September weather forecastPleasant Hill, CA
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Pleasant Hill, California, with an average temperature fluctuating between 57.4°F (14.1°C) and 81.9°F (27.7°C).Temperature
Pleasant Hill, California, measures an average high-temperature of a still moderately hot 81.9°F (27.7°C) in September, nearly consistent with the preceding month. Despite substantial daily fluctuations, the average low-temperature in Pleasant Hill is a mild 57.4°F (14.1°C) during September.Heat index
The heat index in September is evaluated at 84.2°F (29°C). Unrelenting activity during exposure could cause fatigue and potentially lead to heat cramps.In reference to the heat index, it's for places in shade and with a slight wind. Exposure to the direct sun could elevate the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'apparent temperature', is a calculation that merges air temperature and relative humidity to depict the sensation of warmth. Elements such as metabolic variations, being pregnant, and physical activity can impact one's weather perception. One must note that being under the direct sun can escalate the heat's effects, with the heat index possibly rising by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
Humidity
The least humid month in Pleasant Hill is September, with an average relative humidity of 56%.Rainfall
June through September are months with the least rain when the rain falls for 1.8 days and typically aggregates up to 0.04" (1mm) of rain.Daylight
In September, the average length of the day is 12h and 25min.On the first day of September, sunrise is at 6:38 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:03 am and sunset at 6:52 pm PDT.
Sunshine
In Pleasant Hill, the average sunshine in September is 11h.UV index
In September, the average daily maximum UV index in Pleasant Hill is 5. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for the average person.Note: In September, the average maximum UV index of 5 translates into the following recommendations:
Adopt protective measures - Requirement to safeguard skin and eyes from harm exists. Avoid the Sun's strongest UV rays by seeking shade and limiting exposure during midday. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Pleasant Hill, CA
- Average high temperature in September: 81.9°F
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in September: 57.4°F
The month with the highest average low temperature is September (57.4°F).
The coldest month (with the lowest average low temperature) is January (42.3°F).
Average pressure in September
Pleasant Hill, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in September
Pleasant Hill, CA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is May (7.6mph).
The calmest month (with the lowest average wind speed) is November (4.5mph).
Average humidity in September
Pleasant Hill, CA
- Average humidity in September: 56%
The months with the highest relative humidity are January and March (73%).
The month with the lowest relative humidity is September (56%).
Average rainfall in September
Pleasant Hill, CA
- Average rainfall in September: 0.04"
The wettest month (with the highest rainfall) is February (0.87").
The driest months (with the least rainfall) are June, July, August and September (0.04").
Average rainfall days in September
Pleasant Hill, CA
- Average rainfall days in September: 1.8 days
The month with the highest number of rainy days is March (9.8 days).
The month with the least rainy days is August (0.5 days).
Average daylight in September /
Average sunshine in September
Pleasant Hill, CA
- Average daylight in September: 12h and 24min
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 36min).
- Average sunshine in September: 11h and 0min
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 42min).
Average sunshine days in September
Pleasant Hill, CA
- Average sunshine days in September: 27.8 days
The month with the most sunshine days is July (29.5 days).
The month with the least sunshine days is March (20 days).
Average UV index in September
Pleasant Hill, CA
- Average UV index in September: 5
The months with the highest UV index are June and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Pleasant Hill, CA
- Average cloud cover in September: 11
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 8).
Average visibility in September
Pleasant Hill, 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).
