South Lyon climate

South Lyon Weather in September

NOAA 1991-2020 normals for Whitmore Lake 1NW, 11.1 km from South Lyon

Average highs run from 77°F on September 1 to 68°F on September 30, and lows from 55°F to 45°F. Normal precipitation for the month is 3.11 in.

September day by day

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

Normal daily high and low temperature at South Lyon, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
74°F
Average low
50°F
Precipitation
3.11 in
Record high
100°FSep 1, 1953
Record low
30°FSep 29, 1961
Chance of a freeze
13%
Days of 90°F or more
1.0
Daylight
13 h 09 min to 11 h 47 min
Cloud cover
53%
Humidity
73%
Dew point
53°F
Wind
9.2 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 177°F55°F100°F 195343°F 19670%
Sep 277°F55°F100°F 195343°F 19580%
Sep 377°F54°F98°F 195346°F 19650%
Sep 477°F54°F91°F 199947°F 19520%
Sep 577°F54°F100°F 195444°F 20000%
Sep 676°F54°F96°F 201641°F 19620%
Sep 776°F53°F96°F 201642°F 19620%
Sep 876°F53°F96°F 200242°F 19560%
Sep 976°F53°F94°F 200243°F 20170%
Sep 1076°F52°F95°F 201340°F 20170%
Sep 1175°F52°F96°F 195238°F 19670%
Sep 1275°F52°F97°F 195240°F 19670%
Sep 1375°F51°F96°F 195237°F 19640%
Sep 1474°F51°F93°F 202138°F 19630%
Sep 1574°F51°F89°F 201839°F 20070%
Sep 1674°F50°F92°F 195535°F 20070%
Sep 1774°F50°F95°F 195536°F 19590%
Sep 1873°F49°F93°F 195540°F 19660%
Sep 1973°F49°F93°F 195534°F 20200%
Sep 2072°F49°F88°F 201634°F 19560%
Sep 2172°F48°F97°F 201734°F 19560%
Sep 2272°F48°F94°F 201733°F 1999
Sep 2371°F48°F96°F 201734°F 1967
Sep 2471°F47°F94°F 201734°F 1950
Sep 2570°F47°F96°F 201737°F 1967
Sep 2670°F47°F96°F 201735°F 1966
Sep 2770°F46°F88°F 199931°F 1965
Sep 2869°F46°F87°F 195935°F 1964
Sep 2969°F46°F90°F 195330°F 1961
Sep 3068°F45°F82°F 200236°F 2005

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at South Lyon, 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 (EDT).

September 1
sunrise 7:00 AM, sunset 8:09 PM
September 30
sunrise 7:31 AM, sunset 7:18 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00208972 (Whitmore Lake 1NW), public domain. Records: NOAA GHCN-Daily, station USW00014853, 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.