September weather forecast
Redwood Valley, CA

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Weather in September

The first month of the autumn, September, is also a moderately hot month in Redwood Valley, California, with an average temperature fluctuating between 80.8°F (27.1°C) and 51.4°F (10.8°C).

Temperature

Redwood Valley registers an average high-temperature of a still warm 80.8°F (27.1°C) at the commencement of September, closely related to the preceding month. A noticeable downturn in temperature characterizes the September nights, averaging at a fresh 51.4°F (10.8°C).

Heat index

The heat index in September is evaluated at 82.4°F (28°C). Enduring exposure and unrelenting activity might cause a state of weariness, potentially leading to heat cramps.
It is crucial to understand that heat index figures are for shade and gentle wind conditions. The heat index values could be amplified by up to 15 Fahrenheit (8 Celsius) degrees in direct sunlight.
Note: The heat index, also known as 'real feel' or 'felt air temperature', combines both the air temperature and the humidity level to give a perceived human temperature. One's perception of temperature is subjective, varying based on their activity and individual heat perception, influenced by factors like wind, clothing, and metabolic variations. With the sun shining directly, it's crucial to understand that it can increase the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially vital to children. Juveniles often do not understand the need to recuperate and rehydrate. Thirst is a delayed symptom of dehydration - hence, it is vital to maintain hydration, particularly during ongoing physical activities.

Humidity

July and September, with an average relative humidity of 58%, are the least humid months.

Rainfall

In September, the rain falls for 2.5 days. Throughout September, 0.2" (5mm) of precipitation is accumulated. Throughout the year, there are 83.3 rainfall days, and 17.72" (450mm) of precipitation is accumulated.

Snowfall

In Redwood Valley, snow does not fall in January, March through December.

Daylight

In Redwood Valley, the average length of the day in September is 12h and 26min.
On the first day of the month, sunrise is at 6:42 am and sunset at 7:42 pm. On the last day of September, sunrise is at 7:08 am and sunset at 6:56 pm PDT.

Sunshine

In September, the average sunshine is 10.9h.

UV index

In September, the average daily maximum UV index in Redwood Valley is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV radiation for the average person.
Note: In September, a daily UV index of 4 turns into the following recommendations:
Exercise care. People with light skin might get burns in fewer than 30 minutes. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Updated: Aug 14, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the usual temperature for Redwood Valley in September?

The average high-temperature and low-temperature during September are 80.8°F (27.1°C) and 51.4°F (10.8°C) respectively. The average heat index (a.k.a. 'felt air temperature', 'real feel'), which combines air temperature and relative humidity, in September is evaluated at 82.4°F (28°C).

What are the least humid months?

The months with the lowest humidity are July and September, with an average relative humidity of 58%.

What is the average humidity in September?

The average relative humidity in September is 58%.

How many days does it rain in September?

In Redwood Valley, in September, it is raining for 2.5 days, with typically 0.2" (5mm) of accumulated precipitation.

When it does not snow in Redwood Valley?

January, March through December are months without snowfall.

What is the average length of the day in September?

The average day length in September is 12h and 26min.

When are sunrise and sunset in September?

On the first day of September, sunrise is at 6:42 am and sunset at 7:42 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 6:56 pm PDT.

How many hours of sunshine does Redwood Valley have in September?

In September, the average sunshine duration is 10.9h.

How high is the UV index in September?

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium health risk from unsafe exposure to Sun's UV rays.
Average max. wind speed
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
Redwood Valley, CA

Average temperature in September - Redwood Valley, CA
  • Average high temperature in September: 80.8°F

The warmest month (with the highest average high temperature) is July (85.3°F).
The month with the lowest average high temperature is December (53.6°F).

  • Average low temperature in September: 51.4°F

The month with the highest average low temperature is July (53.6°F).
The coldest month (with the lowest average low temperature) is December (37.4°F).

Average pressure in September
Redwood Valley, CA

Average pressure in September - Redwood Valley, CA
  • Average pressure in September: 29.92"Hg

The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).

Average wind speed in September
Redwood Valley, CA

Average wind speed in September - Redwood Valley, CA
  • Average wind speed in September: 4.4mph

The windiest months (with the highest average wind speed) are April, May and June (5.5mph).
The calmest month (with the lowest average wind speed) is November (4.2mph).

Average humidity in September
Redwood Valley, CA

Average humidity in September - Redwood Valley, CA
  • Average humidity in September: 58%

The month with the highest relative humidity is March (79%).
The months with the lowest relative humidity are July and September (58%).

Average rainfall in September
Redwood Valley, CA

Average rainfall in September - Redwood Valley, CA
  • Average rainfall in September: 0.2"

The wettest months (with the highest rainfall) are February and December (3.11").
The driest months (with the least rainfall) are July and August (0.08").

Average rainfall days in September
Redwood Valley, CA

Average rainfall days in September - Redwood Valley, CA
  • Average rainfall days in September: 2.5 days

The month with the highest number of rainy days is March (14.3 days).
The month with the least rainy days is August (1.3 days).

Average snowfall in September
Redwood Valley, CA

Average snowfall in September - Redwood Valley, CA
  • Average snowfall in September: 0"

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

Average snowfall days in September
Redwood Valley, CA

Average snowfall days in September - Redwood Valley, CA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (0.3 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October, November and December (0 days).

Average daylight in September /
Average sunshine in September
Redwood Valley, CA

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

The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in September: 10h and 5min

The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 18min).

Average sunshine days in September
Redwood Valley, CA

Average sunshine days in September - Redwood Valley, CA
  • Average sunshine days in September: 26.9 days

The month with the most sunshine days is July (28.5 days).
The month with the least sunshine days is March (15.9 days).

Average UV index in September
Redwood Valley, CA

Average UV index in September - Redwood Valley, CA
  • Average UV index in September: 4

The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are February and November (UV index 2).

Average cloud cover in September
Redwood Valley, CA

Average cloud cover in September - Redwood Valley, CA
  • Average cloud cover in September: 11

The month with the most cloud cover is March (Cloud cover 45).
The month with the least cloud cover is August (Cloud cover 6).

Average visibility in September
Redwood Valley, CA

Average visibility in September - Redwood Valley, CA
  • Average visibility in September: 6mi

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

Redwood Valley, California, USA

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