U.S. Frost Dates by Weather Station

NOAA station USC00333758 · Ohio

Frost Dates for Hillsboro, OH

NOAA weather station Hillsboro (USC00333758), Ohio · elevation 953 ft (291 m) · hardiness zone 6b*

  • Lower-risk planting dateafter May 11only 1 spring in 10 still has a frost later
  • Typical last frostApril 2450% chance of a frost after it
  • Typical first fall frostOctober 2050% chance of a frost before it
  • Frost-free season178 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season at Hillsboro, OHSpring: a frost after April 10 in 9 years out of 10, after April 24 in half of the years, after May 11 in 1 year out of 10. Fall: the first frost comes before October 6 in 1 year out of 10, before October 20 in half of the years, before November 1 in 9 years out of 10. Typical frost-free season: 178 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 24First frost ~Oct 20Frost season at Hillsboro, OHSpring: a frost after April 10 in 9 years out of 10, after April 24 in half of the years, after May 11 in 1 year out of 10. Fall: the first frost comes before October 6 in 1 year out of 10, before October 20 in half of the years, before November 1 in 9 years out of 10. Typical frost-free season: 178 days.JFMAMJJASONDLast frost ~Apr 24First frost ~Oct 20
frost likely chance fading 90% → 10% frost-free in a typical yearThe year at a glance. Blue: frost is likely; the gradient fades as the chance drops from 90% to 10%; green: the frost-free part of a typical year.Today

Frost dates (32°F)

Probability of frost, based on 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 11October 6
50% (typical)April 24October 20
90% (likely)April 10November 1
Frost-free season (32°F, 50% chance)
178 days
Hard frost (28°F), last in spring, 50% chance after
April 12
Hard frost (28°F), first in fall, 50% chance before
November 1

The last 15 years (2006–2020 normals)

Typical last frost April 26 (2 days later than the 30-year normal), typical first fall frost October 21 (1 day later). Frost-free season 176 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

Spring at Hillsboro: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 11, 20% May 5, 30% April 30, 40% April 27, 50% April 24, 60% April 21, 70% April 18, 80% April 15, 90% April 10. Observed last spring frost in recent years: 2021 May 3, 2022 April 27, 2023 April 26, 2024 April 23, 2025 April 18, 2026 May 4.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 11Apr 24Apr 102021: May 32022: April 272023: April 262024: April 232025: April 182026: May 4Fall at Hillsboro: chance of a frost before this dateFall, chance of a frost before the date: 10% October 6, 20% October 12, 30% October 15, 40% October 18, 50% October 20, 60% October 22, 70% October 25, 80% October 27, 90% November 1. Observed first fall frost in recent years: 2021 October 27, 2022 October 8, 2023 October 11, 2024 October 17, 2025 October 23.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 6Oct 20Nov 12021: October 272022: October 82023: October 112024: October 172025: October 23
Two charts, because spring and fall answer different questions: in spring, the chance that a frost still comes after a date; in fall, the chance that the first frost has already come before it. NOAA publishes these odds from 10% to 90%, so the lines stop there. ◆ marks the actual date in each recent year.

What actually happened in recent years

Observed dates of the last spring and first fall frost (32°F) at this station; ◆ marks them on the charts above
YearLast spring frostFirst fall frost
2021May 3October 27
2022April 27October 8
2023April 26October 11
2024April 23October 17
2025April 18October 23
2026May 4season not over yet

What these dates mean

Setting tender crops on the early spring date of April 10 carries a 90% chance of a frost later than that date, making it a gamble for growers in Hillsboro. The cautious alternative is the May 11 date, which has only a 10% chance of a later frost and therefore is the recommended day to set out tender crops in spring.

The 50% dates—April 24 in spring and October 20 in fall—represent the median odds for a frost occurrence. For a cautious autumn plan, the October 6 date is used, as it carries just a 10% chance of an earlier frost. A hard frost at 28 °F, noted on April 12 in spring and November 1 in fall, can injure plants more severely than a light frost at 32 °F.

How to read the probabilities

The dates are probabilities from 30 years of weather, not a forecast for this year.

  • Spring: "10% after May 11" 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 6" 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

Map of weather stations near Hillsboro, OHNumbered nearest stations: 1 — Xenia, OH — 30 mi; 2 — Waverly, OH — 35 mi; 3 — Circleville, OH — 44 mi; 4 — Franklin, OH — 44 mi; 5 — near Cincinnati, OH — 44 mi.OHKY25 mi · 40 km1. Xenia, OH — 30 mi12. Waverly, OH — 35 mi23. Circleville, OH — 44 mi34. Franklin, OH — 44 mi45. near Cincinnati, OH — 44 mi5
  1. Xenia, OH 30 mi (49 km)
  2. Waverly, OH 35 mi (56 km)
  3. Circleville, OH 44 mi (70 km)
  4. Franklin, OH 44 mi (71 km)
  5. near Cincinnati, OH 44 mi (71 km)

Sources

* 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: 39.2333, -83.6092.