September weather forecastBlackhawk, CA
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Blackhawk, California, with an average temperature fluctuating between 82°F (27.8°C) and 56.5°F (13.6°C).Temperature
September's onset brings an average high-temperature of a still warm 82°F (27.8°C), showing a minute difference from August's 83.3°F (28.5°C). Blackhawk experiences a substantial decline from the daytime high temperatures in September, settling on an average low of 56.5°F (13.6°C).Heat index
The heat index for September is estimated at 84.2°F (29°C). Persisting in activity during exposure could lead to weariness and subsequently to heat cramps.It is important to note that the heat index values are for shaded areas and light wind scenarios. Exposing to direct sunshine may enhance heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', is what the temperature feels like to the human body when the air temperature is combined with the relative humidity. The individual's impression of temperature can be shaped by additional aspects such as metabolic variations, physical activity, and clothing. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely vital to babies and toddlers. Kids are usually more vulnerable than adults, given their lesser sweating ability. Along with their larger skin surface relative to their small stature and the excess heat due to their activity, their risk is amplified.
Humidity
The least humid month is September, with an average relative humidity of 57%.Rainfall
In September, the rain falls for 1.8 days. Throughout September, 0.08" (2mm) of precipitation is accumulated. In Blackhawk, during the entire year, the rain falls for 67.2 days and collects up to 10.98" (279mm) of precipitation.Daylight
In Blackhawk, the average length of the day in September is 12h and 25min.On the first day of the month, sunrise is at 6:38 am and sunset at 7:36 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:51 pm PDT.
Sunshine
In Blackhawk, the average sunshine in September is 11.2h.UV index
The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index, 5 during September, leads to the following recommendations:
Undertake protective steps - Preventing sun damage is advised. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Blackhawk, CA
- Average high temperature in September: 82°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 (55.9°F).
- Average low temperature in September: 56.5°F
The month with the highest average low temperature is September (56.5°F).
The coldest month (with the lowest average low temperature) is December (42.1°F).
Average pressure in September
Blackhawk, 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
Blackhawk, CA
- Average wind speed in September: 5.2mph
The windiest month (with the highest average wind speed) is May (6.7mph).
The calmest month (with the lowest average wind speed) is November (4.2mph).
Average humidity in September
Blackhawk, 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
Blackhawk, CA
- Average rainfall in September: 0.08"
The wettest month (with the highest rainfall) is February (2.28").
The driest month (with the least rainfall) is July (0").
Average rainfall days in September
Blackhawk, CA
- Average rainfall days in September: 1.8 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
Blackhawk, CA
- Average daylight in September: 12h and 24min
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 12min
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
Blackhawk, CA
- Average sunshine days in September: 27.5 days
The month with the most sunshine days is July (29.9 days).
The month with the least sunshine days is March (17.5 days).
Average UV index in September
Blackhawk, 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
Blackhawk, 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
Blackhawk, 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).
