September weather forecastWestminster, CO
September
Weather in September
September, the first month of the autumn in Westminster, is also a moderately hot month, with an average temperature varying between 52.7°F (11.5°C) and 78.6°F (25.9°C).Temperature
A subtle change in temperatures is noted as August gives way to September, with average highs reducing from a hot 86.2°F (30.1°C) to a warm 78.6°F (25.9°C). The nighttime temperature during September exhibits a clear drop from daytime highs, settling at a fresh 52.7°F (11.5°C).Humidity
In Westminster, the average relative humidity in September is 41%.Rainfall
In Westminster, in September, it is raining for 7.9 days, with typically 0.55" (14mm) of accumulated precipitation. In Westminster, Colorado, during the entire year, the rain falls for 101.9 days and collects up to 10.91" (277mm) of precipitation.Snowfall
In Westminster, snow does not fall in June through September.Daylight
The average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:28 am and sunset at 7:30 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 11h.UV index
In Westminster, the average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: In September, a regular UV index of 5 translates into these guidelines:
Guard yourself - Avoiding sunburn is suggested. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses. Be alert to the fact! The reflection from snow can nearly double the UV radiation of the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Westminster, CO
- Average high temperature in September: 78.6°F
The warmest month (with the highest average high temperature) is July (87.4°F).
The month with the lowest average high temperature is December (41.2°F).
- Average low temperature in September: 52.7°F
The month with the highest average low temperature is July (60.8°F).
The coldest month (with the lowest average low temperature) is December (21.2°F).
Average pressure in September
Westminster, 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
Westminster, CO
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is April (6.7mph).
The calmest months (with the lowest average wind speed) are August, September and December (5.8mph).
Average humidity in September
Westminster, CO
- Average humidity in September: 41%
The month with the highest relative humidity is February (65%).
The months with the lowest relative humidity are June and August (40%).
Average rainfall in September
Westminster, CO
- Average rainfall in September: 0.55"
The wettest month (with the highest rainfall) is May (2.05").
The driest months (with the least rainfall) are January and December (0.35").
Average rainfall days in September
Westminster, CO
- Average rainfall days in September: 7.9 days
The month with the highest number of rainy days is May (15.6 days).
The month with the least rainy days is January (3.3 days).
Average snowfall in September
Westminster, CO
- Average snowfall in September: 0"
The month with the highest snowfall is April (5.55").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Westminster, CO
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (9.4 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Westminster, 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 0min
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
Westminster, CO
- Average sunshine days in September: 17.5 days
The month with the most sunshine days is December (23.9 days).
The month with the least sunshine days is July (8.8 days).
Average UV index in September
Westminster, CO
- Average UV index in September: 5
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
Westminster, CO
- Average cloud cover in September: 15
The month with the most cloud cover is April (Cloud cover 26).
The month with the least cloud cover is September (Cloud cover 15).
Average visibility in September
Westminster, 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).
