Cass County climate

Cass County Weather in September

NOAA 1991-2020 normals for Deep Portage, 7.3 km from Cass County

Average highs run from 74°F on September 1 to 62°F on September 30, and lows from 53°F to 43°F.

September day by day

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

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

September at a glance

Average high
68°F
Average low
48°F
Record high
101°FSep 8, 1931
Record low
16°FSep 21, 1934
Chance of a freeze
30%
Daylight
13 h 20 min to 11 h 44 min
Cloud cover
59%
Humidity
69%
Dew point
47°F
Wind
11.4 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 174°F53°F93°F 191331°F 19350%
Sep 274°F53°F95°F 198332°F 19460%
Sep 373°F53°F95°F 198332°F 19060%
Sep 473°F53°F93°F 202328°F 19180%
Sep 573°F52°F91°F 194732°F 19090%
Sep 672°F52°F92°F 197831°F 19300%
Sep 772°F52°F94°F 197632°F 19560%
Sep 871°F51°F101°F 193128°F 19560%
Sep 971°F51°F94°F 193127°F 19240%
Sep 1071°F50°F98°F 193125°F 19170%
Sep 1170°F50°F96°F 193129°F 19410%
Sep 1270°F50°F87°F 193127°F 19110%
Sep 1370°F49°F88°F 193927°F 19020%
Sep 1469°F49°F90°F 193924°F 1923
Sep 1569°F49°F90°F 189727°F 1964
Sep 1668°F48°F86°F 194825°F 1922
Sep 1768°F48°F89°F 190827°F 1959
Sep 1867°F47°F83°F 190821°F 1929
Sep 1967°F47°F89°F 190821°F 1929
Sep 2067°F47°F87°F 190824°F 1973
Sep 2166°F46°F88°F 189816°F 1934
Sep 2266°F46°F92°F 193619°F 1913
Sep 2365°F45°F86°F 193724°F 1913
Sep 2465°F45°F86°F 193527°F 1971
Sep 2564°F45°F85°F 192024°F 1947
Sep 2664°F44°F81°F 192019°F 1939
Sep 2764°F44°F89°F 195222°F 1903
Sep 2863°F43°F83°F 190521°F 1967
Sep 2963°F43°F90°F 189724°F 1899
Sep 3062°F43°F88°F 202520°F 1930

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Cass County, in percent, and of at least 0.1 inch of snowfall.00.21102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

September 1
sunrise 6:37 AM, sunset 7:57 PM
September 30
sunrise 7:15 AM, sunset 6:59 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00212050 (Deep Portage), public domain. Records: NOAA GHCN-Daily, station USC00214652, 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.