Frost dates for Saline Wastewater Plant, MI
At Saline Wastewater Plant, the median last spring frost (32°F) is May 2 and the median first fall frost is Oct 11, for a typical growing season of 160 days. For a 90% chance that the last frost has passed, wait until May 18. Nearby ZIP codes are in USDA hardiness zone 6a.
- May 2Last spring frost (median)50% chance of 32°F after this date
- May 18Safer planting date10% chance of 32°F after this date
- Oct 11First fall frost (median)50% chance of 32°F by this date
- 160 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 28 | May 13 | May 28 |
| 32°F | Apr 17 | May 2 | May 18 |
| 28°F | Apr 7 | Apr 21 | May 7 |
| 24°F | Mar 27 | Apr 8 | Apr 22 |
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 18 | Oct 1 | Oct 13 |
| 32°F | Sep 29 | Oct 11 | Oct 26 |
| 28°F | Oct 7 | Oct 24 | Nov 7 |
| 24°F | Oct 20 | Nov 4 | Nov 19 |
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 | 119 days | 138 days | 158 days |
| 32°F | 141 days | 160 days | 181 days |
| 28°F | 161 days | 184 days | 204 days |
| 24°F | 187 days | 209 days | 230 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 48176 | 6a | -10 to -5°F | 5 km |
| 48108 | 6a | -10 to -5°F | 8 km |
| 48160 | 6a | -10 to -5°F | 12 km |
| 48197 | 6a | -10 to -5°F | 12 km |
| 48103 | 6a | -10 to -5°F | 12 km |
| 48104 | 6a | -10 to -5°F | 12 km |
| 48190 | 6a | -10 to -5°F | 15 km |
| 48109 | 6a | -10 to -5°F | 16 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 USC00207308, at 42.1611, -83.7819, elevation 229 m (750 ft).
- Data quality: Representative (10+ years), 16 years of freeze data.
- Average days per year at or below 32°F: 153.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Saline 4sw (5 km)
- Ann Arbor Muni Airport (8 km)
- Ann Arbor SE (12 km)
- Milan Wastewater Plant (12 km)
- Milan 4 ESE (17 km)
- Ann Arbor U Of Mich (18 km)
- Manchester (20 km)
- Tecumseh (22 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.