September weather forecastHanna, WY
September
Weather in September
September, the first month of the autumn in Hanna, is still a pleasant month, with temperature in the range of an average high of 70.9°F (21.6°C) and an average low of 50.2°F (10.1°C).Temperature
The arrival of September corresponds with a minor reduction in the average high-temperature, down from August's moderately hot 79.7°F (26.5°C) to a pleasant 70.9°F (21.6°C). Nighttime temperature experiences an average drop to a fresh 50.2°F (10.1°C) in September.Humidity
In September, the average relative humidity is 38%.Rainfall
In September, the rain falls for 6.2 days. Throughout September, 0.39" (10mm) of precipitation is accumulated. Throughout the year, there are 80.5 rainfall days, and 8.39" (213mm) of precipitation is accumulated.Snowfall
January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.1 snowfall days, it receives 0.04" (1mm) of snow. Throughout the year, there are 70.3 snowfall days, and 29.57" (751mm) of snow is accumulated.Daylight
In September, the average length of the day is 12h and 28min.On the first day of September, sunrise is at 6:32 am and sunset at 7:39 pm. On the last day of the month, sunrise is at 7:02 am and sunset at 6:48 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 reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The daily high UV index of 4 during September translates into the following recommendations:
Take necessary precautions - Suggestions to elude sunburn are provided. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance. Warning! The reflection from snow can nearly magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Hanna, WY
- Average high temperature in September: 70.9°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is December (26.4°F).
- Average low temperature in September: 50.2°F
The month with the highest average low temperature is July (58.3°F).
The coldest month (with the lowest average low temperature) is December (13.1°F).
Average pressure in September
Hanna, WY
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.21"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in September
Hanna, WY
- Average wind speed in September: 10.5mph
The windiest month (with the highest average wind speed) is November (12.4mph).
The calmest months (with the lowest average wind speed) are July and August (9.3mph).
Average humidity in September
Hanna, WY
- Average humidity in September: 38%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is August (34%).
Average rainfall in September
Hanna, WY
- Average rainfall in September: 0.39"
The wettest month (with the highest rainfall) is April (1.34").
The driest month (with the least rainfall) is August (0.24").
Average rainfall days in September
Hanna, WY
- Average rainfall days in September: 6.2 days
The month with the highest number of rainy days is May (12.3 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in September
Hanna, WY
- Average snowfall in September: 0.04"
The month with the highest snowfall is March (5.47").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Hanna, WY
- Average snowfall days in September: 0.1 days
The month with the highest number of snowfall days is February (12.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Hanna, WY
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 11h and 6min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The months with the least sunshine are February and December (Average sunshine: 5h and 54min).
Average sunshine days in September
Hanna, WY
- Average sunshine days in September: 22.4 days
The month with the most sunshine days is August (23.6 days).
The month with the least sunshine days is April (12.6 days).
Average UV index in September
Hanna, WY
- Average UV index in September: 4
The month with the highest UV index is July (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
Hanna, WY
- Average cloud cover in September: 14
The month with the most cloud cover is February (Cloud cover 43).
The month with the least cloud cover is August (Cloud cover 13).
Average visibility in September
Hanna, WY
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is December (5mi).
