Bonneville County climate

Bonneville County Weather in September

NOAA 1991-2020 normals for Idaho Falls 16 Se, 14.5 km from Bonneville County

Average highs run from 75°F on September 1 to 63°F on September 30, and lows from 44°F to 36°F. Normal precipitation for the month is 1.38 in over about 5 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 Bonneville County, in °F, with the record for each date.020406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
70°F
Average low
40°F
Precipitation
1.38 in
Record high
100°FSep 3, 2022
Record low
18°FSep 20, 1983
Chance of a freeze
94%
Daylight
13 h 10 min to 11 h 46 min
Cloud cover
44%
Humidity
52%
Dew point
33°F
Wind
5.6 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 175°F44°F96°F 202232°F 196518%0%
Sep 275°F44°F96°F 195033°F 197518%0%
Sep 375°F44°F100°F 202230°F 196418%0%
Sep 474°F43°F97°F 202231°F 196518%0%
Sep 574°F43°F97°F 202033°F 196518%0%
Sep 674°F43°F99°F 202231°F 201019%0%
Sep 773°F43°F99°F 202230°F 199219%0%
Sep 873°F42°F92°F 202129°F 200119%0%
Sep 972°F42°F95°F 202126°F 196219%0%
Sep 1072°F42°F95°F 195929°F 202019%0%
Sep 1172°F42°F93°F 199032°F 196419%0%
Sep 1271°F41°F91°F 199024°F 201419%0%
Sep 1371°F41°F91°F 194829°F 198919%0%
Sep 1471°F41°F94°F 199028°F 199319%0%
Sep 1570°F40°F91°F 200026°F 197019%1%
Sep 1670°F40°F89°F 200029°F 196520%1%
Sep 1769°F40°F90°F 201424°F 196520%1%
Sep 1869°F40°F90°F 195621°F 196520%1%
Sep 1968°F39°F90°F 195622°F 196520%1%
Sep 2068°F39°F86°F 202218°F 198320%1%
Sep 2168°F39°F86°F 196622°F 198320%1%
Sep 2267°F38°F87°F 196625°F 197120%1%
Sep 2367°F38°F88°F 198723°F 198520%1%
Sep 2466°F38°F88°F 198718°F 200020%1%
Sep 2566°F37°F89°F 200121°F 197020%1%
Sep 2665°F37°F87°F 196326°F 197020%1%
Sep 2765°F37°F86°F 196924°F 196420%1%
Sep 2864°F36°F89°F 202418°F 199920%1%
Sep 2964°F36°F89°F 195718°F 198520%1%
Sep 3063°F36°F90°F 195718°F 198520%2%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Bonneville County, in percent, and of at least 0.1 inch of snowfall.05101520251102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

September 1
sunrise 6:51 AM, sunset 8:01 PM
September 30
sunrise 7:23 AM, sunset 7:09 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00104456 (Idaho Falls 16 Se), public domain. Records: NOAA GHCN-Daily, station USW00024145, 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 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.