Frost dates for Algonac Wastewater Plant, MI
At Algonac Wastewater Plant, the median last spring frost (32°F) is May 3 and the median first fall frost is Oct 18, for a typical growing season of 167 days. For a 90% chance that the last frost has passed, wait until May 23. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- May 3Last spring frost (median)50% chance of 32°F after this date
- May 23Safer planting date10% chance of 32°F after this date
- Oct 18First fall frost (median)50% chance of 32°F by this date
- 167 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 30 | May 18 | Jun 5 |
| 32°F | Apr 20 | May 3 | May 23 |
| 28°F | Apr 8 | Apr 22 | May 8 |
| 24°F | Mar 29 | Apr 10 | 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 23 | Oct 6 | Oct 20 |
| 32°F | Oct 4 | Oct 18 | Nov 1 |
| 28°F | Oct 18 | Oct 31 | Nov 12 |
| 24°F | Nov 1 | Nov 11 | 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 | 115 days | 140 days | 163 days |
| 32°F | 141 days | 167 days | 185 days |
| 28°F | 170 days | 189 days | 206 days |
| 24°F | 196 days | 214 days | 233 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 |
|---|---|---|---|
| 48001 | 6b | -5 to 0°F | 4 km |
| 48028 | 6b | -5 to 0°F | 7 km |
| 48039 | 6b | -5 to 0°F | 9 km |
| 48023 | 6b | -5 to 0°F | 14 km |
| 48054 | 6a | -10 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 USC00200106, at 42.6158, -82.5436, elevation 177 m (580 ft).
- Data quality: Representative (10+ years), 11 years of freeze data.
- Average days per year at or below 32°F: 137.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Mount Clemens Ang Base (22 km)
- Richmond 4 NNW (36 km)
- Grosse Pointe Farms (37 km)
- Port Huron (41 km)
- Detroit City Airport (45 km)
- Pontiac Wastewater Plant (58 km)
- Dearborn #2 (60 km)
- Yale 1 NNW (62 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.