Frost dates for Washington State Park, TX
At Washington State Park, the median last spring frost (32°F) is Mar 7 and the median first fall frost is Nov 19, for a typical growing season of 259 days. For a 90% chance that the last frost has passed, wait until Mar 31. Nearby ZIP codes are in USDA hardiness zone 9a.
- Mar 7Last spring frost (median)50% chance of 32°F after this date
- Mar 31Safer planting date10% chance of 32°F after this date
- Nov 19First fall frost (median)50% chance of 32°F by this date
- 259 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 | Feb 28 | Mar 22 | Apr 15 |
| 32°F | Feb 10 | Mar 7 | Mar 31 |
| 28°F | Jan 19 | Feb 19 | Mar 16 |
| 24°F | Dec 31 | Jan 31 | Mar 5 |
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 24 | Nov 7 | Nov 27 |
| 32°F | Nov 1 | Nov 19 | Dec 11 |
| 28°F | Nov 11 | Dec 3 | Jan 5 |
| 24°F | Nov 23 | Dec 28 | Feb 1 |
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 | 204 days | 233 days | 261 days |
| 32°F | 229 days | 259 days | 291 days |
| 28°F | 255 days | 291 days | 333 days |
| 24°F | 287 days | 330 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 99% |
| 24°F | 86% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 77880 | 9a | 20 to 25°F | 5 km |
| 77868 | 9a | 20 to 25°F | 12 km |
| 77830 | 9a | 20 to 25°F | 28 km |
| 77363 | 9a | 20 to 25°F | 30 km |
| 77875 | 9a | 20 to 25°F | 35 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 USC00419491, at 30.3236, -96.1594, elevation 66 m (215 ft).
- Data quality: Representative (10+ years), 26 years of freeze data.
- Average days per year at or below 32°F: 31.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Brenham (29 km)
- Bellville 6nne (33 km)
- College Station (35 km)
- Somerville Dam (37 km)
- Sealy (61 km)
- Houston Hooks Mem Airport (65 km)
- Conroe (65 km)
- Conroe Montgomery Co Airport (72 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.