September weather forecastMill Creek, CA
September
Weather in September
The first month of the autumn, September, is still a warm month in Mill Creek, California, with an average temperature varying between 44.6°F (7°C) and 73.4°F (23°C).Temperature
The arrival of September is marked by a minor reduction in average high-temperature, sliding from a warm 80.2°F (26.8°C) in August to a still moderately hot 73.4°F (23°C). The average low-temperature of 44.6°F (7°C) in September represents a significant drop from the daily high.Humidity
In Mill Creek, the average relative humidity in September is 47%.Rainfall
In Mill Creek, in September, it is raining for 5.5 days, with typically 0.67" (17mm) of accumulated precipitation. Throughout the year, there are 98.1 rainfall days, and 32.99" (838mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.47" (12mm) of snow. In Mill Creek, during the entire year, snow falls for 66 days and aggregates up to 127.72" (3244mm) of snow.Daylight
The average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:34 am and sunset at 7:37 pm. On the last day of September, sunrise is at 7:02 am and sunset at 6:49 pm PDT.
Sunshine
In Mill Creek, the average sunshine in September is 11.1h.UV index
In September, the average daily maximum UV index is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: A daily high UV index of 4 in September leads to these guidelines:
Preventative actions are necessary - Suggestions to safeguard against sun damage are in order. Avoiding the Sun during its peak radiation time around midday is a healthy practice. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes. Be alert! Nearly double the UV rays from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Mill Creek, CA
- Average high temperature in September: 73.4°F
The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is December (38.3°F).
- Average low temperature in September: 44.6°F
The month with the highest average low temperature is July (49.5°F).
The coldest month (with the lowest average low temperature) is December (24.1°F).
Average pressure in September
Mill Creek, CA
- Average pressure in September: 29.93"Hg
The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Mill Creek, CA
- Average wind speed in September: 5.2mph
The windiest month (with the highest average wind speed) is March (6.7mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in September
Mill Creek, CA
- Average humidity in September: 47%
The month with the highest relative humidity is March (83%).
The month with the lowest relative humidity is July (42%).
Average rainfall in September
Mill Creek, CA
- Average rainfall in September: 0.67"
The wettest month (with the highest rainfall) is March (5.59").
The driest month (with the least rainfall) is July (0.39").
Average rainfall days in September
Mill Creek, CA
- Average rainfall days in September: 5.5 days
The month with the highest number of rainy days is May (13.4 days).
The month with the least rainy days is August (4 days).
Average snowfall in September
Mill Creek, CA
- Average snowfall in September: 0.47"
The month with the highest snowfall is March (27.05").
The months with the least snowfall are July and August (0").
Average snowfall days in September
Mill Creek, CA
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is March (14 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in September /
Average sunshine in September
Mill Creek, CA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in September: 11h and 6min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 5h and 6min).
Average sunshine days in September
Mill Creek, CA
- Average sunshine days in September: 23.1 days
The month with the most sunshine days is August (25 days).
The month with the least sunshine days is March (10.9 days).
Average UV index in September
Mill Creek, CA
- Average UV index in September: 4
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are February and November (UV index 1).
Average cloud cover in September
Mill Creek, CA
- Average cloud cover in September: 12
The month with the most cloud cover is March (Cloud cover 50).
The months with the least cloud cover are July and August (Cloud cover 7).
Average visibility in September
Mill Creek, CA
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).
