Frost dates for Lafayette Purdue Univ Airport, IN
At Lafayette Purdue Univ Airport, the median last spring frost (32°F) is Apr 26 and the median first fall frost is Oct 18, for a typical growing season of 173 days. For a 90% chance that the last frost has passed, wait until May 14. Nearby ZIP codes are in USDA hardiness zone 6a.
- Apr 26Last spring frost (median)50% chance of 32°F after this date
- May 14Safer planting date10% chance of 32°F after this date
- Oct 18First 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 22 | May 7 | May 22 |
| 32°F | Apr 11 | Apr 26 | May 14 |
| 28°F | Mar 30 | Apr 13 | May 1 |
| 24°F | Mar 15 | Apr 1 | Apr 18 |
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 24 | Oct 7 | Oct 20 |
| 32°F | Oct 4 | Oct 18 | Oct 31 |
| 28°F | Oct 15 | Oct 28 | Nov 10 |
| 24°F | Oct 29 | Nov 8 | Nov 24 |
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 | 133 days | 152 days | 172 days |
| 32°F | 152 days | 173 days | 192 days |
| 28°F | 174 days | 196 days | 216 days |
| 24°F | 200 days | 221 days | 244 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 |
|---|---|---|---|
| 47907 | 6a | -10 to -5°F | 2 km |
| 47901 | 6a | -10 to -5°F | 4 km |
| 47904 | 6a | -10 to -5°F | 6 km |
| 47905 | 6a | -10 to -5°F | 15 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 USW00014835, at 40.4122, -86.9369, elevation 183 m (599 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 116.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- W Lafayette 6 NW (8 km)
- Lafayette 8 S (13 km)
- Attica 2e (26 km)
- Chalmers 5 W (28 km)
- Delphi 2 N (32 km)
- Frankfort Disposal (39 km)
- Boswell 4wnw (46 km)
- Crawfordsville 6 SE (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.