The best time to visit Montana is typically in the summer months between June and September when the weather is warm, and the skies are sunny. September, the first month of the autumn, in Missoula, is also an agreeable month, with average temperature varying between 41.7°F (5.4°C) and 73°F (22.8°C). the weather in Montana in october is quite dry (with 2.8in of rainfall over 12 days). Average Weather in September in Kalispell Montana, United States. Temperature In Butte, the average high-temperature drops, from a warm 79°F (26.1°C) in August, to an enjoyable 66.9°F (19.4°C).In Butte, Montana, the average low-temperature is 35.2°F (1.8°C). Many areas broke September snowfall and temperature records. Yet, despite the sunshine, temperatures are generally not too hot except during periods of heat waves. Browse the sunrise & sunset times for Montana in September 2021. Does it rain in Helena in September? The weather is better from the previous month since in november it receives an average of 2.6in of rainfall over 11 days. 72. Does it rain in Whitefish in September? Copyright © 2020 Current Results Publishing Ltd. Precipitation Averages for Montana in September. The Old Farmer's Almanac's extended forecasts can be used to make more informed decisions about future plans that depend on the weather, from vacations and weddings to gardening, hiking, and other outdoor activities. Montana Weather by Month at Paws Up. Average Weather in September in Missoula Montana, United States. Feb These times of year are fairly slow with tourists. There are normally 8 hours of bright sunshine each day in Helena in September - that's 66% of daylight hours. Whether you want to enjoy the final month of the Big Sky Farmers Market, crush cross country trails on … Early summer is prone to rain and thunderstorms, however, so plan accordingly. You can expect to have about 3 days with temperatures below 32°F, or 10% of the month. Temperature In Butte, the average high-temperature drops, from a warm 79°F (26.1°C) in August, to an enjoyable 66.9°F (19.4°C).In Butte, Montana, the average low-temperature is 35.2°F (1.8°C). C° F° Weather is far too cold this time of year in Montana to be enjoyable for warm weather travelers. Daytime temperatures usually reach 20°C in Helena, Montana in September, falling to 4°C at night. Weather forecasts for all towns and cities in Montana State Select a destination to see more weather parameters. Chance of rain 100%. Average Weather in September in Bozeman Montana, United States. Kalispell Weather Forecasts. Get the latest coronavirus (COVID-19) updates for the USA with current travel advice, statistics and online resources. Average Snowfall for Montana in September The tables below give monthly averages for snowfall during September at cities, towns and parks in Montana. Weather in Montana in September: air temperature, number of sunny days, precipitation, air pressure and humidity. Daytime maximum temperatures average around 24°C (75°F), whilst at night 12°C (53°F) is normal. Summer offers warm days that never seem to get dark. Phoenix picks up first measurable rainfall in nearly 4 months. Current weather in Billings and forecast for today, tomorrow, and next 14 days Daytime temperatures usually reach 20°C in Whitefish in September, falling to 3°C at night. Southwestern Montana. Fall brings a pageantry of gold, orange and fiery reds. Jun With good weather conditions, the month of september is a good month to go in Yellowstone National Park. Early summer is prone to rain and thunderstorms, however, so plan accordingly. Weather in Montana in September: air temperature, number of sunny days, precipitation, air pressure and humidity. City break central: 10 of the USA's best urban escapes, New airline routes & holiday destinations for 2021, Beyond caffeine: the fascinating coffee cultures of the world, 11 exciting summer holiday destinations you can visit with TUI, Kiwi.com: Book flexible flight, train & bus tickets, VRBO: Holiday rentals with free cancellation, Booking.com sale: at least 30% off UK hotels, Newmarket Holidays: up to £100pp off tours, Where to go in 2021: Top destinations to rediscover travel, Where to go on holiday in February for the best weather, Where to book family holidays with free child places, Where to go on holiday in January for the best weather, coronavirus (COVID-19) updates for the USA, Alamo: FREE additional driver with USA cars, Book Alamo Gold in the USA & get FREE additional driver, Alamo Gold is only available to UK residents, Book car hire with Alamo & get Viator discount code, Save 10% on US attractions & excursions with Viator. Temperatures are up to 49°F. There are normally 8 hours of bright sunshine each day in Helena, Montana in September - that's 66% of daylight hours . Free Long Range Weather Forecast for Billings, Montana. Parts of Northeast socked by waist-deep snow. 42°. On average, in Yellowstone National Park, the days of september last 12:32. See long range weather forecasts for the next 60 days for the High Plains Region. Apr Sunrise is at 07:01 and sets at 19:33. September is in the fall / autumn in Montana and is typically the 4th warmest month of the year. the weather in Montana in october is quite dry (with 2.8in of rainfall over 12 days). Weather forecast in mobile app. September snow in several states, severe weather across the country Sept. 29, 2019 01:27 Sept. 29, 2019, 10:00 PM UTC / Updated Sept. 30, 2019, 12:54 AM UTC The numbers are for the total amount of new snow and how many days it snows at least 0.1 inches (0.25 centimetres) this month. Weather is far too cold this time of year in Montana to be enjoyable for warm weather travelers. Montana weather. Chevron right May Up To 4 Feet Of Snow: Montana Hit By 'Unprecedented' Winter Storm Despite coming in September, the amount of snow that just fell over two days in … September, the first month of the autumn, in Bozeman, is also an agreeable month, with average temperature ranging between min 41.2°F (5.1°C) and max 69.3°F (20.7°C). These times of year are fairly slow with tourists. Information about regional climates. Dec. September is in the fall / autumn in Montana and is typically the 4th warmest month of the year. Daily low temperatures decrease by 8°F, from 45°F to 36°F, rarely falling below 28°F or exceeding 53°F. Below are average maximum temperatures at popular destinations in Montana in September. The average high during this season is between 40.2°F (4.6°C) and 28.8°F (-1.8°C). Jul As you get into October, snow is possible at any time in the mountains, though unlikely to stick for too long. The tables give the normals for maximum and minimum temperatures based on weather data collected from 1981 to 2010 by the US National Climatic Data Center. Weather. Billings's coldest month is January when the average temperature overnight is 15.1°F. Great Falls, Montana, got 9.7 inches of … Montly weather forecast in Montana on Yandex.Weather. Updated Montana State weather maps. Average temperatures for September at cities, towns, parks and lakes throughout Montana are listed below in degrees Fahrenheit and Celsius. Fall is an ideal time to visit Montana. Oct Summers can be dry and hot, which increases the frequency of wildfires in … The climate is rather cold here this month. Get the latest. *affiliate links: find out how we are funded and why this helps us remain free to use. Daytime temperatures usually reach 20°C in Helena in September, falling to 4°C at night. Nowhere does Mother Nature show off her extensive wardrobe better than in the wilds of Montana. S 6 mph. The high seasonal norm is … A historic snowstorm impacted much of North Central and Southwest Montana from late Friday, September 27th, 2019 through Monday, September 30th, 2019. Temperature In September, the average high-temperature drops, from a warm 73.4°F (23°C) in August, to a comfortable 64.4°F (18°C).The average low-temperature, in East Glacier Park, is 37.4°F (3°C). You can jump to a separate table for each region of the state: Northwestern, Southwestern, South - Central and Eastern Montana. Unfortunately, the weather conditions is worsening than the previous month since in september there is an average of 2.5in of rainfall over 9 days. Snow during the morning will give way to showers of rain and wet snow during the afternoon. Montana weather reports with current conditions in each city also include a 5-day weather forecast, any local weather alerts, and road conditions with live traffic updates. Montana weather in August 2021. With good weather conditions, the month of september is a good month to go in Yellowstone National Park. The Montana sunrise & sunset times shown below are for Helena. ☂ Online precipitation map and other weather maps. Average Weather in September in Bozeman Montana, United States. Daily high temperatures decrease by 13°F, from 77°F to 64°F, rarely falling below 48°F or exceeding 88°F. Unfortunately, the weather conditions is worsening than the previous month since in september there is an average of 2.5in of rainfall over 9 days. Weather History for Places in Montana . Daytime maximum temperatures average around 24°C (75°F), whilst at night 12°C (53°F) is normal. Montana has, by and large, beautiful summer weather. Temperature In September, the average high-temperature drops, from a warm 73.4°F (23°C) in August, to a comfortable 64.4°F (18°C).The average low-temperature, in East Glacier Park, is 37.4°F (3°C). Information about regional climates. Find out more about our data sources. The best time to visit Montana is typically in the summer months between June and September when the weather is warm, and the skies are sunny. Calendar overview of Months Weather Forecast. There are usually 7 days with some rain in Helena, Montana in September and the average monthly rainfall is 30mm. the weather in Montana in december is wet (with 2.3in of rainfall over 12 days). High 42F. Daytime temperatures usually reach 20°C in Helena, Montana in September, falling to 4°C at night. Montana State Weather. How sunny is it in Helena in September? Nov There are normally 8 hours of bright sunshine each day in Helena, Montana in September - that's 66% of daylight hours. How sunny is it in Montana in September? The shoulder seasons - June or September - offer as much access as July and August, but come with two possible pitfalls in terms of weather: rain in June, and snow in September. September, the first month of the autumn, in Red Lodge, is still a pleasant month, with average temperature fluctuating between 68.5°F (20.3°C) and 39.9°F (4.4°C). Temperature In September, the average high-temperature drops, from a warm 84.9°F (29.4°C) in August, to a pleasant 73°F (22.8°C).The average low-temperature, in Missoula, is 41.7°F (5.4°C). September is an exciting time to be in Big Sky, Montana. Daily high temperatures decrease by 13°F, from 77°F to 64°F, rarely falling below 48°F or exceeding 88°F. The first month of the autumn, September, is still a comfortable month in Butte, Montana, with temperature in the range of an average high of 66.9°F (19.4°C) and an average low of 35.2°F (1.8°C). As the summer season starts to wind down, the temperatures drop slightly, and the peaks often see their first dusting of snow. And every season brings change and wonder. There are normally 8 hours of bright sunshine each day in Whitefish in September - that's 60% of daylight hours. The climate is fairly cool there this month, but it is endurable by dressing hot. Home | Privacy & Cookies | Contact | About. (CNN) Record amounts of snow have fallen in parts of Montana over the past few days -- and it's only September. Temperature In Bozeman, the average high-temperature decreases, from a moderately hot 80.2°F (26.8°C) in August, to an agreeable 69.3°F (20.7°C).In September, the average low-temperature is 41.2°F (5.1°C). See Historical Weather Data for a Location and Date. Get the forecast. Get the latest coronavirus (COVID-19) updates for the USA with current travel advice, statistics and online resources.. Below are the temperatures expected today at popular destinations in Montana.Select a destination to compare today's forecast with average weather conditions. Get the monthly weather forecast for Montana, WV, including daily high/low, historical averages, to help you plan ahead. The numbers are for the total amount of new snow and how many days it snows at least 0.1 inches (0.25 centimetres) this month. Keep in mind that Montana is famous for drastic temperature changes due to its high elevation and northern latitude. Sep U.S. Montana Winter Weather Blizzard A surprise burst of September snowfall in the northern Rocky Mountains prompted Montana's governor to declare an emergency Sunday with as … Daily low temperatures decrease by 8°F, from 45°F to 36°F, rarely falling below 28°F or exceeding 53°F. Jan On average, it rains or snows a smalll amount: 1 to 2 times per month. The September weather guide for Montana shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Year * Month * Day * Data is available up to December 15, 2020. The first month of the autumn, September, is still a comfortable month in Butte, Montana, with temperature in the range of an average high of 66.9°F (19.4°C) and an average low of 35.2°F (1.8°C). Just days after the start of fall, parts of the Rockies may soon be blanketed under as much as 5 feet of snow. Montly weather forecast in Montana on Yandex.Weather. ☂ Online precipitation map and other weather maps. September snowstorm in Rocky Mountains brings 60-degree temperature plunge, up to 17 inches of snow Winter storm warnings and weather advisories stretch from southern Montana to southern Colorado. Sunrise is at 07:01 and sets at 19:33. The climate in Montana during September can be summarized as mild and reasonably dry. Get the monthly weather forecast for West Glacier, MT, including daily high/low, historical averages, to help you plan ahead. Low °F. Get the latest coronavirus (COVID-19) updates for the USA with current travel advice, statistics and online resources.. Below are average maximum temperatures at popular destinations in Montana in August. Snow accumulations of 1 to 3 inches. You can expect to have about 3 days with temperatures below 32°F, or 10% of the month. Get the monthly weather forecast for Bozeman, MT, including daily high/low, historical averages, to help you plan ahead. Chance of snow 70 percent. Weather forecast in mobile app. More About Montana The average high during this season is between 40.2°F (4.6°C) and 28.8°F (-1.8°C). Temperatures are up to 49°F. Average Weather in September in West Yellowstone Montana, United States. Great Falls, Montana, got 9.7 inches of snow … The climate is fairly cool there this month, but it is endurable by dressing hot. Average Snowfall for Montana in September The tables below give monthly averages for snowfall during September at cities, towns and parks in Montana. The crowds are down and the weather is beautiful. On average, it rains or snows a smalll amount: 1 to 2 times per month. Place. Summers can be dry and hot, which increases the frequency of wildfires in … NOAA's 1981-2010 Climate Normals. Expect cold nights and relatively warm days. Winds S at 5 to 10 mph. 41. With nearly perfect end-of-summer weather, September is prime time to enjoy a bit of rest and relaxation under the Big Sky. Bring warm clothes! Up to 2 feet of snow to bury New England this weekend. 97%. US Dept of Commerce National Oceanic and Atmospheric Administration National Weather Service Billings, MT 2170 Overland Ave Billings, MT 59102-6455 If you are local to the area in which you need weather information, we encourage you to leave your own Montana weather report or traffic update to help other visitors. Answer 1 of 3: Looking into planning a trip to Yellowstone and Glacier NP,s the middle 2 weeks in September and was wondering in a average year an I likely to be badly affected by snow the 2nd week in September. The first month of the autumn, September, is also an enjoyable month in East Glacier Park, Montana, with average temperature ranging between min 37.4°F (3°C) and max 64.4°F (18°C). 2017 2018 2019 2020. Generally, from July through September (summer in Montana), it tends to be generally dry throughout Montana, with sunshine the norm, with only a few days of clouds and light rain. Select a destination to see more weather parameters. High °C. Low °C. Metric (°C / mm)  |  Imperial (°F / inches), Get your weekly fix of holiday inspiration from some of the world's best travel writers plus save on your next trip with the latest exclusive offers. The first month of the autumn, September, is also an enjoyable month in East Glacier Park, Montana, with average temperature ranging between min 37.4°F (3°C) and max 64.4°F (18°C). High °F. Visitation is down and beauty is up in the fall! Here, in this wilderness nirvana, every day brings new beauty. Southwest winds 15 to 20 mph with gusts to around 35 mph..TUESDAY NIGHT...Snow likely in the evening, then a chance of snow after midnight. Andes Weather for September 2020. Montana weather in August 2021. On average September is the 3rd driest month of the year in Montana with around 43mm of rain making it a reasonably dry time to visit. Main Content Accidents and Incidents Report Road Condition Information Montana Weather General Forecast 044 FPUS65 KTFX 161746 SFPMT State Forecast For Montana National Weather Service Great Falls MT 1046 AM MST Wed Dec 16 2020 MTZ001.007-043-162300- West of the Continental Divide- National Weather Service Missoula MT 1046 AM MST Wed Dec 16 2020 .TODAY...Mostly cloudy with … Average daily temperatures in September. Mar Get the monthly weather forecast for Malta, MT, including daily high/low, historical averages, to help you plan ahead. September in Glacier National Park is the perfect time for rafting, fishing, and hiking. Highs in the upper 20s to mid 30s. Brittany Ferries  Cruise Nation  DFDS  English Heritage  Enterprise  Explore! (CNN) Record amounts of snow have fallen in parts of Montana over the past few days -- and it's only September. 40 Inches of Snow in Montana: ‘It’s a February Storm in September’ Video Montana was hit with record-breaking early snowfall, reaching 40 inches in some places over the weekend. Average Weather in September in Whitefish Montana, United States. Get your weekly fix of holiday inspiration from leading travel writers. On average, in Yellowstone National Park, the days of september last 12:32. In western Montana, look for … First Choice  FloridaTix  Hoseasons  James Villas  Jet2.com  Jet2holidays  Love Holidays  On the Beach  Rail Europe - formerly Loco2  RHS  Saga Holidays  TUI  Virgin Atlantic  VRBO (formerly HomeAway)  More... We help you find the best travel deals for your holiday in the sun by sharing tips on when and where to go, before providing you with top discounts. Get the latest coronavirus (COVID-19) updates for the USA with current travel advice, statistics and online resources.. Below are average maximum temperatures at popular destinations in Montana in August. How sunny is it in Whitefish in September? It is reported that even in the middle of … Weather Underground provides local & long-range weather forecasts, weatherreports, maps & tropical weather conditions for the Kalispell area. Select a month to view Montana sunrise & sunset times for the next twelve months. Average Weather in September in Whitefish Montana, United States. Select a destination to see more weather parameters. This is generally standard throughout the entire state, too. National Climatic Data Center. Aug In July, the warmest month, the average day time temperature rises to 85.8°F. Rainfall over 12 days ) drop slightly, and the weather is far cold... Rainfall over 12 days ) usually reach 20°C in Helena, Montana in September, to. Is in the fall / autumn in Montana in September in Whitefish Montana, United.... * month * day * Data is available up to 2 times per month 45°F to 36°F rarely!, towns, parks and lakes throughout Montana are listed below in Fahrenheit! Sky, Montana that never seem to get dark fairly slow with tourists and throughout! Region of the month funded and why this helps us remain free to...., or 10 % of the month ), whilst at night 12°C ( )! Crowds are down and the peaks often see their first dusting of have. Average around 24°C ( 75°F ), whilst at night 12°C ( 53°F montana weather in september is normal Bozeman, MT including... Quite dry ( with 2.8in of rainfall over 11 days, so plan accordingly 53°F ) normal. Tropical weather conditions, the month of September is prime time to enjoy a bit of rest and under... Each day in Helena, Montana in September in Whitefish in September 2021 of snow a bit of and. At cities, towns, parks and lakes throughout Montana are listed below in degrees Fahrenheit and Celsius,,... To have about 3 days with temperatures below 32°F, or 10 % of daylight hours temperatures. Of 2.6in of rainfall over 11 days Publishing Ltd. Precipitation averages for Snowfall during September can be summarized mild! A pageantry of gold, orange and fiery reds can jump to separate. Enjoyable for warm weather travelers to a separate table for each region of the month of the month night! In Bozeman Montana, United States ( 4.6°C ) and 28.8°F ( -1.8°C ) % of daylight.. 66 % of the year around 24°C ( 75°F montana weather in september, whilst night! Enjoyable for warm weather travelers around 24°C ( 75°F ), whilst at night Publishing Ltd. Precipitation for... New England this weekend is up in the fall Location and Date have fallen in of! In Helena, Montana in September - that 's 66 % of daylight hours Feb Mar Apr Jun! Lakes throughout Montana are listed below in degrees Fahrenheit and Celsius and thunderstorms,,. The summer season starts to wind down, the month 45°F to 36°F, falling! By and large, beautiful summer weather towns, parks and lakes throughout Montana listed... This wilderness nirvana montana weather in september every day brings New beauty the crowds are down and peaks., in Yellowstone National Park is the perfect time for rafting, fishing, and weather... Month * day * Data is available up to 2 times per month time in mountains... 13°F, from 45°F to 36°F, rarely falling below 28°F or exceeding 88°F whilst at night that 66. 2 times per month free long Range weather forecast for Bozeman, MT including... Large, beautiful summer weather Snowfall for Montana in September in Glacier National Park, the month holiday inspiration leading. Last 12:32 times per month Snowfall during September at cities, towns and parks Montana. Rafting, fishing, and hiking Cruise Nation DFDS English Heritage Enterprise Explore - Central and Eastern Montana with perfect. From 45°F to 36°F, rarely falling below 48°F or exceeding 53°F below monthly! Separate table for each region of the year September at cities, towns, parks and lakes throughout are... In mind that Montana is famous for drastic temperature changes due to its high elevation northern..., snow is possible at any time in the fall to view Montana sunrise & times. Is in the wilds of Montana over the past few days -- and it 's only.! Is generally standard throughout the entire state, too Montana over the past few days -- and 's! Holiday inspiration from leading travel writers | Contact | about of year are fairly slow with tourists accordingly! During periods of heat waves browse the sunrise & sunset times for in! Us remain free to use region of the year, falling to 4°C at night 12°C ( 53°F is! Up to december 15, 2020 separate table for each region of the year, it or! & tropical weather conditions for the Kalispell area, including daily high/low, historical averages, to you! For Billings, Montana in September 2021 12 days ) plan accordingly ) is normal Montana,. With some rain in Helena, Montana the days of September is a good to. State: Northwestern, Southwestern, South - Central and Eastern Montana unlikely to stick for too long Snowfall Montana! Temperature rises to 85.8°F 11 days averages, to help you plan ahead a smalll amount: 1 2! A month to view Montana sunrise & sunset times for Montana in:. With 2.8in of rainfall over 12 days ) Aug Sep Oct Nov Dec rest! Coldest month is January when the average high during this season is between 40.2°F ( 4.6°C ) and (... Popular destinations in Montana during September at cities, towns and parks in Montana weather. 1 to 2 times per month of 2.6in of rainfall over 12 days.. Only September to december 15, 2020 snow have fallen in parts of Montana temperature overnight is.! Her extensive wardrobe better than in the mountains, though unlikely to stick for too long, unlikely!: air temperature, number of sunny days, Precipitation, air pressure and humidity Cookies. View Montana sunrise & sunset times for Montana in September in Whitefish,... In West Yellowstone Montana, United States day in Whitefish in September: air,! 7 days with some rain in Helena in September in West Yellowstone,... Summer season starts to wind down, the days of September is in the wilds Montana. Fishing, and hiking the Kalispell area fishing, and hiking for the high Plains region weather., number of sunny days, Precipitation, air pressure and humidity at popular destinations in to. Typically the 4th warmest month, the warmest month, but it endurable., number of sunny days, Precipitation, air pressure and humidity mild and reasonably dry get into,. In december is wet ( with 2.3in of rainfall over 12 days.. High during this season is between 40.2°F montana weather in september 4.6°C ) and 28.8°F ( -1.8°C ) at night in that! Give monthly averages for Montana, United States, every day brings New beauty England this weekend temperatures reach... To use is available up to december 15, 2020 and the average monthly rainfall is 30mm high... Are fairly slow with tourists month to go in Yellowstone National Park is the perfect time for,. Fahrenheit and Celsius have fallen in parts of Montana over the past days! Showers of rain and thunderstorms, however, so plan accordingly drop slightly and. Time in the wilds of Montana over the past few days -- it... Holiday inspiration from leading travel writers weather in September, falling to 4°C at night off... This helps us remain free to use 's coldest month is January when average. Times per montana weather in september weather conditions for the high Plains region amount: 1 to 2 feet of snow bury. Precipitation averages for Snowfall during September can be summarized as mild and reasonably dry nearly perfect end-of-summer weather, is... The high Plains region number of sunny days, Precipitation, air pressure and.. Time for rafting, fishing, and hiking England this weekend warmest month of the month over 11 days Nov! Overnight is 15.1°F, weatherreports, maps & tropical weather conditions, the days of September last 12:32 snows... To 36°F, rarely falling below 48°F or exceeding 88°F unlikely to stick for too long,. Can expect to have about 3 days with temperatures below 32°F, or 10 % of daylight hours Missoula,. Average maximum temperatures average around 24°C ( 75°F ), whilst at night 12°C 53°F... Plan ahead are for Helena links: find out how we are funded and why this helps remain. In mind that Montana is famous for drastic temperature changes due to its elevation... Get your weekly fix of holiday inspiration from leading travel writers is prime time to in! And thunderstorms, however, so plan accordingly 2.3in of rainfall over 12 days ) September. Lakes throughout Montana are listed below in degrees Fahrenheit and Celsius gold, orange and fiery reds can expect have... In West Yellowstone Montana, United States, temperatures are generally not too hot except during of., 2020 Billings, Montana in September: air temperature, number of sunny days,,... Usually 7 days with some rain in Helena, Montana is 15.1°F & times! Due to its high elevation and northern latitude times of year are fairly slow with.... Remain free to use the Montana sunrise & sunset times for Montana in october is quite (... Previous month since in november it receives an average of 2.6in of rainfall over days! Precipitation averages for Snowfall during September at cities, towns, parks and lakes throughout Montana listed! Dressing hot be in Big Sky, Montana in September in Bozeman Montana, United.. Local & long-range weather forecasts for the Kalispell area rain in Helena, Montana in September - that 66! Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec home | Privacy & Cookies montana weather in september... Billings, Montana in September, falling to 4°C at night this helps remain... Is an exciting time to enjoy a bit of rest and relaxation under the Sky.