Chinook climate

Chinook Weather in September

NOAA 1991-2020 normals for Chinook, 0.4 km from Chinook

Average highs run from 78°F on September 1 to 66°F on September 30, and lows from 47°F to 36°F. Normal precipitation for the month is 0.99 in over about 7 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 Chinook, in °F, with the record for each date.020406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
72°F
Average low
41°F
Precipitation
0.99 in
Snowfall
0.4 in
Record high
104°FSep 7, 2022
Record low
18°FSep 21, 1995
Chance of a freeze
81%
Days of 90°F or more
2.0
Daylight
13 h 24 min to 11 h 43 min
Cloud cover
55%
Humidity
54%
Dew point
39°F
Wind
10.1 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 178°F47°F99°F 198335°F 199919%0%
Sep 278°F46°F101°F 199832°F 197419%0%
Sep 377°F46°F103°F 202229°F 196220%0%
Sep 477°F45°F98°F 197834°F 196220%0%
Sep 576°F45°F101°F 196735°F 196220%0%
Sep 676°F45°F98°F 198028°F 199220%0%
Sep 776°F44°F104°F 202233°F 196220%0%
Sep 875°F44°F97°F 197931°F 196220%0%
Sep 975°F44°F94°F 201726°F 196221%0%
Sep 1075°F43°F90°F 196330°F 198921%0%
Sep 1174°F43°F94°F 201723°F 198921%0%
Sep 1274°F43°F92°F 199027°F 197021%0%
Sep 1373°F42°F90°F 198724°F 197021%0%
Sep 1473°F42°F90°F 201222°F 197021%1%
Sep 1573°F41°F94°F 197926°F 198221%1%
Sep 1672°F41°F95°F 200929°F 198021%1%
Sep 1772°F41°F99°F 200927°F 199122%1%
Sep 1872°F40°F94°F 198123°F 199122%1%
Sep 1971°F40°F96°F 200924°F 199122%1%
Sep 2071°F40°F89°F 202524°F 199522%1%
Sep 2170°F39°F90°F 202518°F 199522%1%
Sep 2270°F39°F89°F 201125°F 199322%1%
Sep 2369°F39°F93°F 199221°F 200021%1%
Sep 2469°F38°F94°F 200920°F 198421%1%
Sep 2569°F38°F96°F 200126°F 198021%1%
Sep 2668°F37°F88°F 196324°F 196121%1%
Sep 2768°F37°F89°F 200119°F 198421%1%
Sep 2867°F37°F93°F 202218°F 198421%2%
Sep 2967°F36°F90°F 197621°F 198521%2%
Sep 3066°F36°F92°F 201119°F 198520%2%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Chinook, 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 6:34 AM, sunset 7:58 PM
September 30
sunrise 7:15 AM, sunset 6:58 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00241722 (Chinook), public domain. Records: NOAA GHCN-Daily, station USW00094012, 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.