September weather forecastFort Lyon, CO
September
Weather in September
The first month of the autumn, September, is still a warm month in Fort Lyon, Colorado, with an average temperature varying between 61.9°F (16.6°C) and 83.5°F (28.6°C).Temperature
In the transition to September, Fort Lyon observes a minor drop in the average high-temperature, shifting from a tropical 90.1°F (32.3°C) in August to a warm 83.5°F (28.6°C). September nights bring a pronounced temperature shift, with averages hovering around a comfortable 61.9°F (16.6°C).Heat index
In September, the average heat index is computed to be 82.4°F (28°C). Prolonged activity during exposure might result in a state of fatigue and cause heat cramps.The heat index's values are generally associated with conditions in shade and light breezes. With exposure to direct sunshine, the heat index could climb by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', is an amalgamation of air temperature and humidity to express the equivalent perceived temperature. The impact of temperature is individual, as people's perception of weather may change based on their body mass, height, and physical activity. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Young ones often ignore the need to take a break and drink fluids. Thirst is a late-stage symptom of dehydration - hence, maintaining hydration, particularly during extended physical activities, is crucial.
Humidity
In Fort Lyon, the average relative humidity in September is 43%.Rainfall
In Fort Lyon, in September, during 7.8 rainfall days, 0.71" (18mm) of precipitation is typically accumulated. In Fort Lyon, during the entire year, the rain falls for 89.9 days and collects up to 10.2" (259mm) of precipitation.Snowfall
In Fort Lyon, Colorado, snow does not fall in June through September.Daylight
In September, the average length of the day is 12h and 25min.On the first day of the month, sunrise is at 6:22 am and sunset at 7:21 pm. On the last day of September, sunrise is at 6:47 am and sunset at 6:36 pm MDT.
Sunshine
The average sunshine in September is 10.6h.UV index
In Fort Lyon, the average daily maximum UV index in September is 5. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum UV index of 5 during September translates into these guidelines:
Be vigilant - A duty to shield skin and eyes from injury exists. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Fort Lyon, CO
- Average high temperature in September: 83.5°F
The warmest month (with the highest average high temperature) is July (92.8°F).
The month with the lowest average high temperature is December (43.7°F).
- Average low temperature in September: 61.9°F
The month with the highest average low temperature is July (70.9°F).
The coldest month (with the lowest average low temperature) is December (26.6°F).
Average pressure in September
Fort Lyon, CO
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.82"Hg).
Average wind speed in September
Fort Lyon, CO
- Average wind speed in September: 10.3mph
The windiest month (with the highest average wind speed) is April (11.7mph).
The calmest month (with the lowest average wind speed) is January (8.2mph).
Average humidity in September
Fort Lyon, CO
- Average humidity in September: 43%
The month with the highest relative humidity is January (58%).
The month with the lowest relative humidity is June (38%).
Average rainfall in September
Fort Lyon, CO
- Average rainfall in September: 0.71"
The wettest month (with the highest rainfall) is July (1.81").
The driest months (with the least rainfall) are January, November and December (0.35").
Average rainfall days in September
Fort Lyon, CO
- Average rainfall days in September: 7.8 days
The month with the highest number of rainy days is July (13.8 days).
The month with the least rainy days is January (3.3 days).
Average snowfall in September
Fort Lyon, CO
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.17").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Fort Lyon, CO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (5.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Fort Lyon, CO
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in September: 10h and 36min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is February (Average sunshine: 6h and 42min).
Average sunshine days in September
Fort Lyon, CO
- Average sunshine days in September: 19.9 days
The month with the most sunshine days is November (24.5 days).
The month with the least sunshine days is July (13.2 days).
Average UV index in September
Fort Lyon, CO
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 7).
The months with the lowest UV index are January, November and December (UV index 2).
Average cloud cover in September
Fort Lyon, CO
- Average cloud cover in September: 14
The months with the most cloud cover are February and April (Cloud cover 25).
The months with the least cloud cover are June and September (Cloud cover 14).
Average visibility in September
Fort Lyon, 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).
