Frost dates for McLeansboro, IL
At McLeansboro, the median last spring frost (32°F) is Apr 11 and the median first fall frost is Oct 21, for a typical growing season of 190 days. For a 90% chance that the last frost has passed, wait until Apr 26. Nearby ZIP codes are in USDA hardiness zones 6b to 7a.
- Apr 11Last spring frost (median)50% chance of 32°F after this date
- Apr 26Safer planting date10% chance of 32°F after this date
- Oct 21First fall frost (median)50% chance of 32°F by this date
- 190 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 6 | Apr 22 | May 8 |
| 32°F | Mar 27 | Apr 11 | Apr 26 |
| 28°F | Mar 16 | Apr 1 | Apr 17 |
| 24°F | Mar 6 | Mar 22 | Apr 7 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 28 | Oct 11 | Oct 23 |
| 32°F | Oct 6 | Oct 21 | Nov 1 |
| 28°F | Oct 17 | Oct 30 | Nov 10 |
| 24°F | Oct 26 | Nov 7 | Nov 23 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 151 days | 170 days | 191 days |
| 32°F | 169 days | 190 days | 211 days |
| 28°F | 188 days | 209 days | 229 days |
| 24°F | 209 days | 230 days | 252 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 62859 | 6b | -5 to 0°F | 2 km |
| 62829 | 6b | -5 to 0°F | 10 km |
| 62828 | 6b | -5 to 0°F | 13 km |
| 62817 | 7a | 0 to 5°F | 16 km |
| 62887 | 7a | 0 to 5°F | 19 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00115515, at 38.0844, -88.5425, elevation 136 m (446 ft).
- Data quality: Representative (10+ years), 11 years of freeze data.
- Average days per year at or below 32°F: 110.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Carmi 3 (32 km)
- Benton 2 N (34 km)
- Fairfield Radio Wfiw (38 km)
- Harrisburg (38 km)
- Rend Lake Dam (39 km)
- Mount Vernon 3 NE (40 km)
- Grayville (52 km)
- Albion (54 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.