Frost dates for Effingham 3sw, IL
At Effingham 3sw, the median last spring frost (32°F) is Apr 13 and the median first fall frost is Oct 24, for a typical growing season of 191 days. For a 90% chance that the last frost has passed, wait until Apr 29. Nearby ZIP codes are in USDA hardiness zone 6b.
- Apr 13Last spring frost (median)50% chance of 32°F after this date
- Apr 29Safer planting date10% chance of 32°F after this date
- Oct 24First fall frost (median)50% chance of 32°F by this date
- 191 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 10 | Apr 24 | May 11 |
| 32°F | Apr 1 | Apr 13 | Apr 29 |
| 28°F | Mar 17 | Apr 2 | Apr 17 |
| 24°F | Mar 4 | 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 29 | Oct 13 | Oct 25 |
| 32°F | Oct 9 | Oct 24 | Nov 5 |
| 28°F | Oct 20 | Nov 1 | Nov 19 |
| 24°F | Nov 1 | Nov 13 | Dec 2 |
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 | 148 days | 170 days | 190 days |
| 32°F | 170 days | 191 days | 211 days |
| 28°F | 194 days | 214 days | 235 days |
| 24°F | 214 days | 235 days | 263 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 |
|---|---|---|---|
| 62401 | 6b | -5 to 0°F | 5 km |
| 62461 | 6b | -5 to 0°F | 10 km |
| 62411 | 6b | -5 to 0°F | 11 km |
| 62473 | 6b | -5 to 0°F | 12 km |
| 62467 | 6b | -5 to 0°F | 16 km |
| 62443 | 6b | -5 to 0°F | 18 km |
| 62414 | 6b | -5 to 0°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 USC00112687, at 39.1181, -88.6244, elevation 190 m (625 ft).
- Data quality: Standard (24+ years of data), 27 years of freeze data.
- Average days per year at or below 32°F: 114.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Neoga 4nw (28 km)
- Brownstown 4 SW (34 km)
- Shelbyville Dam (35 km)
- Windsor (37 km)
- Newton (41 km)
- Ramsey (41 km)
- Vandalia (44 km)
- Flora 5 NW (46 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.