Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
Alta experiences a temperature shift at the start of September, with average high-temperatures adjusting from a moderately hot 74.1°F (23.4°C) in August to an enjoyable 64.9°F (18.3°C). Despite the stark contrast with daytime temperatures, Alta's September nights average at a wintry 40.1°F (4.5°C).Humidity
The average relative humidity in September is 54%.Rainfall
In Alta, in September, it is raining for 9.5 days, with typically 1.65" (42mm) of accumulated precipitation. In Alta, during the entire year, the rain falls for 96.6 days and collects up to 32.95" (837mm) of precipitation.Snowfall
January through June, August through December are months with snowfall. In Alta, Wyoming, in September, snow falls for 2.5 days, with typically accumulated 4.49" (114mm) of snow. Throughout the year, there are 160.8 snowfall days, and 200.16" (5084mm) of snow is accumulated.Daylight
The average length of the day in September is 12h and 29min.On the first day of the month, sunrise is at 6:48 am and sunset at 7:59 pm. On the last day of September, sunrise is at 7:21 am and sunset at 7:06 pm MDT.
Sunshine
The average sunshine in September in Alta is 9.9h.UV index
In September, the average daily maximum UV index is 3. A UV Index reading of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: A daily high UV index of 3 in September leads to these guidelines:
Put precautions into practice - Protective measures against sun-induced damage are advised. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat. Be careful! The Sun's UV radiation can nearly be doubled by the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature?
What is the average humidity in September?
How much does it rain in September?
How many days does it snow in September in Alta?
What is the average length of the day in September in Alta?
When is the sunrise / sunset in September?
How many hours of sunshine does Alta have in September?
What is the UV index intensity in September in Alta?
Average temperature in September
Alta, WY
- Average high temperature in September: 64.9°F
The warmest month (with the highest average high temperature) is July (75.4°F).
The month with the lowest average high temperature is December (23.2°F).
- Average low temperature in September: 40.1°F
The month with the highest average low temperature is July (46.9°F).
The coldest month (with the lowest average low temperature) is December (7.7°F).
Average pressure in September
Alta, WY
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.27"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Alta, WY
- Average wind speed in September: 5.6mph
The windiest month (with the highest average wind speed) is June (6.2mph).
The calmest months (with the lowest average wind speed) are January and December (4.8mph).
Average humidity in September
Alta, WY
- Average humidity in September: 54%
The month with the highest relative humidity is February (94%).
The month with the lowest relative humidity is August (47%).
Average rainfall in September
Alta, WY
- Average rainfall in September: 1.65"
The wettest month (with the highest rainfall) is February (4.13").
The driest month (with the least rainfall) is July (0.91").
Average rainfall days in September
Alta, WY
- Average rainfall days in September: 9.5 days
The month with the highest number of rainy days is May (15.5 days).
The month with the least rainy days is January (3 days).
Average snowfall in September
Alta, WY
- Average snowfall in September: 4.49"
The month with the highest snowfall is February (34.33").
The month with the least snowfall is July (0").
Average snowfall days in September
Alta, WY
- Average snowfall days in September: 2.5 days
The month with the highest number of snowfall days is March (23.6 days).
The month with the least snowfall days is July (0.1 days).
Average daylight in September /
Average sunshine in September
Alta, WY
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in September: 9h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is February (Average sunshine: 3h and 18min).
Average sunshine days in September
Alta, WY
- Average sunshine days in September: 16.7 days
The month with the most sunshine days is July (20.3 days).
The month with the least sunshine days is April (6.2 days).
Average UV index in September
Alta, 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, October, November and December (UV index 1).
Average cloud cover in September
Alta, WY
- Average cloud cover in September: 20
The month with the most cloud cover is February (Cloud cover 73).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in September
Alta, WY
- Average visibility in September: 6mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February, March and December (3mi).
Alta, Wyoming, USA
Weather forecast for your location
2. Allow the app to use your location