Frost dates for Sagemoor, WA
At Sagemoor, the median last spring frost (32°F) is Apr 30 and the median first fall frost is Oct 13, for a typical growing season of 166 days. For a 90% chance that the last frost has passed, wait until May 16. Nearby ZIP codes are in USDA hardiness zone 7a.
- Apr 30Last spring frost (median)50% chance of 32°F after this date
- May 16Safer planting date10% chance of 32°F after this date
- Oct 13First fall frost (median)50% chance of 32°F by this date
- 166 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 13 | May 28 |
| 32°F | Apr 15 | Apr 30 | May 16 |
| 28°F | Mar 24 | Apr 13 | May 1 |
| 24°F | Feb 24 | Mar 20 | 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 19 | Oct 1 | Oct 14 |
| 32°F | Sep 29 | Oct 13 | Oct 27 |
| 28°F | Oct 8 | Oct 23 | Nov 7 |
| 24°F | Oct 20 | Nov 2 | Nov 21 |
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 | 118 days | 140 days | 159 days |
| 32°F | 144 days | 166 days | 186 days |
| 28°F | 170 days | 193 days | 219 days |
| 24°F | 203 days | 230 days | 261 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 |
|---|---|---|---|
| 99301 | 7a | 0 to 5°F | 9 km |
| 99330 | 7a | 0 to 5°F | 11 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 USC00457247, at 46.3953, -119.0714, elevation 181 m (595 ft).
- Data quality: Representative (10+ years), 11 years of freeze data.
- Average days per year at or below 32°F: 127.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Eltopia 8 WSW (7 km)
- Pasco Tri Cities Airport (15 km)
- Richland (17 km)
- Kennewick (21 km)
- Ice Harbor Dam (22 km)
- Connell 1 W (33 km)
- Hatton 9 SE (48 km)
- McNary Dam (53 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.