September weather forecastLyons, CO
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Lyons, Colorado, with an average temperature varying between 72.5°F (22.5°C) and 47.3°F (8.5°C).Temperature
September's arrival subtly correlates with a reduction in the average high-temperature, down from a moderately hot 79.5°F (26.4°C) in August to an agreeable 72.5°F (22.5°C). Lyons's September nights represent a significant downturn from the day's heat, with an average temperature of 47.3°F (8.5°C).Humidity
The months with the lowest humidity are June, August and September, with an average relative humidity of 46%.Rainfall
In Lyons, Colorado, during September, the rain falls for 11.9 days and regularly aggregates up to 1.22" (31mm) of precipitation. In Lyons, during the entire year, the rain falls for 134.2 days and collects up to 17.13" (435mm) of precipitation.Snowfall
In Lyons, snow does not fall in June through September.Daylight
In Lyons, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:29 am and sunset at 7:32 pm. On the last day of September, sunrise is at 6:57 am and sunset at 6:44 pm MDT.
Sunshine
In September, the average sunshine is 10.9h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 4 during September translates into the following directions:
Ensure safety - Sun damage prevention is strongly urged. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. Experience reduced UV exposure by about half when donning a wide-brim hat. Mark this! Snow reflection can nearly double the UV radiation intensity from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lyons, CO
- Average high temperature in September: 72.5°F
The warmest month (with the highest average high temperature) is July (80.6°F).
The month with the lowest average high temperature is December (35.4°F).
- Average low temperature in September: 47.3°F
The month with the highest average low temperature is July (54.5°F).
The coldest month (with the lowest average low temperature) is December (17.6°F).
Average pressure in September
Lyons, CO
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The months with the lowest atmospheric pressure are April and June (29.91"Hg).
Average wind speed in September
Lyons, CO
- Average wind speed in September: 5.6mph
The windiest month (with the highest average wind speed) is January (7.3mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in September
Lyons, CO
- Average humidity in September: 46%
The month with the highest relative humidity is February (71%).
The months with the lowest relative humidity are June, August and September (46%).
Average rainfall in September
Lyons, CO
- Average rainfall in September: 1.22"
The wettest month (with the highest rainfall) is May (2.72").
The driest month (with the least rainfall) is January (0.55").
Average rainfall days in September
Lyons, CO
- Average rainfall days in September: 11.9 days
The month with the highest number of rainy days is July (20.4 days).
The month with the least rainy days is November (3.6 days).
Average snowfall in September
Lyons, CO
- Average snowfall in September: 0"
The month with the highest snowfall is April (8.39").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Lyons, CO
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (11 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Lyons, 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 24min).
- Average sunshine in September: 10h and 54min
The months with the most sunshine are June and July (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 6h and 36min).
Average sunshine days in September
Lyons, CO
- Average sunshine days in September: 14.2 days
The month with the most sunshine days is November (21.5 days).
The month with the least sunshine days is July (7.3 days).
Average UV index in September
Lyons, CO
- 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, October, November and December (UV index 2).
Average cloud cover in September
Lyons, CO
- Average cloud cover in September: 17
The months with the most cloud cover are April and May (Cloud cover 28).
The months with the least cloud cover are June and September (Cloud cover 17).
Average visibility in September
Lyons, 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).
