Frost dates for Chicago Midway Airport 3sw, IL
At Chicago Midway Airport 3sw, the median last spring frost (32°F) is Apr 10 and the median first fall frost is Nov 1, for a typical growing season of 203 days. For a 90% chance that the last frost has passed, wait until Apr 26. Nearby ZIP codes are in USDA hardiness zone 6a.
- Apr 10Last spring frost (median)50% chance of 32°F after this date
- Apr 26Safer planting date10% chance of 32°F after this date
- Nov 1First fall frost (median)50% chance of 32°F by this date
- 203 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 9 | Apr 22 | May 6 |
| 32°F | Mar 30 | Apr 10 | Apr 26 |
| 28°F | Mar 15 | Apr 1 | Apr 14 |
| 24°F | Mar 4 | Mar 20 | Apr 3 |
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 10 | Oct 22 | Nov 3 |
| 32°F | Oct 21 | Nov 1 | Nov 16 |
| 28°F | Oct 30 | Nov 11 | Nov 26 |
| 24°F | Nov 7 | Nov 20 | Dec 6 |
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 | 181 days | 199 days |
| 32°F | 183 days | 203 days | 224 days |
| 28°F | 205 days | 225 days | 248 days |
| 24°F | 223 days | 246 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 |
|---|---|---|---|
| 60459 | 6a | -10 to -5°F | 1 km |
| 60455 | 6a | -10 to -5°F | 2 km |
| 60453 | 6a | -10 to -5°F | 3 km |
| 60415 | 6a | -10 to -5°F | 4 km |
| 60456 | 6a | -10 to -5°F | 4 km |
| 60458 | 6a | -10 to -5°F | 4 km |
| 60482 | 6a | -10 to -5°F | 6 km |
| 60805 | 6a | -10 to -5°F | 6 km |
| 60655 | 6a | -10 to -5°F | 8 km |
| 60803 | 6a | -10 to -5°F | 8 km |
| 60463 | 6a | -10 to -5°F | 8 km |
| 60643 | 6a | -10 to -5°F | 10 km |
| 60418 | 6a | -10 to -5°F | 11 km |
| 60472 | 6a | -10 to -5°F | 12 km |
| 60406 | 6a | -10 to -5°F | 12 km |
| 60445 | 6a | -10 to -5°F | 13 km |
| 60628 | 6a | -10 to -5°F | 14 km |
| 60469 | 6a | -10 to -5°F | 14 km |
| 60827 | 6a | -10 to -5°F | 15 km |
| 60633 | 6a | -10 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 USC00111577, at 41.7372, -87.7775, elevation 189 m (620 ft).
- Data quality: Standard (24+ years of data), 30 years of freeze data.
- Average days per year at or below 32°F: 108.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Chicago Midway Airport (6 km)
- Little Red School Hse (9 km)
- Chicago Northerly Island (19 km)
- Lisle-Morton Arboretum (26 km)
- Wheaton 3 SE (26 km)
- Park Forest (28 km)
- Romeoville WFO (30 km)
- Chicago Ohare Intl Airport (31 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.