Frost dates for Slidell Airport, LA
At Slidell Airport, the median last spring frost (32°F) is Mar 3 and the median first fall frost is Nov 21, for a typical growing season of 263 days. For a 90% chance that the last frost has passed, wait until Mar 26. Nearby ZIP codes are in USDA hardiness zone 9a.
- Mar 3Last spring frost (median)50% chance of 32°F after this date
- Mar 26Safer planting date10% chance of 32°F after this date
- Nov 21First fall frost (median)50% chance of 32°F by this date
- 263 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 25 | Mar 20 | Apr 10 |
| 32°F | Feb 4 | Mar 3 | Mar 26 |
| 28°F | Jan 14 | Feb 14 | Mar 13 |
| 24°F | Dec 25 | Jan 27 | Mar 1 |
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 26 | Nov 8 | Nov 28 |
| 32°F | Nov 4 | Nov 21 | Dec 13 |
| 28°F | Nov 14 | Dec 6 | Jan 12 |
| 24°F | Nov 30 | Dec 30 | 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 | 207 days | 234 days | 264 days |
| 32°F | 236 days | 263 days | 296 days |
| 28°F | 263 days | 300 days | 336 days |
| 24°F | 298 days | 335 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 | 81% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 70460 | 9a | 20 to 25°F | 5 km |
| 70445 | 9a | 20 to 25°F | 7 km |
| 70452 | 9a | 20 to 25°F | 10 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 USW00053865, at 30.3433, -89.8222, elevation 8 m (27 ft).
- Data quality: Standard (24+ years of data), 27 years of freeze data.
- Average days per year at or below 32°F: 24.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Slidell (10 km)
- Covington 4 NNW (34 km)
- New Orleans Lakefront Airport (38 km)
- Chalmette (47 km)
- Bogalusa (49 km)
- Terrytown 3s (52 km)
- St. Bernard (52 km)
- New Orleans Audubon (56 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.