September weather forecastShell, WY
September
Weather in September
The first month of the autumn, September, is still a mild month in Shell, Wyoming, with temperature in the range of an average high of 59.7°F (15.4°C) and an average low of 40.5°F (4.7°C).Temperature
September signifies a minor drop in average high-temperature, transitioning from 67.5°F (19.7°C) in August to a still refreshing 59.7°F (15.4°C). An average low-temperature of 40.5°F (4.7°C) is recorded during the nights in September.Humidity
In September, the average relative humidity is 54%.Rainfall
In Shell, in September, during 9.7 rainfall days, 1.3" (33mm) of precipitation is typically accumulated. Throughout the year, there are 94.3 rainfall days, and 19.13" (486mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through June, August through December. In Shell, in September, snow falls for 3.1 days, with typically accumulated 3.43" (87mm) of snow. In Shell, during the entire year, snow falls for 113.3 days and aggregates up to 89.02" (2261mm) of snow.Daylight
In Shell, the average length of the day in September is 12h and 30min.On the first day of September, sunrise is at 6:34 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:08 am and sunset at 6:52 pm MDT.
Sunshine
In September, the average sunshine is 10.6h.UV index
The average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: The maximum daily UV index of 3 in September interprets into the following recommendations:
Exercise prevention - Warding off sunburn is urged. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Take to heart! Snow reflection can almost 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
Shell, WY
- Average high temperature in September: 59.7°F
The warmest month (with the highest average high temperature) is July (69.4°F).
The month with the lowest average high temperature is December (20.8°F).
- Average low temperature in September: 40.5°F
The month with the highest average low temperature is July (48.7°F).
The coldest month (with the lowest average low temperature) is December (2.3°F).
Average pressure in September
Shell, WY
- Average pressure in September: 29.94"Hg
The months with the highest atmospheric pressure are January and December (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in September
Shell, WY
- Average wind speed in September: 5.4mph
The windiest month (with the highest average wind speed) is June (6.3mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in September
Shell, WY
- Average humidity in September: 54%
The month with the highest relative humidity is February (85%).
The month with the lowest relative humidity is August (51%).
Average rainfall in September
Shell, WY
- Average rainfall in September: 1.3"
The wettest month (with the highest rainfall) is May (3.62").
The driest month (with the least rainfall) is December (0.75").
Average rainfall days in September
Shell, WY
- Average rainfall days in September: 9.7 days
The month with the highest number of rainy days is July (16.5 days).
The month with the least rainy days is November (2.3 days).
Average snowfall in September
Shell, WY
- Average snowfall in September: 3.43"
The month with the highest snowfall is May (19.33").
The month with the least snowfall is July (0").
Average snowfall days in September
Shell, WY
- Average snowfall days in September: 3.1 days
The month with the highest number of snowfall days is January (15.8 days).
The month with the least snowfall days is July (0 days).
Average daylight in September /
Average sunshine in September
Shell, WY
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in September: 10h and 36min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Shell, WY
- Average sunshine days in September: 16.3 days
The month with the most sunshine days is November (19.7 days).
The month with the least sunshine days is June (8.6 days).
Average UV index in September
Shell, WY
- Average UV index in September: 3
The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, March, April, October, November and December (UV index 2).
Average cloud cover in September
Shell, WY
- Average cloud cover in September: 19
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 16).
Average visibility in September
Shell, WY
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (4mi).
