Frost dates for Hatton 9 SE, WA
At Hatton 9 SE, the median last spring frost (32°F) is Apr 25 and the median first fall frost is Oct 15, for a typical growing season of 173 days. For a 90% chance that the last frost has passed, wait until May 11. Nearby ZIP codes are in USDA hardiness zone 7a.
- Apr 25Last spring frost (median)50% chance of 32°F after this date
- May 11Safer planting date10% chance of 32°F after this date
- Oct 15First fall frost (median)50% chance of 32°F by this date
- 173 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 26 | May 10 | May 27 |
| 32°F | Apr 4 | Apr 25 | May 11 |
| 28°F | Mar 7 | Apr 1 | Apr 25 |
| 24°F | Feb 10 | Mar 5 | Mar 30 |
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 22 | Oct 5 | Oct 18 |
| 32°F | Oct 2 | Oct 15 | Nov 1 |
| 28°F | Oct 10 | Oct 28 | Nov 16 |
| 24°F | Oct 22 | Nov 7 | Nov 28 |
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 | 124 days | 146 days | 167 days |
| 32°F | 151 days | 173 days | 199 days |
| 28°F | 180 days | 210 days | 238 days |
| 24°F | 217 days | 247 days | 279 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 |
|---|---|---|---|
| 99335 | 7a | 0 to 5°F | 18 km |
| 99371 | 7a | 0 to 5°F | 25 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 USC00453546, at 46.7225, -118.6525, elevation 459 m (1,505 ft).
- Data quality: Representative (10+ years), 24 years of freeze data.
- Average days per year at or below 32°F: 103.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Connell 1 W (19 km)
- Lind 3 NE (32 km)
- Sagemoor (48 km)
- Ritzville 1 SSE (49 km)
- Eltopia 8 WSW (53 km)
- Ice Harbor Dam (56 km)
- Lacrosse (60 km)
- Pasco Tri Cities Airport (62 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.