September weather forecast
Crest, CA

Share

Weather in September

September, the first month of the autumn in Crest, is also a moderately hot month, with an average temperature varying between 83.3°F (28.5°C) and 63.5°F (17.5°C).

Temperature

Crest's average high-temperature in September is a still moderately hot 83.3°F (28.5°C), indicating a subtle variation from August. The temperature dips to an average of 63.5°F (17.5°C) during September nights.

Heat index

The heat index in September is computed to be a hot 86°F (30°C). A sense of exhaustion might occur with extended exposure and activity, potentially causing heat cramps.
Evaluating the heat index requires understanding its values in the shade and with gentle winds. Direct sunlight exposure may cause a 15 Fahrenheit (8 Celsius) degrees rise in the heat index.
Note: The heat index, also known as 'feels like' or 'felt air temperature', gives an indication of how one might feel in terms of heat after considering humidity. Factors including metabolic differences, physical activity, and clothing are additional elements that influence the individual's temperature experience. It is important to note that direct sunlight can intensify the weather impact, potentially raising the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital for babies and toddlers. Youngsters generally face more threats than adults given their lesser ability to sweat. Coupled with their larger skin surface relative to their small bodies and higher heat production due to their activities, they are more endangered.

Humidity

In September, the average relative humidity is 57%.

Rainfall

In September, in Crest, the rain falls for 3.9 days. Throughout September, 0.31" (8mm) of precipitation is accumulated. In Crest, during the entire year, the rain falls for 49.6 days and collects up to 5.16" (131mm) of precipitation.

Daylight

In September, the average length of the day is 12h and 22min.
On the first day of September, sunrise is at 6:22 am and sunset at 7:11 pm. On the last day of the month, sunrise is at 6:41 am and sunset at 6:32 pm PDT.

Sunshine

In September, the average sunshine is 10.4h.

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 vulnerability from exposure to the Sun's UV radiation for the ordinary person.
Note: In September, an average UV index of 6 transforms into the following instructions:
Prevent overexposure. Protection from the sun's harmful effects is needed. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Updated: Jul 26, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How hot is September?

In September, in Crest, the average high-temperature is 83.3°F (28.5°C), and the average low-temperature is 63.5°F (17.5°C). The average heat index (a.k.a. 'felt air temperature', 'apparent temperature'), which represents the influence of relative humidity on air temperature, in September is computed to be 86°F (30°C).

What is the average humidity in September?

In September, the average relative humidity is 57%.

How many days does it rain in September?

In Crest, in September, during 3.9 rainfall days, 0.31" (8mm) of precipitation is typically accumulated.

How many hours of daylight does Crest have in September?

In September, the average day length is 12h and 22min.

When is the sunrise / sunset in September?

On the first day of September, sunrise is at 6:22 am and sunset at 7:11 pm. On the last day of the month, sunrise is at 6:41 am and sunset at 6:32 pm PDT.

How many hours of sunshine does Crest have in September?

In September, the average sunshine duration is 10.4h.

What are the months with the highest UV index?

June through September, with an average maximum UV index of 6, are months with the highest UV index in Crest.

How high is the UV index in September?

The average daily maximum UV index in September is 6. A UV Index reading of 6 to 7 represents a high health risk from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Crest, CA

Average temperature in September - Crest, CA
  • Average high temperature in September: 83.3°F

The warmest month (with the highest average high temperature) is August (85.5°F).
The month with the lowest average high temperature is December (63.7°F).

  • Average low temperature in September: 63.5°F

The month with the highest average low temperature is August (64.9°F).
The coldest month (with the lowest average low temperature) is February (46°F).

Average pressure in September
Crest, CA

Average pressure in September - Crest, CA
  • Average pressure in September: 29.87"Hg

The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).

Average wind speed in September
Crest, CA

Average wind speed in September - Crest, CA
  • Average wind speed in September: 4.2mph

The windiest months (with the highest average wind speed) are April and May (5.3mph).
The calmest months (with the lowest average wind speed) are August, September and October (4.2mph).

Average humidity in September
Crest, CA

Average humidity in September - Crest, CA
  • Average humidity in September: 57%

The month with the highest relative humidity is May (65%).
The month with the lowest relative humidity is November (52%).

Average rainfall in September
Crest, CA

Average rainfall in September - Crest, CA
  • Average rainfall in September: 0.31"

The wettest month (with the highest rainfall) is February (1.06").
The driest month (with the least rainfall) is June (0.04").

Average rainfall days in September
Crest, CA

Average rainfall days in September - Crest, CA
  • Average rainfall days in September: 3.9 days

The month with the highest number of rainy days is March (6.8 days).
The month with the least rainy days is June (1.4 days).

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

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

The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).

  • Average sunshine in September: 10h and 2min

The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).

Average sunshine days in September
Crest, CA

Average sunshine days in September - Crest, CA
  • Average sunshine days in September: 23.1 days

The month with the most sunshine days is June (28 days).
The month with the least sunshine days is July (20.7 days).

Average UV index in September
Crest, CA

Average UV index in September - Crest, 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
Crest, CA

Average cloud cover in September - Crest, CA
  • Average cloud cover in September: 9

The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 6).

Average visibility in September
Crest, CA

Average visibility in September - Crest, 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).

Crest, California, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location