September weather forecastPrescott, AZ

September
Weather in September
September in Prescott marks the transition from summer to fall. Temperatures find their place between 59°F (15°C) and 79.7°F (26.5°C), notably cooler than the peak summer months. The shift from summer culminates in decreased intensity of sunlight being received daily. The UV index starts falling, creating a much-needed respite from the intense summer rays. A drop in rainfall assists the transition from sticky summer to the crisp fall season.Temperature
The onset of September in Prescott aligns with a soft reduction in the average high-temperature, gently falling from a moderately hot 85.1°F (29.5°C) in August to a still warm 79.7°F (26.5°C). Prescott experiences a consistent average temperature of 59°F (15°C) throughout the nights in September.Humidity
In September, the average relative humidity is 42%.Rainfall
In Prescott, during September, the rain falls for 9.8 days and regularly aggregates up to 1.69" (43mm) of precipitation. In Prescott, during the entire year, the rain falls for 76.9 days and collects up to 16.46" (418mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
In September, the average length of the day is 12h and 23min.On the first day of the month, sunrise is at 6:03 am and sunset at 6:55 pm. On the last day of September, sunrise is at 6:24 am and sunset at 6:14 pm MST.
Sunshine
In Prescott, the average sunshine in September is 9.8h.UV index
The average daily maximum UV index in September in Prescott is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV rays for the average person.Note: A daily high UV index of 5 in September leads to these guidelines:
Take precautions - Protection against sunburn is recommended. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Prescott, AZ
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is July (87.3°F).
The month with the lowest average high temperature is December (49.1°F).
- Average low temperature in September: 59°F
The month with the highest average low temperature is July (65.1°F).
The coldest month (with the lowest average low temperature) is December (30.7°F).
Average pressure in September
Prescott, AZ
- Average pressure in September: 29.9"Hg
The month with the highest atmospheric pressure is January (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in September
Prescott, AZ
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is April (8.3mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in September
Prescott, AZ
- Average humidity in September: 42%
The month with the highest relative humidity is December (58%).
The month with the lowest relative humidity is June (23%).
Average rainfall in September
Prescott, AZ
- Average rainfall in September: 1.69"
The wettest month (with the highest rainfall) is July (4.33").
The driest month (with the least rainfall) is June (0.24").
Average rainfall days in September
Prescott, AZ
- Average rainfall days in September: 9.8 days
The months with the highest number of rainy days are July and August (15.5 days).
The month with the least rainy days is June (2.3 days).
Average snowfall in September
Prescott, AZ
- Average snowfall in September: 0"
The month with the highest snowfall is December (4.13").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Prescott, AZ
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is December (3.5 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Prescott, AZ
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in September: 9h and 48min
The month with the most sunshine is June (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in September
Prescott, AZ
- Average sunshine days in September: 18.5 days
The month with the most sunshine days is May (26.8 days).
The month with the least sunshine days is August (12.8 days).
Average UV index in September
Prescott, AZ
- Average UV index in September: 5
The month with the highest UV index is June (UV index 7).
The month with the lowest UV index is December (UV index 2).
Average cloud cover in September
Prescott, AZ
- Average cloud cover in September: 10
The month with the most cloud cover is December (Cloud cover 24).
The month with the least cloud cover is June (Cloud cover 7).
Average visibility in September
Prescott, 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).





