Frost dates for Fort Calhoun 4w, NE
At Fort Calhoun 4w, the median last spring frost (32°F) is Apr 19 and the median first fall frost is Oct 17, for a typical growing season of 180 days. For a 90% chance that the last frost has passed, wait until May 6. Nearby ZIP codes are in USDA hardiness zones 5b to 6a.
- Apr 19Last spring frost (median)50% chance of 32°F after this date
- May 6Safer planting date10% chance of 32°F after this date
- Oct 17First fall frost (median)50% chance of 32°F by this date
- 180 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 16 | May 1 | May 14 |
| 32°F | Apr 5 | Apr 19 | May 6 |
| 28°F | Mar 28 | Apr 9 | Apr 24 |
| 24°F | Mar 16 | 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 23 | Oct 7 | Oct 20 |
| 32°F | Oct 1 | Oct 17 | Oct 31 |
| 28°F | Oct 12 | Oct 27 | Nov 9 |
| 24°F | Oct 20 | Nov 4 | Nov 18 |
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 | 139 days | 158 days | 178 days |
| 32°F | 158 days | 180 days | 198 days |
| 28°F | 177 days | 199 days | 221 days |
| 24°F | 196 days | 217 days | 239 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 |
|---|---|---|---|
| 68023 | 5b | -15 to -10°F | 7 km |
| 68068 | 6a | -10 to -5°F | 11 km |
| 68007 | 6a | -10 to -5°F | 11 km |
| 68034 | 6a | -10 to -5°F | 11 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 USC00252980, at 41.4453, -96.0928, elevation 399 m (1,310 ft).
- Data quality: Representative (10+ years), 15 years of freeze data.
- Average days per year at or below 32°F: 140.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Omaha #1 (12 km)
- Blair (13 km)
- Omaha Eppley Airfield (22 km)
- Valley NWS (27 km)
- Fremont (31 km)
- Gretna 4ne (33 km)
- Tekamah Muni Airport (36 km)
- Tekamah (39 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.