U.S. Frost Dates by Weather Station

NOAA station USC00123547 · Indiana

Frost Dates for Greensburg, IN

NOAA weather station Greensburg (USC00123547), Indiana · elevation 937 ft (286 m) · hardiness zone 6b*

  • Lower-risk planting dateafter May 2only 1 spring in 10 still has a frost later
  • Typical last frostApril 1550% chance of a frost after it
  • Typical first fall frostOctober 2650% chance of a frost before it
  • Frost-free season194 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season at Greensburg, INSpring: a frost after March 31 in 9 years out of 10, after April 15 in half of the years, after May 2 in 1 year out of 10. Fall: the first frost comes before October 12 in 1 year out of 10, before October 26 in half of the years, before November 7 in 9 years out of 10. Typical frost-free season: 194 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 15First frost ~Oct 26Frost season at Greensburg, INSpring: a frost after March 31 in 9 years out of 10, after April 15 in half of the years, after May 2 in 1 year out of 10. Fall: the first frost comes before October 12 in 1 year out of 10, before October 26 in half of the years, before November 7 in 9 years out of 10. Typical frost-free season: 194 days.JFMAMJJASONDLast frost ~Apr 15First frost ~Oct 26
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.

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 2October 12
50% (typical)April 15October 26
90% (likely)March 31November 7
Frost-free season (32°F, 50% chance)
194 days
Hard frost (28°F), last in spring, 50% chance after
April 2
Hard frost (28°F), first in fall, 50% chance before
November 5

The last 15 years (2006–2020 normals)

Typical last frost April 14 (1 day earlier than the 30-year normal), typical first fall frost October 27 (1 day later). Frost-free season 195 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 Greensburg: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 2, 20% April 26, 30% April 21, 40% April 18, 50% April 15, 60% April 10, 70% April 7, 80% April 4, 90% March 31.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 2Apr 15Mar 31Fall at Greensburg: chance of a frost before this dateFall, chance of a frost before the date: 10% October 12, 20% October 18, 30% October 21, 40% October 24, 50% October 26, 60% October 28, 70% October 30, 80% November 2, 90% November 7.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 12Oct 26Nov 7
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.

What these dates mean

The 194 days between the 50% dates in Greensburg mark the middle window in which a light frost (32 °F) has a 50 % chance of occurring later than April 15 and earlier than October 26. The 50% dates are not frost dates; they simply show the point of even odds for a light frost in spring and fall. The 50% hard-frost dates are April 2 in spring and November 5 in fall.

For a cautious plan, May 2 is the spring date with only a 10 % chance of a frost later, making it the conservative choice for setting out tender crops. October 12 is the fall date with only a 10 % chance of a frost earlier, the prudent time to finish harvesting tender crops. A hard frost at 28 °F matters more than a light frost at 32 °F because it can kill or seriously injure plants that would otherwise survive the milder temperature.

How to read the probabilities

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

  • Spring: "10% after May 2" 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 12" 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 Greensburg, INNumbered nearest stations: 1 — Rushville, IN — 18 mi; 2 — Shelbyville, IN — 20 mi; 3 — Columbus, IN — 26 mi; 4 — New Castle, IN — 38 mi; 5 — Fairfield, OH — 48 mi.INOHKY25 mi · 40 km1. Rushville, IN — 18 mi12. Shelbyville, IN — 20 mi23. Columbus, IN — 26 mi34. New Castle, IN — 38 mi45. Fairfield, OH — 48 mi5
  1. Rushville, IN 18 mi (29 km)
  2. Shelbyville, IN 20 mi (33 km)
  3. Columbus, IN 26 mi (42 km)
  4. New Castle, IN 38 mi (61 km)
  5. Fairfield, OH 48 mi (77 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: 39.3475, -85.4892.