Frost dates for Pontiac Wastewater Plant, MI
At Pontiac Wastewater Plant, the median last spring frost (32°F) is Apr 26 and the median first fall frost is Oct 22, for a typical growing season of 177 days. For a 90% chance that the last frost has passed, wait until May 12. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- Apr 26Last spring frost (median)50% chance of 32°F after this date
- May 12Safer planting date10% chance of 32°F after this date
- Oct 22First fall frost (median)50% chance of 32°F by this date
- 177 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 5 | May 22 |
| 32°F | Apr 15 | Apr 26 | May 12 |
| 28°F | Apr 3 | Apr 16 | Apr 30 |
| 24°F | Mar 22 | Apr 4 | 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 28 | Oct 10 | Oct 23 |
| 32°F | Oct 7 | Oct 22 | Nov 4 |
| 28°F | Oct 20 | Nov 4 | Nov 17 |
| 24°F | Nov 1 | Nov 14 | Dec 1 |
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 | 138 days | 157 days | 175 days |
| 32°F | 158 days | 177 days | 195 days |
| 28°F | 180 days | 200 days | 218 days |
| 24°F | 204 days | 223 days | 243 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 |
|---|---|---|---|
| 48342 | 6a | -10 to -5°F | 2 km |
| 48341 | 6a | -10 to -5°F | 3 km |
| 48340 | 6a | -10 to -5°F | 5 km |
| 48326 | 6a | -10 to -5°F | 6 km |
| 48304 | 6a | -10 to -5°F | 6 km |
| 48309 | 6a | -10 to -5°F | 6 km |
| 48320 | 6a | -10 to -5°F | 7 km |
| 48302 | 6a | -10 to -5°F | 8 km |
| 48098 | 6b | -5 to 0°F | 8 km |
| 48359 | 6a | -10 to -5°F | 9 km |
| 48084 | 6b | -5 to 0°F | 11 km |
| 48009 | 6b | -5 to 0°F | 11 km |
| 48307 | 6a | -10 to -5°F | 11 km |
| 48085 | 6b | -5 to 0°F | 12 km |
| 48360 | 6a | -10 to -5°F | 12 km |
| 48306 | 6a | -10 to -5°F | 13 km |
| 48017 | 6b | -5 to 0°F | 14 km |
| 48083 | 6b | -5 to 0°F | 15 km |
| 48073 | 6b | -5 to 0°F | 15 km |
| 48362 | 6a | -10 to -5°F | 16 km |
| 48363 | 6a | -10 to -5°F | 17 km |
| 48317 | 6a | -10 to -5°F | 17 km |
| 48314 | 6b | -5 to 0°F | 17 km |
| 48316 | 6a | -10 to -5°F | 17 km |
| 48310 | 6b | -5 to 0°F | 17 km |
| 48094 | 6a | -10 to -5°F | 20 km |
| 48370 | 6a | -10 to -5°F | 23 km |
| 48095 | 6a | -10 to -5°F | 23 km |
| 48367 | 6a | -10 to -5°F | 24 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 USC00206658, at 42.6389, -83.2556, elevation 271 m (890 ft).
- Data quality: Representative (10+ years), 15 years of freeze data.
- Average days per year at or below 32°F: 135.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Pontiac Oakland Co Intl Airport (14 km)
- White Lake 4e (19 km)
- Farmington (21 km)
- Detroit City Airport (33 km)
- Dearborn #2 (33 km)
- Dearborn (36 km)
- Milford Gm Proving Ground (36 km)
- Mount Clemens Ang Base (36 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.