September weather forecastMills, WY
September
Weather in September
September commences the transitionary period of fall, gradually drawing the curtain on Mills' enduring summer. Yet, the city experiences warm afternoons with a high of 72.7°F (22.6°C) and a chance occurrence of a light snowfall of 0.12" (3mm). This month features the harmonious blend of late-summer warmth and the nascent coolth of the approaching autumn. Distinct changes begin to appear in Mills' flora as they prepare for the cooling season. September captures this beautiful alternation on the cusp of two seasons, presenting a picture of a harmonious contradiction.Temperature
Mills, Wyoming, in September undergoes a slight reduction in the average high-temperature, shifting from August's warm 81.3°F (27.4°C) to an agreeable 72.7°F (22.6°C). Mills's average nighttime temperatures present a clear contrast to its daytime highs, measured at a cool 50.9°F (10.5°C) in September.Humidity
In September, the average relative humidity is 40%.Rainfall
The months with the least rainfall in Mills are January, August and September Rain falls for 7.6 days and accumulates 0.43" (11mm) of rain.Snowfall
Months with snowfall are January through May, September through December. September is the first month it typically snows. Throughout September, in the average 0.2 snowfall days, it receives 0.12" (3mm) of snow. In Mills, Wyoming, during the entire year, snow falls for 61.5 days and aggregates up to 32.13" (816mm) of snow.Daylight
In Mills, Wyoming, the average length of the day in September is 12h and 29min.On the first day of September, sunrise is at 6:31 am and sunset at 7:39 pm. On the last day of the month, sunrise is at 7:02 am and sunset at 6:47 pm MDT.
Sunshine
In September, the average sunshine is 11.1h.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 unprotected exposure to Sun's UV rays for ordinary individuals.Note: The UV index of 4 in September translates into these instructions:
Adopt protective measures - Suggestions to resist sunburn are offered. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly. Heads up! The UV radiation from the Sun can almost be doubled by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Mills, WY
- Average high temperature in September: 72.7°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is December (28.4°F).
- Average low temperature in September: 50.9°F
The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is December (15.1°F).
Average pressure in September
Mills, WY
- Average pressure in September: 29.94"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.85"Hg).
Average wind speed in September
Mills, WY
- Average wind speed in September: 9.4mph
The windiest month (with the highest average wind speed) is January (12.1mph).
The calmest months (with the lowest average wind speed) are July and August (8.5mph).
Average humidity in September
Mills, WY
- Average humidity in September: 40%
The month with the highest relative humidity is January (79%).
The month with the lowest relative humidity is August (37%).
Average rainfall in September
Mills, WY
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is May (1.77").
The driest months (with the least rainfall) are January, August and September (0.43").
Average rainfall days in September
Mills, WY
- Average rainfall days in September: 7.6 days
The month with the highest number of rainy days is May (14.1 days).
The month with the least rainy days is January (3.6 days).
Average snowfall in September
Mills, WY
- Average snowfall in September: 0.12"
The month with the highest snowfall is November (5.47").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Mills, WY
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is February (11.2 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Mills, WY
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 11h and 6min
The months with the most sunshine are July and August (Average sunshine: 11h and 54min).
The month with the least sunshine is February (Average sunshine: 6h and 6min).
Average sunshine days in September
Mills, WY
- Average sunshine days in September: 19.2 days
The month with the most sunshine days is December (20.5 days).
The month with the least sunshine days is May (11.9 days).
Average UV index in September
Mills, WY
- 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, March, April, October, November and December (UV index 2).
Average cloud cover in September
Mills, WY
- Average cloud cover in September: 14
The month with the most cloud cover is February (Cloud cover 36).
The month with the least cloud cover is August (Cloud cover 13).
Average visibility in September
Mills, WY
- 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).
