September weather forecastRiviera, AZ
September
Weather in September
September, the first month of the autumn in Riviera, is also a hot month, with temperature in the range of an average high of 92.8°F (33.8°C) and an average low of 75°F (23.9°C).Temperature
The shift from August to September includes a small decrease in the average high-temperature, from a fiery hot 100°F (37.8°C) to a hot 92.8°F (33.8°C). September's nights in Riviera observe an average temperature of 75°F (23.9°C).Humidity
In September, the average relative humidity is 24%.Rainfall
In Riviera, during September, the rain falls for 3.5 days and regularly aggregates up to 0.28" (7mm) of precipitation. In Riviera, during the entire year, the rain falls for 44 days and collects up to 4.21" (107mm) of precipitation.Snowfall
In Riviera, snow does not fall in January through November.Daylight
In Riviera, the average length of the day in September is 12h and 23min.On the first day of the month, sunrise is at 6:11 am and sunset at 7:04 pm. On the last day of September, in Riviera, Arizona, sunrise is at 6:33 am and sunset at 6:23 pm MST.
Sunshine
The average sunshine in September is 9.9h.UV index
The average daily maximum UV index in September is 7. A UV Index reading of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for ordinary individuals.Note: In September, the maximum UV index of 7 suggests these recommendations:
Inhibit overexposure. Warding off sun damage is of utmost importance. Minimize exposure to direct sunlight and seek shade from 10 a.m. to 4 p.m., when UV radiation is most intense, but remember that shade structures may not offer complete protection. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Riviera, AZ
- Average high temperature in September: 92.8°F
The warmest month (with the highest average high temperature) is July (100.8°F).
The month with the lowest average high temperature is December (56.3°F).
- Average low temperature in September: 75°F
The month with the highest average low temperature is August (81.5°F).
The coldest month (with the lowest average low temperature) is December (43.5°F).
Average pressure in September
Riviera, AZ
- Average pressure in September: 29.83"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.76"Hg).
Average wind speed in September
Riviera, AZ
- Average wind speed in September: 7.6mph
The windiest month (with the highest average wind speed) is April (10.1mph).
The calmest month (with the lowest average wind speed) is September (7.6mph).
Average humidity in September
Riviera, AZ
- Average humidity in September: 24%
The month with the highest relative humidity is January (42%).
The month with the lowest relative humidity is June (14%).
Average rainfall in September
Riviera, AZ
- Average rainfall in September: 0.28"
The wettest month (with the highest rainfall) is December (0.67").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in September
Riviera, AZ
- Average rainfall days in September: 3.5 days
The month with the highest number of rainy days is July (5.9 days).
The month with the least rainy days is June (1.1 days).
Average snowfall days in September
Riviera, AZ
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Riviera, AZ
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in September: 9h and 54min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 7h and 0min).
Average sunshine days in September
Riviera, AZ
- Average sunshine days in September: 24.6 days
The month with the most sunshine days is June (28.3 days).
The month with the least sunshine days is July (20.3 days).
Average UV index in September
Riviera, AZ
- Average UV index in September: 7
The months with the highest UV index are June, July and August (UV index 8).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
Riviera, AZ
- Average cloud cover in September: 6
The month with the most cloud cover is December (Cloud cover 19).
The month with the least cloud cover is June (Cloud cover 5).
Average visibility in September
Riviera, AZ
- 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).





