Frost dates for Harrisville 2nne, MI
At Harrisville 2nne, the median last spring frost (32°F) is May 8 and the median first fall frost is Oct 16, for a typical growing season of 160 days. For a 90% chance that the last frost has passed, wait until May 24. Nearby ZIP codes are in USDA hardiness zones 5b to 6a.
- May 8Last spring frost (median)50% chance of 32°F after this date
- May 24Safer planting date10% chance of 32°F after this date
- Oct 16First 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 | May 6 | May 21 | Jun 4 |
| 32°F | Apr 26 | May 8 | May 24 |
| 28°F | Apr 13 | Apr 27 | May 12 |
| 24°F | Apr 2 | Apr 14 | Apr 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 | Sep 23 | Oct 4 | Oct 17 |
| 32°F | Oct 2 | Oct 16 | Oct 30 |
| 28°F | Oct 15 | Oct 29 | Nov 12 |
| 24°F | Oct 29 | Nov 11 | Nov 25 |
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 | 116 days | 135 days | 155 days |
| 32°F | 140 days | 160 days | 178 days |
| 28°F | 163 days | 183 days | 204 days |
| 24°F | 191 days | 209 days | 228 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 |
|---|---|---|---|
| 48740 | 5b | -15 to -10°F | 7 km |
| 48721 | 6a | -10 to -5°F | 13 km |
| 48742 | 5b | -15 to -10°F | 14 km |
| 48738 | 6a | -10 to -5°F | 15 km |
| 48762 | 5b | -15 to -10°F | 22 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 USC00203628, at 44.6819, -83.2808, elevation 178 m (585 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 150.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Glennie 2se (37 km)
- Hale Loud Dam (43 km)
- Alpena Wastewater Plant (44 km)
- E Tawas (48 km)
- Alpena Co Regional Airport (49 km)
- Alpena 10nw (59 km)
- Hale 5ssw #2 (60 km)
- Lupton 1s (66 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.