Frost dates for Riverhead Rsch Farm, NY
At Riverhead Rsch Farm, the median last spring frost (32°F) is Apr 6 and the median first fall frost is Nov 9, for a typical growing season of 215 days. For a 90% chance that the last frost has passed, wait until Apr 19. Nearby ZIP codes are in USDA hardiness zone 7a.
- Apr 6Last spring frost (median)50% chance of 32°F after this date
- Apr 19Safer planting date10% chance of 32°F after this date
- Nov 9First fall frost (median)50% chance of 32°F by this date
- 215 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 7 | Apr 20 | May 3 |
| 32°F | Mar 27 | Apr 6 | Apr 19 |
| 28°F | Mar 12 | Mar 28 | Apr 7 |
| 24°F | Feb 28 | Mar 15 | Mar 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 | Oct 15 | Oct 28 | Nov 10 |
| 32°F | Oct 28 | Nov 9 | Nov 22 |
| 28°F | Nov 7 | Nov 21 | Dec 5 |
| 24°F | Nov 18 | Dec 4 | Dec 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 | 170 days | 190 days | 207 days |
| 32°F | 198 days | 215 days | 233 days |
| 28°F | 220 days | 239 days | 259 days |
| 24°F | 243 days | 263 days | 286 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 |
|---|---|---|---|
| 11901 | 7a | 0 to 5°F | 7 km |
| 11931 | 7a | 0 to 5°F | 9 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 USC00307134, at 40.9625, -72.7161, elevation 30 m (100 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 86.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Baiting Hollow (4 km)
- Westhamptn Gabreski Airport (15 km)
- Upton COOP - Nwsfo New York (16 km)
- Mattituck (18 km)
- Shirley Brookhaven Airport (20 km)
- Mount Sinai (26 km)
- Setauket Strong (33 km)
- Bridgehampton (35 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.