September weather forecastGreeley, CO
September
Weather in September
September indicates the onset of autumn in Greeley, Colorado. Warm summer days start to be replaced by cooler autumnal temperatures. The high temperatures reduce more, leading to a crisper climate. Despite the initial dip in temperature, the city continues to receive a good amount of sunshine. The arrival of fall colors starts becoming evident across the landscape.Temperature
September indicates a minor shift in the average high-temperature, from August's hot 87.8°F (31°C) to a warm 79.7°F (26.5°C). Greeley's daily high temperature significantly diverges from the consistently recorded temperature low averaging a fresh 53.8°F (12.1°C) in September.Humidity
August and September, with an average relative humidity of 44%, are the least humid months.Rainfall
In Greeley, in September, during 6.7 rainfall days, 0.55" (14mm) of precipitation is typically accumulated. In Greeley, during the entire year, the rain falls for 71.4 days and collects up to 7.6" (193mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:26 am and sunset at 7:30 pm. On the last day of the month, sunrise is at 6:55 am and sunset at 6:42 pm MDT.
Sunshine
In Greeley, the average sunshine in September is 10.8h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for the average person.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Act with care - Obligation to protect against skin and eye damage is highlighted. Stay safe from the Sun's strongest UV rays by limiting exposure during midday. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Greeley, CO
- Average high temperature in September: 79.7°F
The warmest month (with the highest average high temperature) is July (89.1°F).
The month with the lowest average high temperature is December (38.3°F).
- Average low temperature in September: 53.8°F
The month with the highest average low temperature is July (62.1°F).
The coldest month (with the lowest average low temperature) is December (20.1°F).
Average pressure in September
Greeley, CO
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in September
Greeley, CO
- Average wind speed in September: 6.3mph
The windiest month (with the highest average wind speed) is April (8.5mph).
The calmest month (with the lowest average wind speed) is December (6mph).
Average humidity in September
Greeley, CO
- Average humidity in September: 44%
The months with the highest relative humidity are January and December (64%).
The months with the lowest relative humidity are August and September (44%).
Average rainfall in September
Greeley, CO
- Average rainfall in September: 0.55"
The wettest month (with the highest rainfall) is May (1.61").
The driest month (with the least rainfall) is December (0.2").
Average rainfall days in September
Greeley, CO
- Average rainfall days in September: 6.7 days
The month with the highest number of rainy days is July (11.4 days).
The month with the least rainy days is November (1.6 days).
Average snowfall in September
Greeley, CO
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.36").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Greeley, CO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (5.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Greeley, CO
- 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 18min).
- Average sunshine in September: 10h and 48min
The month with the most sunshine is June (Average sunshine: 11h and 54min).
The months with the least sunshine are February and December (Average sunshine: 6h and 36min).
Average sunshine days in September
Greeley, CO
- Average sunshine days in September: 22 days
The month with the most sunshine days is December (25.9 days).
The month with the least sunshine days is July (16.7 days).
Average UV index in September
Greeley, CO
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Greeley, CO
- Average cloud cover in September: 17
The month with the most cloud cover is February (Cloud cover 29).
The month with the least cloud cover is June (Cloud cover 16).
Average visibility in September
Greeley, CO
- 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).
