NOAA station USC00331592 · Ohio
Frost Dates for Circleville, OH
NOAA weather station Circleville (USC00331592), Ohio · elevation 675 ft (206 m) · hardiness zone 6b*
- Lower-risk planting dateafter May 4only 1 spring in 10 still has a frost later
- Typical last frostApril 1750% chance of a frost after it
- Typical first fall frostOctober 2850% chance of a frost before it
- Frost-free season192 daystypical year, 32°F
- Hardiness zone6bcalculated*
The year at a glance
Frost dates (32°F)
| Chance | Last frost in spring after | First frost in fall before |
|---|---|---|
| 10% (unlikely) | May 4 | October 14 |
| 50% (typical) | April 17 | October 28 |
| 90% (likely) | April 2 | November 9 |
- Frost-free season (32°F, 50% chance)
- 192 days
- Hard frost (28°F), last in spring, 50% chance after
- April 4
- Hard frost (28°F), first in fall, 50% chance before
- November 7
The last 15 years (2006–2020 normals)
Typical last frost April 17 (same as the 30-year normal), typical first fall frost October 30 (2 days later). Frost-free season 193 days.
A shorter, more recent NOAA period. The 30-year normals above remain the main reference: 15 years carry more year-to-year noise.
Add these dates to your calendar Yearly reminders for the typical last frost, the lower-risk planting date and the typical first fall frost (.ics).
How the chance of frost changes with the date
What actually happened in recent years
| Year | Last spring frost | First fall frost |
|---|---|---|
| 2021 | April 23 | November 3 |
| 2022 | April 22 | October 8 |
| 2023 | April 26 | October 23 |
| 2024 | April 22 | October 17 |
| 2025 | April 18 | October 25 |
| 2026 | April 8 | season not over yet |
What these dates mean
Setting out tender crops on April 2 in Circleville carries a 90% chance of a light frost later, so it is a gamble. The 50% date is April 17; at that point a light frost is equally likely to occur later as not. The 50% date for fall is October 28, marking an even chance of a frost earlier. The hard-frost median dates are April 4 in spring and November 7 in fall; a 28 °F frost can damage plants that survive a 32 °F light frost, making it more critical.
A cautious spring plan waits until May 4, when only a 10% chance of a later light frost remains. In fall, finishing tender crops by October 14 keeps the risk of an earlier frost to 10%.
How to read the probabilities
The dates are probabilities from 30 years of weather, not a forecast for this year.
- Spring: "10% after May 4" means that in about one spring out of ten a frost still happens after that date. The 90% date is the earliest: a frost after it happens in most years.
- Fall: "10% before October 14" means that in about one fall out of ten the first frost arrives before that date.
- 50% is the typical date: half of the years are earlier, half are later.
- A light frost (32°F) damages tender plants; a hard frost (28°F) also stops most hardy vegetables.
Nearby weather stations
- near Columbus, OH 27 mi (43 km)
- Waverly, OH 34 mi (56 km)
- Westerville, OH 36 mi (57 km)
- New Lexington, OH 40 mi (65 km)
- Hillsboro, OH 44 mi (70 km)
Sources
- NOAA NCEI U.S. Climate Normals 1991–2020, station USC00331592
- NOAA NCEI U.S. Climate Normals
- PRISM Group, Oregon State University — 2023 USDA Plant Hardiness Zone GIS datasets
- NOAA NCEI U.S. Climate Normals 2006–2020 (15-year normals), station USC00331592
- NOAA NCEI Global Historical Climatology Network – Daily (GHCN-Daily), observed daily minimum temperature, retrieved 2026-10-08
* Hardiness zone 6b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.
Station coordinates: 39.6103, -82.9556.