U.S. Frost Dates by Weather Station

NOAA station USC00126164 · Indiana

Frost Dates for New Castle, IN

NOAA weather station New Castle 3 SW (USC00126164), Indiana · elevation 991 ft (302 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 12only 1 spring in 10 still has a frost later
  • Typical last frostApril 2750% chance of a frost after it
  • Typical first fall frostOctober 1750% chance of a frost before it
  • Frost-free season173 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at New Castle, INSpring: a frost after April 11 in 9 years out of 10, after April 27 in half of the years, after May 12 in 1 year out of 10. Fall: the first frost comes before October 4 in 1 year out of 10, before October 17 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 173 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 27First frost ~Oct 17Frost season at New Castle, INSpring: a frost after April 11 in 9 years out of 10, after April 27 in half of the years, after May 12 in 1 year out of 10. Fall: the first frost comes before October 4 in 1 year out of 10, before October 17 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 173 days.JFMAMJJASONDLast frost ~Apr 27First frost ~Oct 17
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 12October 4
50% (typical)April 27October 17
90% (likely)April 11October 28
Frost-free season (32°F, 50% chance)
173 days
Hard frost (28°F), last in spring, 50% chance after
April 15
Hard frost (28°F), first in fall, 50% chance before
October 27

The last 15 years (2006–2020 normals)

Typical last frost April 27 (same as the 30-year normal), typical first fall frost October 19 (2 days later). Frost-free season 174 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 New Castle: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 12, 20% May 7, 30% May 3, 40% April 30, 50% April 27, 60% April 23, 70% April 19, 80% April 16, 90% April 11. Observed last spring frost in recent years: 2021 May 11, 2022 April 28, 2023 April 25, 2024 April 23, 2025 April 17, 2026 May 3.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 12Apr 27Apr 112021: May 112022: April 282023: April 252024: April 232025: April 172026: May 3Fall at New Castle: chance of a frost before this dateFall, chance of a frost before the date: 10% October 4, 20% October 9, 30% October 12, 40% October 14, 50% October 17, 60% October 19, 70% October 21, 80% October 25, 90% October 28. Observed first fall frost in recent years: 2021 October 27, 2022 October 4, 2023 October 23, 2024 October 16, 2025 October 24.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 4Oct 17Oct 282021: October 272022: October 42023: October 232024: October 162025: 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 11October 27
2022April 28October 4
2023April 25October 23
2024April 23October 16
2025April 17October 24
2026May 3season not over yet

What these dates mean

The 173 days between the 50% dates in New Castle, April 27 and October 17, define the window when light frosts are less likely to interrupt garden activities. The 50% dates themselves indicate the point at which there is an even chance of a light frost occurring later in spring or earlier in fall. For a cautious plan, tender crops are best set out after the spring cautious date of May 12, which carries a 10% chance of a later frost, and harvested before the fall cautious date of October 4, which carries a 10% chance that a frost has already arrived. A hard frost at 28 °F, marked by the median dates of April 15 and October 27, can damage plants that survive a light frost, making it a more critical concern 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 12" 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 New Castle, INNumbered nearest stations: 1 — Rushville, IN — 20 mi; 2 — Anderson, IN — 23 mi; 3 — Farmland, IN — 28 mi; 4 — Shelbyville, IN — 33 mi; 5 — Hartford City, IN — 38 mi.INOH25 mi · 40 km1. Rushville, IN — 20 mi12. Anderson, IN — 23 mi23. Farmland, IN — 28 mi34. Shelbyville, IN — 33 mi45. Hartford City, IN — 38 mi5
  1. Rushville, IN 20 mi (33 km)
  2. Anderson, IN 23 mi (37 km)
  3. Farmland, IN 28 mi (45 km)
  4. Shelbyville, IN 33 mi (53 km)
  5. Hartford City, IN 38 mi (61 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: 39.8942, -85.3953.