Frost dates for Conroe Montgomery Co Airport, TX
At Conroe Montgomery Co Airport, the median last spring frost (32°F) is Mar 11 and the median first fall frost is Nov 19, for a typical growing season of 253 days. For a 90% chance that the last frost has passed, wait until Apr 3. Nearby ZIP codes are in USDA hardiness zone 9a.
- Mar 11Last spring frost (median)50% chance of 32°F after this date
- Apr 3Safer planting date10% chance of 32°F after this date
- Nov 19First fall frost (median)50% chance of 32°F by this date
- 253 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 24 | Apr 15 |
| 32°F | Feb 14 | Mar 11 | Apr 3 |
| 28°F | Jan 22 | Feb 21 | Mar 18 |
| 24°F | Dec 28 | Jan 30 | Mar 8 |
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 8 | Nov 26 |
| 32°F | Nov 1 | Nov 19 | Dec 9 |
| 28°F | Nov 11 | Dec 4 | Jan 8 |
| 24°F | Nov 30 | Jan 1 | Feb 3 |
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 | 202 days | 227 days | 254 days |
| 32°F | 224 days | 253 days | 286 days |
| 28°F | 253 days | 291 days | 333 days |
| 24°F | 289 days | 333 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 | 83% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 77303 | 9a | 20 to 25°F | 4 km |
| 77301 | 9a | 20 to 25°F | 6 km |
| 77306 | 9a | 20 to 25°F | 13 km |
| 77378 | 9a | 20 to 25°F | 14 km |
| 77302 | 9a | 20 to 25°F | 16 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 USW00053902, at 30.3567, -95.4139, elevation 75 m (245 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 27.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Conroe (7 km)
- Cleveland (32 km)
- Houston Hooks Mem Airport (35 km)
- Huntsville (41 km)
- Houston Intercont Airport (42 km)
- Huntsville Muni Airport (46 km)
- Livingston 2 NNE (63 km)
- Baytown (64 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.