Frost dates for Rend Lake Dam, IL
At Rend Lake Dam, the median last spring frost (32°F) is Apr 4 and the median first fall frost is Oct 27, for a typical growing season of 204 days. For a 90% chance that the last frost has passed, wait until Apr 19. Nearby ZIP codes are in USDA hardiness zones 6b to 7a.
- Apr 4Last spring frost (median)50% chance of 32°F after this date
- Apr 19Safer planting date10% chance of 32°F after this date
- Oct 27First fall frost (median)50% chance of 32°F by this date
- 204 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 | Mar 31 | Apr 15 | May 1 |
| 32°F | Mar 21 | Apr 4 | Apr 19 |
| 28°F | Mar 10 | Mar 26 | Apr 9 |
| 24°F | Feb 28 | Mar 15 | Mar 30 |
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 | Oct 5 | Oct 18 | Oct 28 |
| 32°F | Oct 16 | Oct 27 | Nov 8 |
| 28°F | Oct 25 | Nov 5 | Nov 23 |
| 24°F | Nov 2 | Nov 16 | Dec 4 |
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 | 163 days | 183 days | 202 days |
| 32°F | 185 days | 204 days | 222 days |
| 28°F | 203 days | 223 days | 246 days |
| 24°F | 223 days | 245 days | 269 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 |
|---|---|---|---|
| 62891 | 7a | 0 to 5°F | 5 km |
| 62884 | 6b | -5 to 0°F | 7 km |
| 62819 | 7a | 0 to 5°F | 7 km |
| 62825 | 7a | 0 to 5°F | 8 km |
| 62822 | 7a | 0 to 5°F | 9 km |
| 62874 | 7a | 0 to 5°F | 14 km |
| 62883 | 6b | -5 to 0°F | 17 km |
| 62894 | 6b | -5 to 0°F | 19 km |
| 62841 | 7a | 0 to 5°F | 20 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 USC00117187, at 38.0406, -88.9883, elevation 139 m (455 ft).
- Data quality: Estimated from nearby stations (2+ years), 8 years of freeze data.
- Average days per year at or below 32°F: 100.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Benton 2 N (6 km)
- Du Quoin 4 SE (19 km)
- Mount Vernon 3 NE (36 km)
- Carbondale Southern Il Airport (37 km)
- Carbondale Sewage Plant (38 km)
- McLeansboro (39 km)
- Nashville 1 E (47 km)
- Iuka 12 SW (50 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.