U.S. Frost Dates by Weather Station

NOAA station USC00230143 · Missouri

Frost Dates for Amity, MO

NOAA weather station Amity 4 NE (USC00230143), Missouri · elevation 974 ft (297 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 4only 1 spring in 10 still has a frost later
  • Typical last frostApril 1950% chance of a frost after it
  • Typical first fall frostOctober 1950% chance of a frost before it
  • Frost-free season180 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Amity, MOSpring: a frost after April 4 in 9 years out of 10, after April 19 in half of the years, after May 4 in 1 year out of 10. Fall: the first frost comes before October 2 in 1 year out of 10, before October 19 in half of the years, before October 30 in 9 years out of 10. Typical frost-free season: 180 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 19First frost ~Oct 19Frost season at Amity, MOSpring: a frost after April 4 in 9 years out of 10, after April 19 in half of the years, after May 4 in 1 year out of 10. Fall: the first frost comes before October 2 in 1 year out of 10, before October 19 in half of the years, before October 30 in 9 years out of 10. Typical frost-free season: 180 days.JFMAMJJASONDLast frost ~Apr 19First frost ~Oct 19
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 4October 2
50% (typical)April 19October 19
90% (likely)April 4October 30
Frost-free season (32°F, 50% chance)
180 days
Hard frost (28°F), last in spring, 50% chance after
April 8
Hard frost (28°F), first in fall, 50% chance before
October 29

The last 15 years (2006–2020 normals)

Typical last frost April 20 (1 day later than the 30-year normal), typical first fall frost October 21 (2 days later). Frost-free season 183 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 Amity: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 4, 20% April 30, 30% April 27, 40% April 23, 50% April 19, 60% April 16, 70% April 13, 80% April 9, 90% April 4. Observed last spring frost in recent years: 2021 April 23.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 4Apr 19Apr 42021: April 23Fall at Amity: chance of a frost before this dateFall, chance of a frost before the date: 10% October 2, 20% October 9, 30% October 13, 40% October 16, 50% October 19, 60% October 21, 70% October 24, 80% October 27, 90% October 30. Observed first fall frost in recent years: 2021 October 22.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 2Oct 19Oct 302021: October 22
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 23October 22
2022no datano data
2023no datano data
2024no datano data
2025no datano data
2026no dataseason not over yet

What these dates mean

May 4 is the cautious spring date for light frost in Amity, and it marks the point after which a gardener can set out tender crops with only a 10 % chance of a later frost. Planting before April 4 would involve a 90 % chance of frost and is therefore a gamble.

The 50 % date is April 19; at that moment there is an even chance of a frost occurring later in the season. For the fall, October 2 is the cautious date, giving a 10 % chance that a frost has already arrived and allowing the final harvest of tender crops. The 50 % date is October 19, representing an even odds point for an earlier frost. The 50 % hard-frost dates are April 8 and October 29, and a hard frost at 28 °F can damage plant tissue that survives a light frost at 32 °F. The interval between the two 32 °F 50 % dates is 180 days, based on 29 years of record.

How to read the probabilities

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

  • Spring: "10% after May 4" 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 Amity, MONumbered nearest stations: 1 — Conception, MO — 30 mi; 2 — Bethany, MO — 31 mi; 3 — Troy, KS — 39 mi; 4 — Maryville, MO — 40 mi; 5 — Spickard, MO — 42 mi.MOIA25 mi · 40 km1. Conception, MO — 30 mi12. Bethany, MO — 31 mi23. Troy, KS — 39 mi34. Maryville, MO — 40 mi45. Spickard, MO — 42 mi5
  1. Conception, MO 30 mi (47 km)
  2. Bethany, MO 31 mi (50 km)
  3. Troy, KS 39 mi (63 km)
  4. Maryville, MO 40 mi (65 km)
  5. Spickard, MO 42 mi (68 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: 39.8914, -94.36.