.1 rainfall days, 0.08" (2mm) of precipitation is typically accumulated.

How many hours of daylight does South San Jose Hills have in September?

In South San Jose Hills, the average length of the day in September is 12.4h.

How long on average sun shines in September in South San Jose Hills?

In September, the average sunshine in South San Jose Hills, California, is 10.6h.

What is the UV index reading in September in South San Jose Hills?

In September, the average daily maximum UV index is 6. A UV Index of 6 to 7 symbolizes a high health vulnerability from unprotected exposure to the UV radiation.

Average temperature in September
South San Jose Hills, CA

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).

[Resources]

Average pressure in September
South San Jose Hills, CA

Average pressure in September - South San Jose Hills, CA
  • Average pressure in September: 29.89"

The month with the highest atmospheric pressure is January (30.1").
The month with the lowest atmospheric pressure is June (29.88").

[Resources]

Average wind speed in September
South San Jose Hills, CA

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).

[Resources]

Average humidity in September
South San Jose Hills, CA

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%).

[Resources]

Average rainfall in September
South San Jose Hills, CA

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").

[Resources]

Average rainfall days in September
South San Jose Hills, CA

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).

[Resources]

Average daylight in September /
Average sunshine in September
South San Jose Hills, CA

Average daylight in September / Average sunshine in September - South San Jose Hills, CA
  • Average daylight in September: 12.4h

The month with the longest days is June (Average daylight: 14.4h).
The month with the shortest days is December (Average daylight: 9.9h).

  • Average sunshine in September: 10.6h

The month with the most sunshine is July (Average sunshine: 12.1h).
Months with the least sunshine are February and December (Average sunshine: 6.8).

[Resources]

Average sunshine days in September
South San Jose Hills, CA

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).

[Resources]

Average UV index in September
South San Jose Hills, CA

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).
Months with the lowest UV index are January, February, November and December (UV index 4).

[Resources]

Average cloud cover in September
South San Jose Hills, CA

Average cloud cover in September - South San Jose Hills, CA
  • Average cloud cover in September: 8

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).

[Resources]

Average visibility in September
South San Jose Hills, CA

Average visibility in September - South San Jose Hills, CA
  • Average visibility in September: 6mi

Months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
Months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

[Resources]