September weather forecastFrederick, CO
September
Weather in September
The first month of the autumn, September, is still a warm month in Frederick, Colorado, with temperature in the range of an average high of 80.1°F (26.7°C) and an average low of 53.4°F (11.9°C).Temperature
September witnesses a gentle descent in average high-temperature, descending from August's tropical 88.2°F (31.2°C) to a moderately hot 80.1°F (26.7°C). Frederick, in September, experiences a marked contrast from daytime zeniths to a steady average low-temperature of 53.4°F (11.9°C).Humidity
The average relative humidity in September in Frederick, Colorado, is 41%.Rainfall
In Frederick, in September, during 7.5 rainfall days, 0.55" (14mm) of precipitation is typically accumulated. Throughout the year, in Frederick, there are 87 rainfall days, and 9.88" (251mm) of precipitation is accumulated.Snowfall
June through September are months without snowfall in Frederick.Daylight
In Frederick, the average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:30 pm. On the last day of September, in Frederick, sunrise is at 6:55 am and sunset at 6:43 pm MDT.
Sunshine
In September, the average sunshine in Frederick, Colorado, is 10.9h.UV index
In September, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: In September, an average UV index of 4 transforms into the following instructions:
Heed the precautions - Protecting the skin and eyes from damage is compulsory. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Stay sun-safe with clothing that is both closely woven and worn loosely. Be alert! Nearly double the UV rays from the Sun can be reflected by snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Frederick, CO
- Average high temperature in September: 80.1°F
The warmest month (with the highest average high temperature) is July (89.2°F).
The month with the lowest average high temperature is December (40.8°F).
- Average low temperature in September: 53.4°F
The month with the highest average low temperature is July (61.5°F).
The coldest month (with the lowest average low temperature) is December (21°F).
Average pressure in September
Frederick, CO
- Average pressure in September: 30"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in September
Frederick, CO
- Average wind speed in September: 5.9mph
The windiest month (with the highest average wind speed) is April (7mph).
The calmest month (with the lowest average wind speed) is December (5.7mph).
Average humidity in September
Frederick, CO
- Average humidity in September: 41%
The month with the highest relative humidity is February (64%).
The month with the lowest relative humidity is August (40%).
Average rainfall in September
Frederick, CO
- Average rainfall in September: 0.55"
The wettest month (with the highest rainfall) is May (1.69").
The driest months (with the least rainfall) are January and December (0.35").
Average rainfall days in September
Frederick, CO
- Average rainfall days in September: 7.5 days
The months with the highest number of rainy days are May and July (12.3 days).
The months with the least rainy days are January and December (3 days).
Average snowfall in September
Frederick, CO
- Average snowfall in September: 0"
The month with the highest snowfall is April (4.45").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Frederick, CO
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (7.8 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Frederick, 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 48min).
The month with the least sunshine is February (Average sunshine: 6h and 42min).
Average sunshine days in September
Frederick, CO
- Average sunshine days in September: 18.5 days
The month with the most sunshine days is December (24.5 days).
The month with the least sunshine days is July (12.8 days).
Average UV index in September
Frederick, 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
Frederick, CO
- Average cloud cover in September: 15
The month with the most cloud cover is April (Cloud cover 27).
The month with the least cloud cover is September (Cloud cover 15).
Average visibility in September
Frederick, 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).
