Idaho Falls in September

8.5out of 10

Yes, a good time to go

Warm and comfortable: highs around 24°C. Some rain: about 4 rainy days.

24°CAvg high
8°CAvg low
4Rainy days (24 mm)
12:17 hDaylight
07:14Sunrise · 19:31 Sunset

Why this score

  • Warm and comfortable: highs around 24°C
  • Some rain: about 4 rainy days

What to wear and pack

  • T-shirts and light layers
  • A light jacket for cooler evenings

How reliable is the forecast?

Rainfall in September is fairly consistent from year to year (2.7 days). Averages cover 30 years (1991–2020). Individual days can differ a lot.

Year at a glance

0° -8° J 3° -6° F 9° -2° M 14° 2° A 20° 6° M 26° 10° J 31° 14° J 30° 13° A 24° 8° S 16° 3° O 6° -3° N 0° -8° D Rainy days

Weather by month

MonthAvg highAvg lowRainfall Rainy daysHumiditySunshine Score
January 0°C-8°C36 mm 10– – 3.8
February 3°C-6°C28 mm 8– – 4.4
March 9°C-2°C36 mm 9– – 5.6
April 14°C2°C45 mm 11– – 6.3
May 20°C6°C53 mm 10– – 7.4
June 26°C10°C31 mm 6– – 8.3
July 31°C14°C12 mm 4– – 8.0
August 30°C13°C14 mm 4– – 8.2
September 24°C8°C24 mm 4– – 8.5
October 16°C3°C33 mm 6– – 7.2
November 6°C-3°C30 mm 8– – 5.2
December 0°C-8°C38 mm 9– – 3.8

Frequently asked questions

How hot is Idaho Falls in September?

Daytime highs average 24°C and nights about 8°C.

When is the best time to visit Idaho Falls?

The best months are September, June, August, July.