Helena weather in September 2025

Expect 20°C daytime maximum temperatures in the shade with on average 8 hours of sunshine per day in Helena in September. Check more long-term weather averages for Helena in September before you book your next holiday to Montana in 2025/2026.

  • 20°C maximum daytime temperature in September in Helena20
    20°C max day temperature
  • 8 hours of sunshine per day
  • 7 days with some rainfall in September in Helena7
    7 days with some rainfall
  • 4°C minimum night-time temperature in September in Helena4
    4°C min night temperature
  • 13 hours of daylight per day in September in Helena13
    13 hours of daylight per day
  • No heat & humidity in September in Helena0
    No heat & humidity
  • 30 mm monthly rainfall in September in Helena30
    30 mm of monthly rainfall
  • UV (maximum) index 5 (Moderate) in September in Helena5
    5 (Moderate) UV index

More about Helena

Helena by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for Montana

Holiday Autos discount code: up to 10% off global car hire

  • Save up to 10% on cheap car hire worldwide
  • Exclusive Holiday Autos discount code automatically applied
  • Travel before 31st December 2024 (inclusive)
Show discount codeShow discount code ******vel
Redeem Holiday Autos discount code >>

Expires at 23:59 on Tuesday 31st Dec 2024 · View all Holiday Autos offers

Holiday AutosCar hire finder

The September weather guide for Montana (Helena) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C / mm)  |  Imperial (°F / inches)

Back to top

More about the USA

How hot is it in Helena in September?

Daytime temperatures usually reach 20°C in Helena in September, falling to 4°C at night.

How sunny is it in Helena in September?

There are normally 8 hours of bright sunshine each day in Helena in September - that's 66% of daylight hours.

Does it rain in Helena in September?

There are usually 7 days with some rain in Helena in September and the average monthly rainfall is 30mm.

Helena September sunrise & sunset times

Browse the sunrise and sunset times for Helena in September 2025. Select a month to view Helena sunrise and sunset times for the next 12 months.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Monday, 1st September 2025 05:49 19:06
Monday, 15th September 2025 06:06 18:39
Tuesday, 30th September 2025 06:26 18:09

Related posts

Popular travel offers

Explore holidays in the sun for less

More holidays

Airport parking

More parking

Airport lounges

More lounges

Top ^