Frost dates for Minonk, IL
At Minonk, the median last spring frost (32°F) is Apr 26 and the median first fall frost is Oct 17, for a typical growing season of 173 days. For a 90% chance that the last frost has passed, wait until May 10. Nearby ZIP codes are in USDA hardiness zone 5b.
- Apr 26Last spring frost (median)50% chance of 32°F after this date
- May 10Safer planting date10% chance of 32°F after this date
- Oct 17First fall frost (median)50% chance of 32°F by this date
- 173 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 21 | May 5 | May 20 |
| 32°F | Apr 11 | Apr 26 | May 10 |
| 28°F | Apr 1 | Apr 15 | May 1 |
| 24°F | Mar 18 | Apr 4 | Apr 21 |
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 23 | Oct 6 | Oct 20 |
| 32°F | Oct 1 | Oct 17 | Oct 29 |
| 28°F | Oct 14 | Oct 28 | Nov 9 |
| 24°F | Oct 25 | Nov 6 | Nov 21 |
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 | 134 days | 154 days | 174 days |
| 32°F | 152 days | 173 days | 193 days |
| 28°F | 174 days | 195 days | 213 days |
| 24°F | 195 days | 216 days | 236 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 |
|---|---|---|---|
| 61760 | 5b | -15 to -10°F | 3 km |
| 61358 | 5b | -15 to -10°F | 8 km |
| 61321 | 5b | -15 to -10°F | 8 km |
| 61516 | 5b | -15 to -10°F | 10 km |
| 61369 | 5b | -15 to -10°F | 13 km |
| 61740 | 5b | -15 to -10°F | 15 km |
| 61377 | 5b | -15 to -10°F | 17 km |
| 61738 | 5b | -15 to -10°F | 19 km |
| 61561 | 5b | -15 to -10°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 USC00115712, at 40.9125, -89.0339, elevation 229 m (750 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 135.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Streator 3 SE (27 km)
- Chenoa (33 km)
- Pontiac (34 km)
- Lacon (34 km)
- Congerville 2nw (37 km)
- Normal 4ne (41 km)
- Hennepin (46 km)
- Hennepin Wtr Trmt Plant (47 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.