September weather forecastFrenchtown, MT
September
Weather in September
September, the first month of the autumn in Frenchtown, is also an agreeable month, with an average temperature varying between 40.6°F (4.8°C) and 68.7°F (20.4°C).Temperature
During the transition into September, Frenchtown observes a decrease in the average high-temperature, falling from a moderately hot 79.3°F (26.3°C) in August to a pleasant 68.7°F (20.4°C). Frenchtown's nights during September are marked by a pronounced drop from daytime temperatures, experiencing an average low of 40.6°F (4.8°C).Humidity
In September, the average relative humidity is 58%.Rainfall
In September, the rain falls for 10.6 days. Throughout September, 1.14" (29mm) of precipitation is accumulated. Throughout the year, there are 162.6 rainfall days, and 20.12" (511mm) 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 0.2 snowfall days, it receives 0.59" (15mm) of snow. In Frenchtown, during the entire year, snow falls for 98.8 days and aggregates up to 55.2" (1402mm) of snow.Daylight
The average length of the day in September is 12h and 32min.On the first day of the month, sunrise is at 6:57 am and sunset at 8:15 pm. On the last day of September, in Frenchtown, sunrise is at 7:35 am and sunset at 7:17 pm MDT.
Sunshine
In Frenchtown, the average sunshine in September is 9.3h.UV index
In September, the average daily maximum UV index is 3. A UV Index estimate of 3 to 5 represents a medium vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In September, the UV index of 3 transforms into the following advice:
Undertake precautions - It is suggested to shield oneself from sunburn. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Frenchtown, MT
- Average high temperature in September: 68.7°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is December (28°F).
- Average low temperature in September: 40.6°F
The month with the highest average low temperature is August (46.4°F).
The coldest month (with the lowest average low temperature) is December (15.3°F).
Average pressure in September
Frenchtown, MT
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Frenchtown, MT
- Average wind speed in September: 4.2mph
The windiest month (with the highest average wind speed) is April (4.9mph).
The calmest month (with the lowest average wind speed) is August (3.9mph).
Average humidity in September
Frenchtown, MT
- Average humidity in September: 58%
The month with the highest relative humidity is January (91%).
The months with the lowest relative humidity are July and August (51%).
Average rainfall in September
Frenchtown, MT
- Average rainfall in September: 1.14"
The wettest month (with the highest rainfall) is April (2.44").
The driest month (with the least rainfall) is July (0.63").
Average rainfall days in September
Frenchtown, MT
- Average rainfall days in September: 10.6 days
The month with the highest number of rainy days is April (20 days).
The months with the least rainy days are July and August (8.4 days).
Average snowfall in September
Frenchtown, MT
- Average snowfall in September: 0.59"
The month with the highest snowfall is February (12.91").
The months with the least snowfall are June, July and August (0").
Average snowfall days in September
Frenchtown, MT
- Average snowfall days in September: 0.2 days
The month with the highest number of snowfall days is February (19.1 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in September /
Average sunshine in September
Frenchtown, MT
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).
Average sunshine days in September
Frenchtown, MT
- Average sunshine days in September: 17.2 days
The month with the most sunshine days is July (20.3 days).
The month with the least sunshine days is March (6.6 days).
Average UV index in September
Frenchtown, MT
- Average UV index in September: 3
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in September
Frenchtown, MT
- Average cloud cover in September: 24
The month with the most cloud cover is February (Cloud cover 56).
The month with the least cloud cover is July (Cloud cover 15).
Average visibility in September
Frenchtown, MT
- 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 (4mi).
