September weather forecastJamestown, CO
September
Weather in September
September, the first month of the autumn in Jamestown, is also an agreeable month, with an average temperature varying between 47.8°F (8.8°C) and 72.3°F (22.4°C).Temperature
A mild shift in the average high-temperature occurs in September, reducing from a warm 79.5°F (26.4°C) in August to a pleasant 72.3°F (22.4°C). Jamestown encounters a substantial decline from its daily high to a low-temperature of 47.8°F (8.8°C) during September nights.Humidity
The months with the lowest humidity are June, August and September, with an average relative humidity of 45%.Rainfall
In Jamestown, during September, the rain falls for 9.9 days and regularly aggregates up to 1.02" (26mm) of precipitation. In Jamestown, during the entire year, the rain falls for 117.3 days and collects up to 14.17" (360mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in September in Jamestown is 12h and 26min.On the first day of September, sunrise is at 6:30 am and sunset at 7:32 pm. On the last day of the month, 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 reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: In September, a daily UV index of 4 turns into the following recommendations:
Take necessary precautions - Defending against sun damage is advocated. Exposing oneself to the midday Sun can be harmful due to the strong UV radiation; limit your time outside. Employ a hat with a wide brim for robust protection, cutting UV exposure by half. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Jamestown, CO
- Average high temperature in September: 72.3°F
The warmest month (with the highest average high temperature) is July (80.4°F).
The month with the lowest average high temperature is December (35.2°F).
- Average low temperature in September: 47.8°F
The month with the highest average low temperature is July (55.2°F).
The coldest month (with the lowest average low temperature) is February (18°F).
Average pressure in September
Jamestown, 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, May and June (29.92"Hg).
Average wind speed in September
Jamestown, CO
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is January (7.3mph).
The calmest months (with the lowest average wind speed) are May, July, August and September (5.7mph).
Average humidity in September
Jamestown, CO
- Average humidity in September: 45%
The month with the highest relative humidity is February (70%).
The months with the lowest relative humidity are June, August and September (45%).
Average rainfall in September
Jamestown, CO
- Average rainfall in September: 1.02"
The wettest month (with the highest rainfall) is May (2.48").
The driest month (with the least rainfall) is January (0.39").
Average rainfall days in September
Jamestown, CO
- Average rainfall days in September: 9.9 days
The month with the highest number of rainy days is July (17.8 days).
The month with the least rainy days is November (3.3 days).
Average snowfall in September
Jamestown, CO
- Average snowfall in September: 0"
The month with the highest snowfall is April (7.76").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Jamestown, CO
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (10.3 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Jamestown, 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
Jamestown, CO
- Average sunshine days in September: 17.6 days
The month with the most sunshine days is January (22.2 days).
The month with the least sunshine days is July (9.9 days).
Average UV index in September
Jamestown, 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, November and December (UV index 2).
Average cloud cover in September
Jamestown, CO
- Average cloud cover in September: 16
The months with the most cloud cover are April and May (Cloud cover 28).
The month with the least cloud cover is September (Cloud cover 16).
Average visibility in September
Jamestown, 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).
