Frost dates for Morgan City, LA
At Morgan City, the median last spring frost (32°F) is Jan 30 and the median first fall frost is Jan 1, for a typical growing season of 335 days. For a 90% chance that the last frost has passed, wait until Mar 5. Nearby ZIP codes are in USDA hardiness zone 9b.
- Jan 30Last spring frost (median)50% chance of 32°F after this date
- Mar 5Safer planting date10% chance of 32°F after this date
- Jan 1First fall frost (median)50% chance of 32°F by this date
- 335 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 | Jan 15 | Feb 15 | Mar 13 |
| 32°F | Dec 30 | Jan 30 | Mar 5 |
| 28°F | Dec 27 | Jan 22 | Mar 1 |
| 24°F | Dec 25 | Jan 16 | Feb 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 | Nov 20 | Dec 14 | Jan 14 |
| 32°F | Dec 2 | Jan 1 | Feb 2 |
| 28°F | Dec 17 | Jan 6 | Feb 5 |
| 24°F | Dec 23 | Jan 10 | Feb 2 |
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 | 268 days | 302 days | 337 days |
| 32°F | 297 days | 335 days | 365 days |
| 28°F | 328 days | 365 days | 365 days |
| 24°F | 352 days | 365 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 98% |
| 32°F | 80% |
| 28°F | 44% |
| 24°F | 19% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 70342 | 9b | 25 to 30°F | 6 km |
| 70340 | 9b | 25 to 30°F | 7 km |
| 70380 | 9b | 25 to 30°F | 10 km |
| 70392 | 9b | 25 to 30°F | 14 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 USC00166394, at 29.6833, -91.1761, elevation 2 m (5 ft).
- Data quality: Standard (24+ years of data), 30 years of freeze data.
- Average days per year at or below 32°F: 7.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Houma (35 km)
- Salt Point (36 km)
- Franklin 3 NW (39 km)
- Thibodaux 4 SE (40 km)
- Donaldsonville 4 SW (46 km)
- Carville 2 SW (57 km)
- Jeanerette 5 NW (60 km)
- Reserve (71 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.