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
The arrival of September indicates a decrease in the average high-temperature, moving from a warm 82.2°F (27.9°C) in August to an agreeable 70.9°F (21.6°C). The mean low-temperature during September nights in Hays is a fresh 53.4°F (11.9°C).Humidity
In Hays, the average relative humidity in September is 46%.Rainfall
In Hays, in September, during 8.7 rainfall days, 1.1" (28mm) of precipitation is typically accumulated. Throughout the year, there are 103.3 rainfall days, and 11.81" (300mm) of precipitation is accumulated.Snowfall
Months with snowfall in Hays are January through May, September through December. September is the first month it typically snows in Hays. Throughout September, in the average 0.2 snowfall days, it receives 0.2" (5mm) of snow. In Hays, during the entire year, snow falls for 59.6 days and aggregates up to 20.28" (515mm) of snow.Daylight
The average length of the day in September is 12h and 33min.On the first day of September, sunrise is at 6:33 am and sunset at 7:55 pm. On the last day of the month, sunrise is at 7:13 am and sunset at 6:55 pm MDT.
Sunshine
The average sunshine in September in Hays, Montana, is 9.9h.UV index
The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: In September, the maximum UV index of 4 suggests these recommendations:
Be vigilant - Preventing sunburn is recommended. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Boost your sun resistance with garments that are densely woven yet spacious. Take warning! The intensity of the Sun's UV radiation can be nearly amplified twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Hays in September?
What is the average humidity in September in Hays?
How many days does it rain in September in Hays?
When does it start to snow in Hays?
What is the average length of the day in September in Hays?
When are sunrise and sunset in September in Hays?
How many hours of sunshine does Hays have in September?
How high is the UV index in September in Hays?
Average temperature in September
Hays, MT
- Average high temperature in September: 70.9°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The months with the lowest average high temperature are January and February (25.7°F).
- Average low temperature in September: 53.4°F
The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (11.8°F).
Average pressure in September
Hays, MT
- Average pressure in September: 29.92"Hg
The month with the highest atmospheric pressure is February (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in September
Hays, MT
- Average wind speed in September: 9.9mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is February (8.8mph).
Average humidity in September
Hays, MT
- Average humidity in September: 46%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (41%).
Average rainfall in September
Hays, MT
- Average rainfall in September: 1.1"
The wettest months (with the highest rainfall) are May and June (1.89").
The driest months (with the least rainfall) are February and December (0.55").
Average rainfall days in September
Hays, MT
- Average rainfall days in September: 8.7 days
The month with the highest number of rainy days is May (14.1 days).
The month with the least rainy days is December (4 days).
Average snowfall in September
Hays, MT
- Average snowfall in September: 0.2"
The month with the highest snowfall is December (3.9").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Hays, MT
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is December (12.7 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Hays, MT
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in September: 9h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Hays, MT
- Average sunshine days in September: 19.6 days
The month with the most sunshine days is September (19.6 days).
The month with the least sunshine days is April (13.4 days).
Average UV index in September
Hays, MT
- Average UV index in September: 4
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in September
Hays, MT
- Average cloud cover in September: 24
The month with the most cloud cover is February (Cloud cover 49).
The months with the least cloud cover are July and August (Cloud cover 17).
Average visibility in September
Hays, MT
- Average visibility in September: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Hays, Montana, USA
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