Frost dates for St. Louis Sci Center, MO
At St. Louis Sci Center, the median last spring frost (32°F) is Apr 1 and the median first fall frost is Nov 4, for a typical growing season of 218 days. For a 90% chance that the last frost has passed, wait until Apr 18. Nearby ZIP codes are in USDA hardiness zone 7a.
- Apr 1Last spring frost (median)50% chance of 32°F after this date
- Apr 18Safer planting date10% chance of 32°F after this date
- Nov 4First fall frost (median)50% chance of 32°F by this date
- 218 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 27 | Apr 12 | Apr 27 |
| 32°F | Mar 14 | Apr 1 | Apr 18 |
| 28°F | Mar 5 | Mar 22 | Apr 7 |
| 24°F | Feb 22 | Mar 11 | Mar 29 |
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 15 | Oct 26 | Nov 7 |
| 32°F | Oct 24 | Nov 4 | Nov 21 |
| 28°F | Nov 2 | Nov 15 | Dec 4 |
| 24°F | Nov 9 | Nov 26 | Dec 15 |
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 | 178 days | 197 days | 216 days |
| 32°F | 198 days | 218 days | 240 days |
| 28°F | 217 days | 239 days | 264 days |
| 24°F | 237 days | 261 days | 284 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 63110 | 7a | 0 to 5°F | 1 km |
| 63108 | 7a | 0 to 5°F | 2 km |
| 63139 | 7a | 0 to 5°F | 3 km |
| 63112 | 7a | 0 to 5°F | 3 km |
| 63113 | 7a | 0 to 5°F | 4 km |
| 63103 | 7a | 0 to 5°F | 5 km |
| 63143 | 7a | 0 to 5°F | 5 km |
| 63117 | 7a | 0 to 5°F | 5 km |
| 63105 | 7a | 0 to 5°F | 5 km |
| 63109 | 7a | 0 to 5°F | 6 km |
| 63106 | 7a | 0 to 5°F | 6 km |
| 63116 | 7a | 0 to 5°F | 6 km |
| 63155 | 7a | 0 to 5°F | 6 km |
| 63130 | 7a | 0 to 5°F | 6 km |
| 63115 | 7a | 0 to 5°F | 6 km |
| 63107 | 7a | 0 to 5°F | 6 km |
| 63133 | 7a | 0 to 5°F | 7 km |
| 63120 | 7a | 0 to 5°F | 7 km |
| 63101 | 7a | 0 to 5°F | 7 km |
| 63144 | 7a | 0 to 5°F | 7 km |
| 63102 | 7a | 0 to 5°F | 7 km |
| 63119 | 7a | 0 to 5°F | 8 km |
| 63147 | 7a | 0 to 5°F | 9 km |
| 62059 | 7a | 0 to 5°F | 9 km |
| 63124 | 7a | 0 to 5°F | 9 km |
| 62090 | 7a | 0 to 5°F | 10 km |
| 63123 | 7a | 0 to 5°F | 11 km |
| 63126 | 7a | 0 to 5°F | 13 km |
| 63122 | 7a | 0 to 5°F | 14 km |
| 63127 | 7a | 0 to 5°F | 17 km |
| 63128 | 7a | 0 to 5°F | 18 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 USC00237452, at 38.6308, -90.2708, elevation 157 m (515 ft).
- Data quality: Representative (10+ years), 25 years of freeze data.
- Average days per year at or below 32°F: 79.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- St. Louis Lambert Intl Airport (16 km)
- St. Charles 7 SSW (23 km)
- St. Charles Elm Point (29 km)
- St. Peters 2 SE (32 km)
- St. Louis Sprt Of S L Airport (34 km)
- St. Charles Co Airport (36 km)
- Weldon Spring NWS (37 km)
- Festus (46 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.