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 snowfall in September
- Average snowfall 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
September's advent notes a subtle adjustment in average high-temperature to an agreeable 72.5°F (22.5°C) from August. In stark contrast to the day's heat, the temperature dips to an average of 50.9°F (10.5°C) during September nights.Humidity
September is the least humid month in Rio Dell, with an average relative humidity of 73%.Rainfall
In Rio Dell, during September, the rain falls for 4 days and regularly aggregates up to 0.59" (15mm) of precipitation. Throughout the year, there are 110.9 rainfall days, and 28.27" (718mm) of precipitation is accumulated.Snowfall
In Rio Dell, snow does not fall in January, March through December.Daylight
In Rio Dell, California, the average length of the day in September is 12h and 26min.On the first day of September in Rio Dell, sunrise is at 6:44 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 6:59 pm PDT.
Sunshine
In September, the average sunshine in Rio Dell is 10.2h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for the average person.Note: The UV index of 4 during September translates into the following guidance:
Take heed. Individuals of lighter complexion can be burned in less than half an hour. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Frequently asked questions
What is the usual temperature for Rio Dell in September?
What is the least humid month in Rio Dell?
What is the average humidity in September in Rio Dell?
How many days does it rain in September in Rio Dell?
When it does not snow in Rio Dell?
How many hours of daylight does Rio Dell have in September?
What time are sunrise and sunset in September in Rio Dell?
How many hours of sunshine does Rio Dell have in September?
What is the UV index reading in September in Rio Dell?
Average temperature in September
Rio Dell, CA
- Average high temperature in September: 72.5°F
The warmest month (with the highest average high temperature) is August (74.1°F).
The month with the lowest average high temperature is December (52.9°F).
- Average low temperature in September: 50.9°F
The month with the highest average low temperature is August (51.8°F).
The coldest month (with the lowest average low temperature) is February (39.7°F).
Average pressure in September
Rio Dell, CA
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are August and September (29.96"Hg).
Average wind speed in September
Rio Dell, CA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is June (7.7mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in September
Rio Dell, CA
- Average humidity in September: 73%
The month with the highest relative humidity is March (83%).
The month with the lowest relative humidity is September (73%).
Average rainfall in September
Rio Dell, CA
- Average rainfall in September: 0.59"
The wettest month (with the highest rainfall) is December (4.96").
The driest month (with the least rainfall) is July (0.08").
Average rainfall days in September
Rio Dell, CA
- Average rainfall days in September: 4 days
The month with the highest number of rainy days is March (17.3 days).
The months with the least rainy days are July and August (1.8 days).
Average snowfall in September
Rio Dell, CA
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.59").
The months with the least snowfall are January, March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Rio Dell, CA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.3 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
Rio Dell, CA
- Average daylight in September: 12h and 2min
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 18min).
- Average sunshine in September: 10h and 1min
The months with the most sunshine are July and August (Average sunshine: 11h and 36min).
The month with the least sunshine is December (Average sunshine: 5h and 0min).
Average sunshine days in September
Rio Dell, CA
- Average sunshine days in September: 25.8 days
The month with the most sunshine days is July (28.5 days).
The month with the least sunshine days is March (11.9 days).
Average UV index in September
Rio Dell, CA
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, November and December (UV index 3).
Average cloud cover in September
Rio Dell, CA
- Average cloud cover in September: 19
The month with the most cloud cover is March (Cloud cover 48).
The month with the least cloud cover is August (Cloud cover 16).
Average visibility in September
Rio Dell, CA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, June, September, October, November and December (6mi).
The months with the lowest visibility are May, July and August (5mi).
Rio Dell, California, USA
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