Frost dates for Arlington, WA
At Arlington, the median last spring frost (32°F) is Apr 22 and the median first fall frost is Oct 19, for a typical growing season of 181 days. For a 90% chance that the last frost has passed, wait until May 6. Nearby ZIP codes are in USDA hardiness zone 8b.
- Apr 22Last spring frost (median)50% chance of 32°F after this date
- May 6Safer planting date10% chance of 32°F after this date
- Oct 19First fall frost (median)50% chance of 32°F by this date
- 181 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 28 | May 10 | May 24 |
| 32°F | Apr 4 | Apr 22 | May 6 |
| 28°F | Mar 3 | Mar 25 | Apr 15 |
| 24°F | Jan 19 | Feb 26 | Mar 17 |
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 17 | Oct 2 | Oct 17 |
| 32°F | Oct 3 | Oct 19 | Nov 4 |
| 28°F | Oct 19 | Nov 3 | Nov 23 |
| 24°F | Oct 31 | Nov 21 | Dec 16 |
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 | 145 days | 164 days |
| 32°F | 159 days | 181 days | 205 days |
| 28°F | 197 days | 224 days | 252 days |
| 24°F | 238 days | 269 days | 310 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 |
|---|---|---|---|
| 98223 | 8b | 15 to 20°F | 13 km |
| 98292 | 8b | 15 to 20°F | 13 km |
| 98274 | 8b | 15 to 20°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 USC00450257, at 48.2006, -122.1281, elevation 30 m (100 ft).
- Data quality: Estimated from nearby stations (2+ years), 5 years of freeze data.
- Average days per year at or below 32°F: 94.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Everett (26 km)
- Mount Vernon 3 WNW (33 km)
- Sedro-Woolley (34 km)
- Everett Snohomish Airport (34 km)
- Darrington Ranger Station (39 km)
- Monroe (41 km)
- Coupeville 1 S (42 km)
- Whidbey Island NAS (43 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.