September weather forecast
Angwin, CA

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Weather in September

The first month of the autumn, September, is still a warm month in Angwin, California, with an average temperature ranging between min 54.3°F (12.4°C) and max 85.3°F (29.6°C).

Temperature

September records an average high-temperature of a moderately hot 85.3°F (29.6°C), indicating a minor variation from the preceding month. From significant daily highs, Angwin's nights in September cool down to an average low-temperature of 54.3°F (12.4°C).

Heat index

The heat index in September is calculated to be a hot 87.8°F (31°C). Enduring exposure and unrelenting activity might cause a state of weariness, potentially leading to heat cramps.
In the scope of the heat index, its values resonate with shade and light wind conditions. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', is a value derived by merging air temperature with the humidity to convey how the climate feels. Additional elements encompassing metabolic differences, the degree of physical activity, and attire can impact the individual's perception of temperature. It is noteworthy that being in direct sunlight can enhance the weather's impact, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical for babies and toddlers. In general, children are more at risk than adults because they sweat less. Furthermore, the large skin surface compared to their small bodies and the high heat production due to their actions contribute to this vulnerability.

Humidity

September is the least humid month in Angwin, with an average relative humidity of 53%.

Rainfall

In Angwin, in September, during 2 rainfall days, 0.08" (2mm) of precipitation is typically accumulated. Throughout the year, in Angwin, there are 76.2 rainfall days, and 16.93" (430mm) of precipitation is accumulated.

Snowfall

In Angwin, snow does not fall in January, February, April through December.

Daylight

In September, the average length of the day is 12h and 25min.
On the first day of the month, sunrise is at 6:39 am and sunset at 7:39 pm. On the last day of September, sunrise is at 7:05 am and sunset at 6:53 pm PDT.

Sunshine

In September, the average sunshine in Angwin is 11h.

UV index

In September, the average daily maximum UV index is 5. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for ordinary individuals.
Note: A daily high UV index of 5 in September leads to these guidelines:
Make use of precautions - Shielding skin and eyes from injury is a requirement. Limiting sun exposure during midday hours helps in reducing the harmful effects of UV radiation. Experience reduced UV exposure by about half when donning a wide-brim hat.
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Frequently asked questions

How hot is it in Angwin in September?

The average high-temperature and low-temperature in Angwin during September are 85.3°F (29.6°C) and 54.3°F (12.4°C) respectively. In September, the average heat index (a.k.a. 'felt air temperature', 'feels like'), which represents the influence of relative humidity on air temperature, is calculated to be 87.8°F (31°C).

What is the least humid month in Angwin?

With an average relative humidity of 53%, September is the least humid month.

What is the average humidity in September in Angwin?

In September, the average relative humidity in Angwin is 53%.

How many days does it rain in September in Angwin?

In Angwin, in September, during 2 rainfall days, 0.08" (2mm) of precipitation is typically accumulated.

When it does not snow in Angwin?

January, February, April through December are months without snowfall.

How many hours of daylight does Angwin have in September?

In Angwin, the average day length in September is 12h and 25min.

When are sunrise and sunset in September in Angwin?

On the first day of September in Angwin, California, sunrise is at 6:39 am and sunset at 7:39 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:53 pm PDT.

How many hours of sunshine does Angwin have in September?

In Angwin, California, the average sunshine duration in September is 11h.

What is the UV index intensity in September in Angwin?

The average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium hazard to health from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Angwin, CA

Average temperature in September - Angwin, CA
  • Average high temperature in September: 85.3°F

The warmest month (with the highest average high temperature) is July (88.3°F).
The month with the lowest average high temperature is December (54.5°F).

  • Average low temperature in September: 54.3°F

The month with the highest average low temperature is September (54.3°F).
The coldest month (with the lowest average low temperature) is December (39.6°F).

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Average pressure in September
Angwin, CA

Average pressure in September - Angwin, CA
  • Average pressure in September: 29.91"Hg

The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.91"Hg).

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Average wind speed in September
Angwin, CA

Average wind speed in September - Angwin, CA
  • Average wind speed in September: 4.6mph

The windiest month (with the highest average wind speed) is May (5.8mph).
The calmest month (with the lowest average wind speed) is November (4.3mph).

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Average humidity in September
Angwin, CA

Average humidity in September - Angwin, CA
  • Average humidity in September: 53%

The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is September (53%).

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Average rainfall in September
Angwin, CA

Average rainfall in September - Angwin, CA
  • Average rainfall in September: 0.08"

The wettest month (with the highest rainfall) is February (3.7").
The driest month (with the least rainfall) is July (0").

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Average rainfall days in September
Angwin, CA

Average rainfall days in September - Angwin, CA
  • Average rainfall days in September: 2 days

The month with the highest number of rainy days is March (13.5 days).
The month with the least rainy days is August (0.3 days).

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Average snowfall in September
Angwin, CA

Average snowfall in September - Angwin, CA
  • Average snowfall in September: 0"

The month with the highest snowfall is March (0.04").
The months with the least snowfall are January, February, April, May, June, July, August, September, October, November and December (0").

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Average snowfall days in September
Angwin, CA

Average snowfall days in September - Angwin, CA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is March (0.2 days).
The months with the least snowfall days are January, February, April, May, June, July, August, September, October, November and December (0 days).

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Average daylight in September /
Average sunshine in September
Angwin, CA

Average daylight in September / Average sunshine in September - Angwin, CA
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in September: 11h and 0min

The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 18min).

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Average sunshine days in September
Angwin, CA

Average sunshine days in September - Angwin, CA
  • Average sunshine days in September: 27.5 days

The month with the most sunshine days is July (30 days).
The month with the least sunshine days is March (15.9 days).

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Average UV index in September
Angwin, CA

Average UV index in September - Angwin, 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 January, February, November and December (UV index 3).

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Average cloud cover in September
Angwin, CA

Average cloud cover in September - Angwin, CA
  • Average cloud cover in September: 10

The month with the most cloud cover is March (Cloud cover 44).
The month with the least cloud cover is July (Cloud cover 7).

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Average visibility in September
Angwin, CA

Average visibility in September - Angwin, CA
  • Average visibility in September: 6mi

The months with the highest visibility are February, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and March (5mi).

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Angwin, California, USA

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