Frost dates for McMillin Rsvr, WA
At McMillin Rsvr, the median last spring frost (32°F) is Apr 11 and the median first fall frost is Oct 30, for a typical growing season of 202 days. For a 90% chance that the last frost has passed, wait until Apr 29. Nearby ZIP codes are in USDA hardiness zone 8b.
- Apr 11Last spring frost (median)50% chance of 32°F after this date
- Apr 29Safer planting date10% chance of 32°F after this date
- Oct 30First fall frost (median)50% chance of 32°F by this date
- 202 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 17 | May 1 | May 17 |
| 32°F | Mar 23 | Apr 11 | Apr 29 |
| 28°F | Feb 19 | Mar 16 | Apr 8 |
| 24°F | Dec 31 | Feb 19 | Mar 16 |
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 30 | Oct 12 | Oct 31 |
| 32°F | Oct 13 | Oct 30 | Nov 17 |
| 28°F | Oct 28 | Nov 14 | Dec 8 |
| 24°F | Nov 8 | Dec 1 | Jan 9 |
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 | 142 days | 163 days | 186 days |
| 32°F | 177 days | 202 days | 226 days |
| 28°F | 213 days | 244 days | 279 days |
| 24°F | 252 days | 291 days | 339 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 98% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 98374 | 8b | 15 to 20°F | 1 km |
| 98373 | 8b | 15 to 20°F | 5 km |
| 98375 | 8b | 15 to 20°F | 6 km |
| 98372 | 8b | 15 to 20°F | 8 km |
| 98391 | 8b | 15 to 20°F | 8 km |
| 98371 | 8b | 15 to 20°F | 9 km |
| 98390 | 8b | 15 to 20°F | 9 km |
| 98446 | 8b | 15 to 20°F | 9 km |
| 98445 | 8b | 15 to 20°F | 11 km |
| 98338 | 8b | 15 to 20°F | 11 km |
| 98360 | 8b | 15 to 20°F | 12 km |
| 98387 | 8b | 15 to 20°F | 13 km |
| 98580 | 8b | 15 to 20°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 USC00455224, at 47.1358, -122.2558, elevation 176 m (579 ft).
- Data quality: Representative (10+ years), 24 years of freeze data.
- Average days per year at or below 32°F: 60.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Tacoma #1 (17 km)
- Buckley 1 NE (19 km)
- Mud Mountain Dam (24 km)
- Tacoma Narrows Airport (28 km)
- Kent (31 km)
- Seattle Tacoma Intl Airport (35 km)
- Landsburg (35 km)
- Palmer 3 ESE (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.