U.S. Frost Dates by Weather Station

NOAA station USC00125407 · Indiana

Frost Dates for Martinsville, IN

NOAA weather station Martinsville 2 SW (USC00125407), Indiana · elevation 592 ft (180 m) · hardiness zone 6a*

  • 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 1550% chance of a frost before it
  • Frost-free season173 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Martinsville, INSpring: 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 2 in 1 year out of 10, before October 15 in half of the years, before October 29 in 9 years out of 10. Typical frost-free season: 173 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 24First frost ~Oct 15Frost season at Martinsville, INSpring: 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 2 in 1 year out of 10, before October 15 in half of the years, before October 29 in 9 years out of 10. Typical frost-free season: 173 days.JFMAMJJASONDLast frost ~Apr 24First frost ~Oct 15
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 30 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 11October 2
50% (typical)April 24October 15
90% (likely)April 10October 29
Frost-free season (32°F, 50% chance)
173 days
Hard frost (28°F), last in spring, 50% chance after
April 12
Hard frost (28°F), first in fall, 50% chance before
October 26

The last 15 years (2006–2020 normals)

Typical last frost April 23 (1 day earlier than the 30-year normal), typical first fall frost October 20 (5 days later). Frost-free season 177 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 Martinsville: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 11, 20% May 5, 30% May 1, 40% April 28, 50% April 24, 60% April 21, 70% April 17, 80% April 14, 90% April 10. Observed last spring frost in recent years: 2023 April 25, 2024 April 25, 2026 May 3.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 11Apr 24Apr 102023: April 252024: April 252026: May 3Fall at Martinsville: chance of a frost before this dateFall, chance of a frost before the date: 10% October 2, 20% October 7, 30% October 10, 40% October 13, 50% October 15, 60% October 18, 70% October 21, 80% October 24, 90% October 29. Observed first fall frost in recent years: 2023 October 23, 2025 October 23.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 2Oct 15Oct 292023: October 232025: 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
2021no dataincomplete record
2022incomplete recordincomplete record
2023April 25October 23
2024April 25incomplete record
2025incomplete recordOctober 23
2026May 3season not over yet

What these dates mean

The cautious fall date in Martinsville for finishing the harvest is October 2, when there is only a 10% chance that a light frost has arrived.

For a gardener, the cautious date in spring for setting out tender crops is May 11, while the 50% date, April 24, marks an even-odds point for a light frost. For a gardener, the cautious date in fall to finish harvesting tender crops is October 2, and the 50% date, October 15, marks an even-odds point for a light frost.

Hard frosts at 28°F, with median dates April 12 and October 26, can damage plants more severely than the 32°F light frosts because the lower temperature can freeze tissue that survives a light frost.

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 2" 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 Martinsville, INNumbered nearest stations: 1 — near Bloomington, IN — 16 mi; 2 — Spencer, IN — 19 mi; 3 — Indianapolis, IN — 23 mi; 4 — Columbus, IN — 33 mi; 5 — near Oolitic, IN — 36 mi.INILKYOH25 mi · 40 km1. near Bloomington, IN — 16 mi12. Spencer, IN — 19 mi23. Indianapolis, IN — 23 mi34. Columbus, IN — 33 mi45. near Oolitic, IN — 36 mi5
  1. near Bloomington, IN 16 mi (26 km)
  2. Spencer, IN 19 mi (30 km)
  3. Indianapolis, IN 23 mi (37 km)
  4. Columbus, IN 33 mi (53 km)
  5. near Oolitic, IN 36 mi (58 km)

Sources

* Hardiness zone 6a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 39.4039, -86.453.