Frost dates for Smithville, TX
At Smithville, the median last spring frost (32°F) is Mar 12 and the median first fall frost is Nov 19, for a typical growing season of 251 days. For a 90% chance that the last frost has passed, wait until Apr 11. Nearby ZIP codes are in USDA hardiness zone 9a.
- Mar 12Last spring frost (median)50% chance of 32°F after this date
- Apr 11Safer planting date10% chance of 32°F after this date
- Nov 19First fall frost (median)50% chance of 32°F by this date
- 251 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 | Mar 3 | Mar 30 | Apr 22 |
| 32°F | Feb 18 | Mar 12 | Apr 11 |
| 28°F | Jan 24 | Feb 26 | Mar 29 |
| 24°F | Dec 25 | Feb 1 | Mar 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 | Oct 24 | Nov 7 | Nov 29 |
| 32°F | Nov 1 | Nov 19 | Dec 11 |
| 28°F | Nov 11 | Dec 3 | Jan 3 |
| 24°F | Nov 27 | Dec 23 | 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 | 194 days | 225 days | 257 days |
| 32°F | 218 days | 251 days | 288 days |
| 28°F | 243 days | 285 days | 328 days |
| 24°F | 280 days | 328 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 87% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 78957 | 9a | 20 to 25°F | 2 km |
| 78949 | 9a | 20 to 25°F | 20 km |
| 78659 | 9a | 20 to 25°F | 22 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 USC00418415, at 30.0092, -97.1644, elevation 97 m (317 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 34.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- La Grange (30 km)
- Cedar Creek 5 S (30 km)
- Flatonia 4se (43 km)
- Elgin 1 N (44 km)
- Lexington (46 km)
- Austin Bergstrom Airport (53 km)
- Austin 6s (60 km)
- Luling (60 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.