September weather forecastLouisville, CO
September
Weather in September
September, the first month of the autumn in Louisville, is still a warm month, with an average temperature varying between 76.6°F (24.8°C) and 50.7°F (10.4°C).Temperature
As August makes way for September, Louisville's average high-temperature eases from 84.2°F (29°C) to a still warm 76.6°F (24.8°C). September in Louisville, Colorado, marked by an average low-temperature of 50.7°F (10.4°C), indicates a large temperature drop from the daytime peak.Humidity
In September, the average relative humidity in Louisville is 43%.Rainfall
In September, in Louisville, the rain falls for 7.7 days. Throughout September, 0.35" (9mm) of precipitation is accumulated. In Louisville, during the entire year, the rain falls for 96.7 days and collects up to 5.63" (143mm) of precipitation.Snowfall
June through September are months without snowfall in Louisville.Daylight
In September, the average length of the day in Louisville, Colorado, is 12h and 26min.On the first day of September, sunrise is at 6:29 am and sunset at 7:31 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 6:43 pm MDT.
Sunshine
In September, the average sunshine is 11.1h.UV index
The average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: In September, the average maximum UV index of 4 translates into the following recommendations:
Exercise prevention - Precautions against solar damage are endorsed. Considering the harmful UV rays from the Sun during midday, it's essential to reduce exposure. A wide-brimmed hat provides unparalleled sun protection for sensitive areas like the eyes, ears, and neck.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Louisville, CO
- Average high temperature in September: 76.6°F
The warmest month (with the highest average high temperature) is July (85.5°F).
The month with the lowest average high temperature is December (39.4°F).
- Average low temperature in September: 50.7°F
The month with the highest average low temperature is July (59°F).
The coldest months (with the lowest average low temperature) are February and December (20.7°F).
Average pressure in September
Louisville, CO
- Average pressure in September: 30.01"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are April and June (29.91"Hg).
Average wind speed in September
Louisville, CO
- Average wind speed in September: 5.6mph
The windiest months (with the highest average wind speed) are March and April (6.5mph).
The calmest month (with the lowest average wind speed) is September (5.6mph).
Average humidity in September
Louisville, CO
- Average humidity in September: 43%
The month with the highest relative humidity is February (67%).
The month with the lowest relative humidity is August (41%).
Average rainfall in September
Louisville, CO
- Average rainfall in September: 0.35"
The wettest months (with the highest rainfall) are May and July (0.87").
The driest month (with the least rainfall) is January (0.16").
Average rainfall days in September
Louisville, CO
- Average rainfall days in September: 7.7 days
The month with the highest number of rainy days is May (14.4 days).
The month with the least rainy days is November (3.5 days).
Average snowfall in September
Louisville, CO
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.68").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Louisville, CO
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (8.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Louisville, 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: 11h and 6min
The months with the most sunshine are June, July and August (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 6h and 42min).
Average sunshine days in September
Louisville, CO
- Average sunshine days in September: 18 days
The month with the most sunshine days is November (23.7 days).
The month with the least sunshine days is July (10 days).
Average UV index in September
Louisville, CO
- Average UV index in September: 4
The months with the highest UV index are 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
Louisville, CO
- Average cloud cover in September: 15
The months with the most cloud cover are April and May (Cloud cover 26).
The month with the least cloud cover is September (Cloud cover 15).
Average visibility in September
Louisville, 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).
