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 commencement of September involves a temperature shift, with the average high-temperature dropping from a moderately hot 78.3°F (25.7°C) in August to a comfortable 67.6°F (19.8°C). During the nights in September, Mammoth records a pronounced shift from the daytime warmth, with a consistent average temperature of 41.2°F (5.1°C).Humidity
In Mammoth, Montana, the average relative humidity in September is 52%.Rainfall
In September, in Mammoth, the rain falls for 10.3 days. Throughout September, 0.98" (25mm) of precipitation is accumulated. In Mammoth, Montana, during the entire year, the rain falls for 158 days and collects up to 12.2" (310mm) of precipitation.Snowfall
In Mammoth, Montana, snow does not fall in May through September.Daylight
In September, the average length of the day in Mammoth is 12h and 31min.On the first day of September in Mammoth, Montana, sunrise is at 6:50 am and sunset at 8:05 pm. On the last day of the month, sunrise is at 7:26 am and sunset at 7:09 pm MDT.
Sunshine
The average sunshine in September in Mammoth, Montana, is 9.8h.UV index
In September, the average daily maximum UV index in Mammoth, Montana, is 3. A UV Index of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A daily high UV index of 3 in September leads to these guidelines:
Take precautions. Light skin individuals may get burned in less than 30 minutes. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. Using UVA and UVB-protective sunglasses and sun-protective clothing is effective against UV radiation.
Frequently asked questions
What are September temperatures in Mammoth?
What is the average humidity in September in Mammoth?
How many days does it rain in September in Mammoth?
When it does not snow in Mammoth?
Does it snow in Mammoth in September?
How many hours of daylight does Mammoth have in September?
What time are sunrise and sunset in September in Mammoth?
How many hours of sunshine does Mammoth have in September?
How high is the UV index in September in Mammoth?
Average temperature in September
Mammoth, MT
- Average high temperature in September: 67.6°F
The warmest month (with the highest average high temperature) is July (79.5°F).
The month with the lowest average high temperature is December (26.4°F).
- Average low temperature in September: 41.2°F
The month with the highest average low temperature is July (47.7°F).
The coldest month (with the lowest average low temperature) is December (11.3°F).
Average pressure in September
Mammoth, MT
- Average pressure in September: 29.99"Hg
The month with the highest atmospheric pressure is January (30.23"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Mammoth, MT
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is November (6.3mph).
The calmest month (with the lowest average wind speed) is August (4.6mph).
Average humidity in September
Mammoth, MT
- Average humidity in September: 52%
The month with the highest relative humidity is January (85%).
The months with the lowest relative humidity are July and August (46%).
Average rainfall in September
Mammoth, MT
- Average rainfall in September: 0.98"
The wettest month (with the highest rainfall) is May (1.85").
The driest month (with the least rainfall) is January (0.59").
Average rainfall days in September
Mammoth, MT
- Average rainfall days in September: 10.3 days
The month with the highest number of rainy days is April (18.6 days).
The month with the least rainy days is August (8.6 days).
Average snowfall in September
Mammoth, MT
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.81").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Mammoth, MT
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (6.2 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Mammoth, MT
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in September: 9h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in September
Mammoth, MT
- Average sunshine days in September: 16.4 days
The month with the most sunshine days is July (17.8 days).
The month with the least sunshine days is April (7.8 days).
Average UV index in September
Mammoth, MT
- 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
Mammoth, MT
- Average cloud cover in September: 19
The month with the most cloud cover is February (Cloud cover 42).
The months with the least cloud cover are July and August (Cloud cover 14).
Average visibility in September
Mammoth, MT
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January, February and December (5mi).
Mammoth, Montana, USA
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