Frost dates for Oswego, NY
At Oswego, the median last spring frost (32°F) is Apr 22 and the median first fall frost is Oct 29, for a typical growing season of 187 days. For a 90% chance that the last frost has passed, wait until May 7. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- Apr 22Last spring frost (median)50% chance of 32°F after this date
- May 7Safer planting date10% chance of 32°F after this date
- Oct 29First fall frost (median)50% chance of 32°F by this date
- 187 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 23 | May 4 | May 19 |
| 32°F | Apr 9 | Apr 22 | May 7 |
| 28°F | Mar 31 | Apr 10 | Apr 22 |
| 24°F | Mar 17 | Mar 31 | Apr 11 |
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 29 | Oct 13 | Oct 30 |
| 32°F | Oct 9 | Oct 29 | Nov 11 |
| 28°F | Oct 29 | Nov 10 | Nov 26 |
| 24°F | Nov 7 | Nov 21 | Dec 7 |
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 | 141 days | 161 days | 181 days |
| 32°F | 165 days | 187 days | 207 days |
| 28°F | 194 days | 214 days | 232 days |
| 24°F | 216 days | 235 days | 256 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 |
|---|---|---|---|
| 13126 | 6a | -10 to -5°F | 7 km |
| 13115 | 6a | -10 to -5°F | 8 km |
| 13156 | 6b | -5 to 0°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 USC00306314, at 43.4500, -76.5369, elevation 99 m (324 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 119.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Fulton Oswego Co Airport (17 km)
- Fulton (20 km)
- Brewerton Lock 23 (36 km)
- Pulaski (36 km)
- Sodus 1w (50 km)
- Syracuse Hancock Intl Airport (51 km)
- Auburn (58 km)
- Camden (58 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.