Helena Weather in September

September in Helena averages 22°C (72°F) during the day and 6°C (43°F) at night. The perfect conditions and moderate rainfall make it a solid month to visit.

Rainfall in Helena in September

Typically, about 9 days will experience rainfall, with an average of 34 mm (1.3 in) for the month. A fairly balanced picture this month, some wet days but nothing too extreme in terms of intensity.

Temperature in Helena in September

Helena in September has perfect weather. Days reach 22°C (72°F) and nights cool to 6°C (43°F). This gives the month a fairly typical daily rhythm, with warmer afternoons and more comfortable nights. Nights fall to 6°C (43°F), which is cold enough to feel it indoors too. A good thick duvet makes all the difference for a comfortable night's sleep.

Sunshine in Helena in September

Expect a lot of sunshine this month, with about 254 hours of sun. These sunny conditions add to the overall experience.

If you're a fan of comfortable temperatures and drier conditions, September is a great time to visit.

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Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our Helena's climate page.

Helena Temperature in September

Min Temperature 6°C (43°F)  

Max Temperature 22°C (72°F)  

Chance of Rain 31%  

Precipitation 34 mm (1.3 in)  

Rainy days 9 days  

Humidity 54%  

Sunshine 254 hours  

Percentage Sunshine 68%  

What to Wear in Helena in September

Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Light rain is possible, so consider bringing a small umbrella or rain jacket. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.

What To Do in Helena in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Cycling

10/10

Walking

10/10

Barbeque

9/10

Camping

5/10

Outdoor sports

10/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United States of America, check out our Helena's climate page.

More climate data for Helena

Temperature Rainfall Sunshine Humidity

See the full Helena climate overview or explore weather in the United States of America.