Stanley County climate

Stanley County Weather in September

NOAA 1991-2020 normals for Ft Pierre 17 Wsw, 19.6 km from Stanley County

Average highs run from 85°F on September 1 to 72°F on September 30, and lows from 54°F to 43°F. Normal precipitation for the month is 1.50 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 Stanley County, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
79°F
Average low
49°F
Precipitation
1.50 in
Record high
108°FSep 2, 1983
Record low
21°FSep 22, 1995
Chance of a freeze
63%
Days of 90°F or more
6.5
Daylight
13 h 13 min to 11 h 45 min
Cloud cover
50%
Humidity
56%
Dew point
46°F
Wind
11.2 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 185°F54°F106°F 198340°F 196520%0%
Sep 284°F54°F108°F 198340°F 197420%0%
Sep 384°F54°F104°F 200536°F 197420%0%
Sep 484°F53°F105°F 195238°F 196220%0%
Sep 584°F53°F105°F 193338°F 196519%0%
Sep 683°F52°F107°F 197636°F 195619%0%
Sep 783°F52°F101°F 193335°F 198619%
Sep 883°F52°F102°F 195937°F 202019%
Sep 982°F51°F102°F 199435°F 194319%
Sep 1082°F51°F104°F 199832°F 202019%
Sep 1181°F51°F99°F 193533°F 195519%
Sep 1281°F50°F101°F 193934°F 197419%
Sep 1381°F50°F99°F 193931°F 194919%
Sep 1480°F49°F102°F 194831°F 194919%
Sep 1580°F49°F105°F 194832°F 201119%
Sep 1679°F49°F98°F 200035°F 195919%
Sep 1779°F48°F104°F 200034°F 198119%
Sep 1878°F48°F104°F 200030°F 199119%
Sep 1978°F47°F100°F 198424°F 199119%
Sep 2078°F47°F104°F 193733°F 198319%
Sep 2177°F47°F99°F 193731°F 199519%
Sep 2276°F46°F99°F 193621°F 199519%
Sep 2376°F46°F97°F 195829°F 194219%
Sep 2475°F45°F92°F 199025°F 200019%
Sep 2575°F45°F96°F 193829°F 194219%
Sep 2674°F44°F100°F 197424°F 196519%
Sep 2774°F44°F98°F 195226°F 195119%
Sep 2873°F44°F95°F 202121°F 195119%
Sep 2973°F43°F98°F 202429°F 198419%
Sep 3072°F43°F98°F 198023°F 197419%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Stanley County, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

September 1
sunrise 6:06 AM, sunset 7:19 PM
September 30
sunrise 6:40 AM, sunset 6:25 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00393076 (Ft Pierre 17 Wsw), public domain. Records: NOAA GHCN-Daily, station USW00024025, 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.