September weather forecastLafayette, CO
September
Weather in September
Signifying the commencement of Fall, September in Lafayette, Colorado sheds the high summer temperatures, making way for milder weather conditions. The city begins to portray a scenic amalgamation of warmer and cooler temperatures. As September transitions into October, the temperatures continue their downward trend. An increase in rainfall accompanies the dipped temperatures, further reverting the landscapes back to their lush, vibrant selves. This month marks a turning point in Lafayette's climatic calendar, heralding the approaching winter.Temperature
The commencement of September in Lafayette indicates a gentle shift in the average high-temperature, receding from August's 84.2°F (29°C) to a still warm 76.6°F (24.8°C). September nights experience a distinct temperature drop from the daily highs, with an average low-temperature of 50.7°F (10.4°C).Humidity
In Lafayette, the average relative humidity in September is 43%.Rainfall
In Lafayette, Colorado, in September, during 7.7 rainfall days, 0.35" (9mm) of precipitation is typically accumulated. Throughout the year, in Lafayette, Colorado, there are 96.7 rainfall days, and 5.63" (143mm) of precipitation is accumulated.Snowfall
In Lafayette, snow does not fall in June through September.Daylight
The average length of the day in September in Lafayette is 12h and 26min.On the first day of September in Lafayette, Colorado, sunrise is at 6:28 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 Lafayette, the average sunshine in September is 11.1h.UV index
The average daily maximum UV index in September in Lafayette is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for the ordinary person.Note: An average UV index of 4 in September transforms into this advice:
Ensure safety - Recommendations to avert sunburn are presented. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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
Lafayette, 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).
