U.S. Frost Dates by Weather Station

NOAA station USW00093819 · Indiana

Frost Dates for Indianapolis, IN

NOAA weather station Indianapolis (USW00093819), Indiana · elevation 790 ft (241 m) · hardiness zone 6a*

  • 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 season193 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Indianapolis, INSpring: a frost after April 2 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 13 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: 193 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 15First frost ~Oct 26Frost season at Indianapolis, INSpring: a frost after April 2 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 13 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: 193 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.Today

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 2October 13
50% (typical)April 15October 26
90% (likely)April 2November 7
Frost-free season (32°F, 50% chance)
193 days
Hard frost (28°F), last in spring, 50% chance after
April 4
Hard frost (28°F), first in fall, 50% chance before
November 5

The last 15 years (2006–2020 normals)

Typical last frost April 15 (same as the 30-year normal), typical first fall frost October 28 (2 days 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 Indianapolis: 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 12, 70% April 9, 80% April 6, 90% April 2. Observed last spring frost in recent years: 2021 April 22, 2022 April 19, 2023 April 24, 2024 April 6, 2025 April 9, 2026 March 28.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 2Apr 15Apr 22021: April 222022: April 192023: April 242024: April 62025: April 92026: March 28Fall at Indianapolis: chance of a frost before this dateFall, chance of a frost before the date: 10% October 13, 20% October 18, 30% October 21, 40% October 24, 50% October 26, 60% October 28, 70% October 30, 80% November 2, 90% November 7. Observed first fall frost in recent years: 2021 November 3, 2022 October 19, 2023 October 30, 2024 November 21, 2025 October 24.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 13Oct 26Nov 72021: November 32022: October 192023: October 302024: November 212025: 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
2021April 22November 3
2022April 19October 19
2023April 24October 30
2024April 6November 21
2025April 9October 24
2026March 28season not over yet

What these dates mean

May 2, the cautious spring date, gives a gardener only a 10 % chance that a light frost will occur later, making it the date to set out tender crops with minimal risk. In the autumn, October 13 serves as the cautious fall date, providing a 10 % chance that a light frost has already arrived, so it marks the latest sensible time to finish harvesting tender crops.

The 50 % date is April 15 in spring; at that point there is an even chance of a frost later, while the 50 % date is October 26 in fall, when there is an even chance of a frost earlier. Hard frosts at 28°F, such as the median dates of April 4 and November 5, can damage plants that would survive a 32°F light frost, so they are a more critical threshold for growers.

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 13" 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 Indianapolis, INNumbered nearest stations: 1 — Whitestown, IN — 20 mi; 2 — Martinsville, IN — 23 mi; 3 — Shelbyville, IN — 29 mi; 4 — Tipton, IN — 37 mi; 5 — near Bloomington, IN — 39 mi.OHILKY25 mi · 40 km1. Whitestown, IN — 20 mi12. Martinsville, IN — 23 mi23. Shelbyville, IN — 29 mi34. Tipton, IN — 37 mi45. near Bloomington, IN — 39 mi5
  1. Whitestown, IN 20 mi (33 km)
  2. Martinsville, IN 23 mi (37 km)
  3. Shelbyville, IN 29 mi (46 km)
  4. Tipton, IN 37 mi (59 km)
  5. near Bloomington, IN 39 mi (63 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: 39.7075, -86.2803.