McHenry County Weather in October
Average highs run from 69°F on October 1 to 55°F on October 31, and lows from 48°F to 36°F. Normal precipitation for the month is 3.20 in over about 9 wet days.
October day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
October at a glance
- Average high
- 62°F
- Average low
- 42°F
- Precipitation
- 3.20 in
- Snowfall
- 0.2 in
- Record high
- 90°FOct 1, 1971
- Record low
- 15°FOct 29, 1952
- Chance of a freeze
- 82%
- Daylight
- 11 h 44 min to 10 h 22 min
- Cloud cover
- 62%
- Humidity
- 77%
- Dew point
- 42°F
- Wind
- 10.7 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 |
|---|---|---|---|---|---|---|
| Oct 1 | 69°F | 48°F | 90°F 1971 | 28°F 1993 | 29% | 0% |
| Oct 2 | 69°F | 48°F | 88°F 1971 | 25°F 1974 | 29% | 0% |
| Oct 3 | 68°F | 47°F | 87°F 1971 | 20°F 1974 | 29% | 0% |
| Oct 4 | 68°F | 47°F | 85°F 1954 | 24°F 1974 | 29% | 0% |
| Oct 5 | 67°F | 47°F | 85°F 1967 | 25°F 1980 | 29% | 0% |
| Oct 6 | 67°F | 46°F | 88°F 1963 | 19°F 1952 | 29% | 0% |
| Oct 7 | 66°F | 46°F | 87°F 2007 | 23°F 2001 | 29% | 0% |
| Oct 8 | 66°F | 46°F | 85°F 2007 | 23°F 2001 | 29% | 0% |
| Oct 9 | 65°F | 45°F | 84°F 2007 | 27°F 1987 | 29% | 0% |
| Oct 10 | 65°F | 45°F | 87°F 2010 | 22°F 1964 | 29% | 0% |
| Oct 11 | 64°F | 45°F | 84°F 1962 | 22°F 1964 | 30% | 0% |
| Oct 12 | 64°F | 44°F | 85°F 1962 | 23°F 1967 | 30% | 0% |
| Oct 13 | 64°F | 44°F | 83°F 1995 | 26°F 1957 | 30% | 0% |
| Oct 14 | 63°F | 43°F | 88°F 1975 | 20°F 1979 | 30% | 1% |
| Oct 15 | 63°F | 43°F | 85°F 1962 | 22°F 1995 | 30% | 1% |
| Oct 16 | 62°F | 43°F | 85°F 1968 | 19°F 1995 | 30% | 1% |
| Oct 17 | 62°F | 42°F | 81°F 1968 | 26°F 1992 | 30% | 1% |
| Oct 18 | 61°F | 42°F | 82°F 1953 | 17°F 1952 | 30% | 1% |
| Oct 19 | 60°F | 41°F | 84°F 1953 | 19°F 1992 | 30% | 1% |
| Oct 20 | 60°F | 41°F | 82°F 1953 | 19°F 1992 | 30% | 1% |
| Oct 21 | 59°F | 41°F | 84°F 1953 | 16°F 1952 | 30% | 1% |
| Oct 22 | 59°F | 40°F | 84°F 1953 | 22°F 2018 | 30% | 1% |
| Oct 23 | 58°F | 40°F | 83°F 1953 | 19°F 1969 | 30% | 1% |
| Oct 24 | 58°F | 39°F | 84°F 1963 | 18°F 1981 | 30% | 1% |
| Oct 25 | 57°F | 39°F | 80°F 1963 | 19°F 1981 | 30% | 1% |
| Oct 26 | 57°F | 38°F | 76°F 1989 | 16°F 1962 | 30% | 1% |
| Oct 27 | 57°F | 38°F | 78°F 1964 | 19°F 1979 | 30% | 1% |
| Oct 28 | 56°F | 38°F | 75°F 1955 | 21°F 1969 | 29% | 2% |
| Oct 29 | 56°F | 37°F | 73°F 1974 | 15°F 1952 | 29% | 2% |
| Oct 30 | 55°F | 37°F | 79°F 2024 | 20°F 1988 | 29% | 2% |
| Oct 31 | 55°F | 36°F | 76°F 1971 | 20°F 2020 | 29% | 2% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CDT).
- October 1
- sunrise 6:51 AM, sunset 6:35 PM
- October 31
- sunrise 7:26 AM, sunset 5:48 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00112048 (Crystal Lake 4NW), public domain. Records: NOAA GHCN-Daily, station USC00471205, 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.