Frost dates for Medford, WI
At Medford, the median last spring frost (32°F) is May 11 and the median first fall frost is Oct 1, for a typical growing season of 141 days. For a 90% chance that the last frost has passed, wait until May 26. Nearby ZIP codes are in USDA hardiness zones 4a to 4b.
- May 11Last spring frost (median)50% chance of 32°F after this date
- May 26Safer planting date10% chance of 32°F after this date
- Oct 1First fall frost (median)50% chance of 32°F by this date
- 141 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 | May 8 | May 23 | Jun 6 |
| 32°F | Apr 29 | May 11 | May 26 |
| 28°F | Apr 18 | May 1 | May 15 |
| 24°F | Apr 5 | Apr 20 | May 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 | Sep 7 | Sep 22 | Oct 4 |
| 32°F | Sep 17 | Oct 1 | Oct 13 |
| 28°F | Sep 27 | Oct 11 | Oct 25 |
| 24°F | Oct 8 | Oct 23 | Nov 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 | 102 days | 122 days | 140 days |
| 32°F | 124 days | 141 days | 159 days |
| 28°F | 141 days | 160 days | 180 days |
| 24°F | 164 days | 184 days | 203 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 |
|---|---|---|---|
| 54451 | 4a | -30 to -25°F | 9 km |
| 54480 | 4b | -25 to -20°F | 10 km |
| 54425 | 4b | -25 to -20°F | 14 km |
| 54405 | 4b | -25 to -20°F | 19 km |
| 54490 | 4a | -30 to -25°F | 22 km |
| 54470 | 4a | -30 to -25°F | 24 km |
| 54411 | 4b | -25 to -20°F | 26 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 USC00475255, at 45.1308, -90.3439, elevation 448 m (1,470 ft).
- Data quality: Standard (24+ years of data), 30 years of freeze data.
- Average days per year at or below 32°F: 177.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Owen 1e (26 km)
- Jump River 3e (40 km)
- Prentice #2 (46 km)
- Stanley Wastewater Plant (50 km)
- Merrill (54 km)
- Marshfield Muni Airport (56 km)
- Marshfield Exp. Farm (57 km)
- Wausau Dwtn Airport (61 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.