American Falls climate

American Falls Weather in September

NOAA 1991-2020 normals for American Falls 6 Ne, 8.2 km from American Falls

Average highs run from 81°F on September 1 to 68°F on September 30, and lows from 49°F to 40°F. Normal precipitation for the month is 0.81 in over about 4 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at American Falls, in °F, with the record for each date.020406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
75°F
Average low
45°F
Precipitation
0.81 in
Snowfall
0.1 in
Record high
102°FSep 3, 2022
Record low
19°FSep 20, 1983
Chance of a freeze
42%
Days of 90°F or more
0.9
Daylight
13 h 10 min to 11 h 46 min
Cloud cover
43%
Humidity
38%
Dew point
33°F
Wind
7.8 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 181°F49°F96°F 201929°F 200614%0%
Sep 281°F49°F96°F 194731°F 200614%0%
Sep 380°F48°F102°F 202231°F 196414%0%
Sep 480°F48°F97°F 202231°F 196514%0%
Sep 580°F48°F100°F 202032°F 199414%0%
Sep 679°F47°F101°F 202229°F 199614%0%
Sep 779°F47°F100°F 202228°F 201014%0%
Sep 878°F47°F95°F 199429°F 200114%0%
Sep 978°F47°F95°F 202127°F 202014%0%
Sep 1078°F46°F94°F 202130°F 201614%0%
Sep 1177°F46°F95°F 199031°F 198914%0%
Sep 1277°F46°F94°F 195324°F 201414%0%
Sep 1376°F45°F94°F 194826°F 194914%0%
Sep 1476°F45°F97°F 199026°F 196114%0%
Sep 1575°F45°F96°F 200029°F 197015%0%
Sep 1675°F44°F94°F 200028°F 196515%0%
Sep 1775°F44°F94°F 201426°F 196515%0%
Sep 1874°F44°F92°F 197923°F 196515%0%
Sep 1974°F44°F90°F 195621°F 196515%0%
Sep 2073°F43°F89°F 202219°F 198314%0%
Sep 2173°F43°F88°F 196622°F 198314%1%
Sep 2272°F43°F92°F 196623°F 199514%1%
Sep 2372°F42°F90°F 200124°F 199614%1%
Sep 2471°F42°F91°F 200122°F 200014%1%
Sep 2571°F42°F93°F 201523°F 197014%1%
Sep 2670°F42°F90°F 201027°F 197014%1%
Sep 2770°F41°F89°F 200126°F 196414%1%
Sep 2869°F41°F92°F 202422°F 199914%1%
Sep 2969°F41°F89°F 198919°F 198514%1%
Sep 3068°F40°F90°F 195719°F 198514%1%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at American Falls, in percent, and of at least 0.1 inch of snowfall.0510151102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

September 1
sunrise 6:56 AM, sunset 8:06 PM
September 30
sunrise 7:28 AM, sunset 7:14 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00100227 (American Falls 6 Ne), public domain. Records: NOAA GHCN-Daily, station USW00024156, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.