U.S. Frost Dates by Weather Station

NOAA station USC00124715 · Indiana

Frost Dates for Lafayette, IN

NOAA weather station Lafayette 8 S (USC00124715), Indiana · elevation 732 ft (223 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 6only 1 spring in 10 still has a frost later
  • Typical last frostApril 2050% chance of a frost after it
  • Typical first fall frostOctober 2050% chance of a frost before it
  • Frost-free season182 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Lafayette, INSpring: a frost after April 6 in 9 years out of 10, after April 20 in half of the years, after May 6 in 1 year out of 10. Fall: the first frost comes before October 4 in 1 year out of 10, before October 20 in half of the years, before November 2 in 9 years out of 10. Typical frost-free season: 182 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 20First frost ~Oct 20Frost season at Lafayette, INSpring: a frost after April 6 in 9 years out of 10, after April 20 in half of the years, after May 6 in 1 year out of 10. Fall: the first frost comes before October 4 in 1 year out of 10, before October 20 in half of the years, before November 2 in 9 years out of 10. Typical frost-free season: 182 days.JFMAMJJASONDLast frost ~Apr 20First 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.

Frost dates (32°F)

Probability of frost, based on 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 6October 4
50% (typical)April 20October 20
90% (likely)April 6November 2
Frost-free season (32°F, 50% chance)
182 days
Hard frost (28°F), last in spring, 50% chance after
April 7
Hard frost (28°F), first in fall, 50% chance before
October 31

The last 15 years (2006–2020 normals)

Typical last frost April 19 (1 day earlier than the 30-year normal), typical first fall frost October 23 (3 days later). Frost-free season 185 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 Lafayette: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 6, 20% May 1, 30% April 27, 40% April 23, 50% April 20, 60% April 17, 70% April 14, 80% April 11, 90% April 6. Observed last spring frost in recent years: 2021 May 8, 2022 April 27, 2023 April 25, 2024 April 25, 2025 April 13, 2026 April 21.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 6Apr 20Apr 62021: May 82022: April 272023: April 252024: April 252025: April 132026: April 21Fall at Lafayette: chance of a frost before this dateFall, chance of a frost before the date: 10% October 4, 20% October 10, 30% October 14, 40% October 17, 50% October 20, 60% October 22, 70% October 25, 80% October 28, 90% November 2. Observed first fall frost in recent years: 2021 November 1, 2022 October 8, 2023 October 31, 2024 October 17, 2025 October 24.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 4Oct 20Nov 22021: November 12022: October 82023: October 312024: October 172025: October 24
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 8November 1
2022April 27October 8
2023April 25October 31
2024April 25October 17
2025April 13October 24
2026April 21season not over yet

What these dates mean

May 6 is the cautious spring date for light frost; it gives gardeners a point at which there is only a 10 % chance of a frost later, allowing them to set out tender crops.

The 50% spring date is April 20; at that date the chance of a frost later is even, while the 50% fall date is October 20, when the chance of a frost earlier is even. For a cautious end of the season, October 4 is the fall date with only a 10 % chance that a frost has arrived, signaling when tender crops should be finished harvesting. The median hard-frost dates are April 7 in spring and October 31 in fall. A hard frost at 28 °F can injure plants that survive a light frost at 32 °F, so those dates are especially relevant for protecting sensitive crops.

How to read the probabilities

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

  • Spring: "10% after May 6" 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 4" 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 Lafayette, INNumbered nearest stations: 1 — Lafayette (Purdue University Airport), IN — 8 mi; 2 — West Lafayette, IN — 13 mi; 3 — near Frankfort, IN — 21 mi; 4 — Perrysville, IN — 35 mi; 5 — Whitestown, IN — 36 mi.INIL25 mi · 40 km1. Lafayette (Purdue University Airport), IN — 8 mi12. West Lafayette, IN — 13 mi23. near Frankfort, IN — 21 mi34. Perrysville, IN — 35 mi45. Whitestown, IN — 36 mi5
  1. Lafayette (Purdue University Airport), IN 8 mi (13 km)
  2. West Lafayette, IN 13 mi (21 km)
  3. near Frankfort, IN 21 mi (34 km)
  4. Perrysville, IN 35 mi (57 km)
  5. Whitestown, IN 36 mi (57 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: 40.2964, -86.9028.