September weather forecastGranite Bay, CA
September
Weather in September
The first month of the autumn, September, is still a hot month in Granite Bay, California, with temperature in the range of an average low of 58.1°F (14.5°C) and an average high of 86.9°F (30.5°C).Temperature
As Granite Bay steps into September, the average high-temperature is measured at a still hot 86.9°F (30.5°C), displaying minor differences from August's 92.1°F (33.4°C). Granite Bay reports a sharp reduction in temperature during September, averaging at a refreshing 58.1°F (14.5°C) at night.Heat index
The heat index for September is evaluated at a tropical 86°F (30°C). Persistent activity under exposure might lead to a feeling of weariness, with subsequent heat cramps.For clarity, heat index numbers account for light winds and areas under shade. Exposure to unobstructed sunshine could lead to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', offers an insight into how hot it feels when we factor in moisture content. The experience of temperature can be subjective, varying based on the individual's activity and heat perception, influenced by factors like wind, attire, and metabolic variations. Direct sun exposure is noteworthy in its ability to escalate the felt temperature, potentially adding 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are particularly relevant to babies and toddlers. Young children typically face greater hazards than adults because they do not sweat as much. Their larger skin surface in comparison to their little bodies and the high heat production from their active nature compounds their vulnerability.
Humidity
In September, the average relative humidity in Granite Bay, California, is 41%.Rainfall
In Granite Bay, in September, it is raining for 2.6 days, with typically 0.24" (6mm) of accumulated precipitation. Throughout the year, in Granite Bay, California, there are 81.2 rainfall days, and 22.64" (575mm) of precipitation is accumulated.Snowfall
In Granite Bay, snow does not fall in January, March through November.Daylight
In September, the average length of the day is 12h and 25min.On the first day of September in Granite Bay, California, sunrise is at 6:34 am and sunset at 7:34 pm. On the last day of the month, sunrise is at 7:00 am and sunset at 6:48 pm PDT.
Sunshine
The average sunshine in September is 11.3h.UV index
The average daily maximum UV index in September in Granite Bay is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: In September, the maximum UV index of 5 suggests this advice:
Act with care - The suggestion to avoid sunburn is emphasized. To guard against the harmful effects of the Sun, minimize exposure during midday. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Granite Bay, CA
- Average high temperature in September: 86.9°F
The warmest month (with the highest average high temperature) is July (93°F).
The month with the lowest average high temperature is December (54°F).
- Average low temperature in September: 58.1°F
The month with the highest average low temperature is July (60.3°F).
The coldest month (with the lowest average low temperature) is December (39.6°F).
Average pressure in September
Granite Bay, CA
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Granite Bay, CA
- Average wind speed in September: 4mph
The windiest month (with the highest average wind speed) is February (5.5mph).
The calmest months (with the lowest average wind speed) are August and September (4mph).
Average humidity in September
Granite Bay, CA
- Average humidity in September: 41%
The month with the highest relative humidity is March (74%).
The month with the lowest relative humidity is July (40%).
Average rainfall in September
Granite Bay, CA
- Average rainfall in September: 0.24"
The wettest month (with the highest rainfall) is March (4.33").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in September
Granite Bay, CA
- Average rainfall days in September: 2.6 days
The month with the highest number of rainy days is March (14.6 days).
The month with the least rainy days is July (1 days).
Average snowfall in September
Granite Bay, CA
- Average snowfall in September: 0"
The months with the highest snowfall are February and December (0.04").
The months with the least snowfall are January, March, April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Granite Bay, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.2 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Granite Bay, 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 30min).
- Average sunshine in September: 11h and 18min
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
Granite Bay, CA
- Average sunshine days in September: 26.6 days
The month with the most sunshine days is July (29.2 days).
The month with the least sunshine days is March (15.7 days).
Average UV index in September
Granite Bay, CA
- Average UV index in September: 5
The months with the highest UV index are June and July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in September
Granite Bay, CA
- Average cloud cover in September: 8
The month with the most cloud cover is March (Cloud cover 38).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in September
Granite Bay, 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).
