Frost dates for Conception, MO
At Conception, the median last spring frost (32°F) is Apr 17 and the median first fall frost is Oct 20, for a typical growing season of 184 days. For a 90% chance that the last frost has passed, wait until Apr 30. Nearby ZIP codes are in USDA hardiness zones 5b to 6a.
- Apr 17Last spring frost (median)50% chance of 32°F after this date
- Apr 30Safer planting date10% chance of 32°F after this date
- Oct 20First fall frost (median)50% chance of 32°F by this date
- 184 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 | Apr 14 | Apr 27 | May 7 |
| 32°F | Apr 3 | Apr 17 | Apr 30 |
| 28°F | Mar 25 | Apr 8 | Apr 22 |
| 24°F | Mar 14 | Apr 1 | Apr 14 |
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 | Sep 25 | Oct 10 | Oct 24 |
| 32°F | Oct 3 | Oct 20 | Nov 2 |
| 28°F | Oct 13 | Oct 30 | Nov 14 |
| 24°F | Oct 25 | Nov 7 | Nov 23 |
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 | 147 days | 165 days | 185 days |
| 32°F | 166 days | 184 days | 204 days |
| 28°F | 184 days | 203 days | 224 days |
| 24°F | 201 days | 221 days | 243 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 |
|---|---|---|---|
| 64433 | 6a | -10 to -5°F | 0 km |
| 64432 | 6a | -10 to -5°F | 3 km |
| 64434 | 6a | -10 to -5°F | 5 km |
| 64457 | 6a | -10 to -5°F | 9 km |
| 64479 | 5b | -15 to -10°F | 11 km |
| 64489 | 6a | -10 to -5°F | 11 km |
| 64423 | 6a | -10 to -5°F | 15 km |
| 64427 | 6a | -10 to -5°F | 20 km |
| 64480 | 6a | -10 to -5°F | 21 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 USC00231822, at 40.2394, -94.6833, elevation 338 m (1,108 ft).
- Data quality: Standard (24+ years of data), 29 years of freeze data.
- Average days per year at or below 32°F: 128.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Maryville 2e (17 km)
- Grant City 5wsw (30 km)
- Albany (30 km)
- Grant City (36 km)
- Cosby 2w (43 km)
- Amity 4 NE (47 km)
- Oregon (49 km)
- St. Joseph Rosecrans Airport (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.