Frost dates for Cairo 3n, IL
At Cairo 3n, the median last spring frost (32°F) is Apr 2 and the median first fall frost is Oct 31, for a typical growing season of 211 days. For a 90% chance that the last frost has passed, wait until Apr 17. Nearby ZIP codes are in USDA hardiness zones 7a to 7b.
- Apr 2Last spring frost (median)50% chance of 32°F after this date
- Apr 17Safer planting date10% chance of 32°F after this date
- Oct 31First fall frost (median)50% chance of 32°F by this date
- 211 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 12 | Apr 28 |
| 32°F | Mar 19 | Apr 2 | Apr 17 |
| 28°F | Mar 7 | Mar 24 | Apr 8 |
| 24°F | Feb 23 | Mar 13 | Mar 29 |
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 8 | Oct 20 | Nov 1 |
| 32°F | Oct 18 | Oct 31 | Nov 13 |
| 28°F | Oct 29 | Nov 10 | Nov 28 |
| 24°F | Nov 4 | Nov 21 | Dec 10 |
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 | 169 days | 190 days | 208 days |
| 32°F | 191 days | 211 days | 229 days |
| 28°F | 210 days | 230 days | 252 days |
| 24°F | 229 days | 252 days | 278 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 |
|---|---|---|---|
| 62914 | 7a | 0 to 5°F | 2 km |
| 62963 | 7a | 0 to 5°F | 6 km |
| 62964 | 7a | 0 to 5°F | 10 km |
| 42024 | 7a | 0 to 5°F | 13 km |
| 62962 | 7a | 0 to 5°F | 14 km |
| 63882 | 7b | 5 to 10°F | 14 km |
| 63834 | 7b | 5 to 10°F | 16 km |
| 62969 | 7a | 0 to 5°F | 17 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 USW00093809, at 37.0422, -89.1856, elevation 95 m (313 ft).
- Data quality: Representative (10+ years), 21 years of freeze data.
- Average days per year at or below 32°F: 81.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Grand Chain Dam 53 (22 km)
- Brookport Dam 52 (48 km)
- Anna 2 NNE (49 km)
- Dixon Springs Agric Center (64 km)
- Smithland L&d (68 km)
- Carbondale Sewage Plant (77 km)
- Carbondale Southern Il Airport (82 km)
- Rosiclare 5nw (84 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.