Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
Diablo's average high-temperature marks a still moderately hot 82°F with the advent of September, closely mirroring that of the preceding month. Diablo reports a substantial plunge from daytime highs during the nights of September, with an average low-temperature of 56.7°F.Heat index
September's mean heat index is estimated at 84.2°F. Fatigue might occur with continuous exposure and activity, potentially causing heat cramps.Records show heat index calculations are tailored for shaded regions and mild winds. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', gives a temperature feeling by integrating air temperature and humidity. The influence of weather is personal, with varied individuals experiencing it differently due to differences in body mass, stature, and physical exertion levels. Awareness is key; direct sunlight can enhance the weather's impact, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular importance for children. Children often fail to recognize the requirement to rest and rehydrate. Thirst, being a late symptom of dehydration, underlines the importance of maintaining hydration, especially during ongoing physical activities.
Humidity
September is the least humid month, with an average relative humidity of 57%.Rainfall
January through June, September through December are months with rainfall in Diablo. September is the first month it rains. Throughout September, in the average 1.7 rainfall days, it receives 0.08" of precipitation. In Diablo, during the entire year, the rain falls for 65.6 days and collects up to 11.22" of precipitation.Daylight
In September, the average length of the day in Diablo is 12h and 25min.On the first day of the month, sunrise is at 6:37 am and sunset at 7:37 pm. On the last day of September, sunrise is at 7:02 am and sunset at 6:52 pm PDT.
Sunshine
The average sunshine in September is 11.1h.UV index
In September, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for average individuals.Note: A maximum high daily UV index of 5 during September translates into the following directions:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. To mitigate harm from sun exposure, pick sunglasses offering UVA and UVB defense.
FAQ
What are the temperatures in Diablo in September?
What is the least humid month in Diablo?
What is the average humidity in September in Diablo?
When does it start to rain in Diablo?
How many hours of daylight does Diablo have in September?
When are sunrise and sunset in September in Diablo?
How long on average sun shines in September in Diablo?
What is the UV index intensity in September in Diablo?
Average temperature in September
Diablo, CA
- Average high temperature in September: 82°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is December (55.8°F).
- Average low temperature in September: 56.7°F
The months with the highest average low temperature are August and September (56.7°F).
The coldest month (with the lowest average low temperature) is January (42.1°F).
Average pressure in September
Diablo, CA
- Average pressure in September: 29.92"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 (29.92"Hg).
Average wind speed in September
Diablo, CA
- Average wind speed in September: 5.4mph
The windiest month (with the highest average wind speed) is May (6.9mph).
The calmest month (with the lowest average wind speed) is November (4.3mph).
Average humidity in September
Diablo, CA
- Average humidity in September: 57%
The month with the highest relative humidity is March (74%).
The month with the lowest relative humidity is September (57%).
Average rainfall in September
Diablo, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is February (2.36").
The driest months (with the least rainfall) are July and August (0").
Average rainfall days in September
Diablo, CA
- Average rainfall days in September: 1.7 days
The month with the highest number of rainy days is March (12.6 days).
The month with the least rainy days is August (0.6 days).
Average daylight in September /
Average sunshine in September
Diablo, CA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 11h and 1min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in September
Diablo, CA
- Average sunshine days in September: 27.2 days
The month with the most sunshine days is July (30.2 days).
The month with the least sunshine days is March (17.6 days).
Average UV index in September
Diablo, 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).
Average cloud cover in September
Diablo, CA
- Average cloud cover in September: 10
The month with the most cloud cover is March (Cloud cover 36).
The month with the least cloud cover is July (Cloud cover 6).
Average visibility in September
Diablo, 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).
Diablo, California, USA
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