Frost dates for Chalmette, LA
At Chalmette, the median last spring frost (32°F) is Feb 10 and the median first fall frost is Dec 17, for a typical growing season of 309 days. For a 90% chance that the last frost has passed, wait until Mar 8. Nearby ZIP codes are in USDA hardiness zone 9b.
- Feb 10Last spring frost (median)50% chance of 32°F after this date
- Mar 8Safer planting date10% chance of 32°F after this date
- Dec 17First fall frost (median)50% chance of 32°F by this date
- 309 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 30 | Feb 26 | Mar 17 |
| 32°F | Jan 12 | Feb 10 | Mar 8 |
| 28°F | Dec 31 | Jan 26 | Feb 21 |
| 24°F | Dec 28 | Jan 18 | Feb 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 | Nov 10 | Nov 29 | Dec 26 |
| 32°F | Nov 21 | Dec 17 | Jan 14 |
| 28°F | Dec 4 | Jan 2 | Jan 30 |
| 24°F | Dec 20 | Jan 9 | Feb 7 |
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 | 249 days | 277 days | 311 days |
| 32°F | 273 days | 309 days | 343 days |
| 28°F | 308 days | 340 days | 365 days |
| 24°F | 331 days | 365 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 98% |
| 28°F | 80% |
| 24°F | 42% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 70032 | 9b | 25 to 30°F | 1 km |
| 70043 | 9b | 25 to 30°F | 2 km |
| 70117 | 9b | 25 to 30°F | 5 km |
| 70131 | 9b | 25 to 30°F | 5 km |
| 70075 | 9b | 25 to 30°F | 7 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 USC00166130, at 29.9486, -89.9855, elevation 1 m (3 ft).
- Data quality: Estimated from nearby stations (2+ years), 3 years of freeze data.
- Average days per year at or below 32°F: 6.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Terrytown 3s (6 km)
- New Orleans Lakefront Airport (12 km)
- New Orleans Audubon (14 km)
- New Orleans Alvin Callender Fl (15 km)
- St. Bernard (17 km)
- Marrero 9 SSW (22 km)
- New Orleans Intl Airport (26 km)
- Slidell (41 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.