Markham Weather in September
Average highs run from 90°F on September 1 to 86°F on September 30, and lows from 72°F to 65°F. Normal precipitation for the month is 5.79 in over about 10 wet days.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 88°F
- Average low
- 69°F
- Precipitation
- 5.79 in
- Record high
- 109°FSep 4, 2000
- Record low
- 46°FSep 27, 1942
- Chance of a freeze
- 0%
- Days of 90°F or more
- 15.6
- Daylight
- 12 h 44 min to 11 h 54 min
- Cloud cover
- 46%
- Humidity
- 75%
- Dew point
- 70°F
- Wind
- 7.8 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.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Sep 1 | 90°F | 72°F | 103°F 1954 | 61°F 2018 | 32% | 0% |
| Sep 2 | 90°F | 71°F | 102°F 2000 | 63°F 1915 | 32% | 0% |
| Sep 3 | 90°F | 71°F | 103°F 2000 | 63°F 1915 | 32% | 0% |
| Sep 4 | 90°F | 71°F | 109°F 2000 | 58°F 1974 | 33% | 0% |
| Sep 5 | 90°F | 71°F | 108°F 2000 | 59°F 1952 | 33% | 0% |
| Sep 6 | 90°F | 71°F | 98°F 1912 | 60°F 1976 | 33% | 0% |
| Sep 7 | 90°F | 71°F | 100°F 2023 | 60°F 1976 | 33% | 0% |
| Sep 8 | 89°F | 70°F | 101°F 2023 | 60°F 1974 | 33% | 0% |
| Sep 9 | 89°F | 70°F | 103°F 2023 | 57°F 1983 | 33% | 0% |
| Sep 10 | 89°F | 70°F | 101°F 2023 | 61°F 2025 | 33% | 0% |
| Sep 11 | 89°F | 70°F | 99°F 1954 | 58°F 2018 | 33% | 0% |
| Sep 12 | 89°F | 70°F | 98°F 2023 | 56°F 1959 | 33% | 0% |
| Sep 13 | 89°F | 69°F | 99°F 2023 | 59°F 2018 | 33% | 0% |
| Sep 14 | 88°F | 69°F | 98°F 2011 | 56°F 1945 | 33% | 0% |
| Sep 15 | 88°F | 69°F | 96°F 1953 | 56°F 1945 | 33% | 0% |
| Sep 16 | 88°F | 69°F | 97°F 1954 | 57°F 1979 | 33% | 0% |
| Sep 17 | 88°F | 68°F | 99°F 1953 | 59°F 1961 | 33% | 0% |
| Sep 18 | 88°F | 68°F | 98°F 2004 | 52°F 1981 | 32% | 0% |
| Sep 19 | 88°F | 68°F | 98°F 2004 | 52°F 1981 | 32% | 0% |
| Sep 20 | 87°F | 68°F | 99°F 1999 | 57°F 1981 | 32% | 0% |
| Sep 21 | 87°F | 68°F | 100°F 1956 | 54°F 1983 | 32% | 0% |
| Sep 22 | 87°F | 67°F | 98°F 1944 | 51°F 1983 | 31% | 0% |
| Sep 23 | 87°F | 67°F | 97°F 2005 | 53°F 1995 | 31% | 0% |
| Sep 24 | 87°F | 67°F | 97°F 1950 | 50°F 1989 | 31% | 0% |
| Sep 25 | 87°F | 67°F | 100°F 2005 | 51°F 1991 | 30% | 0% |
| Sep 26 | 86°F | 66°F | 95°F 1980 | 53°F 1991 | 30% | 0% |
| Sep 27 | 86°F | 66°F | 95°F 2005 | 46°F 1942 | 29% | 0% |
| Sep 28 | 86°F | 66°F | 96°F 2005 | 46°F 1942 | 29% | 0% |
| Sep 29 | 86°F | 65°F | 98°F 2000 | 48°F 1967 | 29% | 0% |
| Sep 30 | 86°F | 65°F | 96°F 1998 | 47°F 1916 | 28% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CDT).
- September 1
- sunrise 7:02 AM, sunset 7:46 PM
- September 30
- sunrise 7:17 AM, sunset 7:11 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00410569 (Bay City Wtr Wks), public domain. Records: NOAA GHCN-Daily, station USC00410569, 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.