U.S. Frost Dates by Weather Station

NOAA station USC00234705 · Missouri

Frost Dates for Lamar, MO

NOAA weather station Lamar 7 N (USC00234705), Missouri · elevation 963 ft (294 m) · hardiness zone 7a*

  • Lower-risk planting dateafter April 28only 1 spring in 10 still has a frost later
  • Typical last frostApril 950% chance of a frost after it
  • Typical first fall frostOctober 2750% chance of a frost before it
  • Frost-free season199 daystypical year, 32°F
  • Hardiness zone7acalculated*

The year at a glance

Frost season at Lamar, MOSpring: a frost after March 26 in 9 years out of 10, after April 9 in half of the years, after April 28 in 1 year out of 10. Fall: the first frost comes before October 13 in 1 year out of 10, before October 27 in half of the years, before November 10 in 9 years out of 10. Typical frost-free season: 199 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 9First frost ~Oct 27Frost season at Lamar, MOSpring: a frost after March 26 in 9 years out of 10, after April 9 in half of the years, after April 28 in 1 year out of 10. Fall: the first frost comes before October 13 in 1 year out of 10, before October 27 in half of the years, before November 10 in 9 years out of 10. Typical frost-free season: 199 days.JFMAMJJASONDLast frost ~Apr 9First frost ~Oct 27
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)April 28October 13
50% (typical)April 9October 27
90% (likely)March 26November 10
Frost-free season (32°F, 50% chance)
199 days
Hard frost (28°F), last in spring, 50% chance after
March 31
Hard frost (28°F), first in fall, 50% chance before
November 5

The last 15 years (2006–2020 normals)

Typical last frost April 10 (1 day later than the 30-year normal), typical first fall frost October 27. Frost-free season 200 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 Lamar: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 28, 20% April 22, 30% April 17, 40% April 13, 50% April 9, 60% April 6, 70% April 3, 80% March 31, 90% March 26. Observed last spring frost in recent years: 2021 April 23, 2022 April 10, 2023 April 24, 2024 March 28, 2025 April 8, 2026 March 29.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 28Apr 9Mar 262021: April 232022: April 102023: April 242024: March 282025: April 82026: March 29Fall at Lamar: chance of a frost before this dateFall, chance of a frost before the date: 10% October 13, 20% October 18, 30% October 22, 40% October 25, 50% October 27, 60% October 30, 70% November 1, 80% November 4, 90% November 10. Observed first fall frost in recent years: 2021 November 13, 2022 October 18, 2023 October 30, 2024 October 16, 2025 November 2.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 13Oct 27Nov 102021: November 132022: October 182023: October 302024: October 162025: November 2
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 23November 13
2022April 10October 18
2023April 24October 30
2024March 28October 16
2025April 8November 2
2026March 29season not over yet

What these dates mean

Setting out tender crops on the early spring date of March 26 in Lamar carries a 90% chance of a frost later that season, making it a gamble for growers.

The 50% date for light frost in spring is April 9; there is a 50% chance of a frost later than this date. For the fall, the 50% date is October 27, indicating a 50% chance of a frost earlier than this date. A cautious plan uses the April 28 date, which has only a 10% chance of frost later, for planting tender crops, and relies on the October 13 date, which has a 10% chance of frost earlier, to finish harvesting tender crops.

Hard frost at 28 °F, represented by the March 31 and November 5 50% dates, can damage plants more severely than a light 32 °F frost.

How to read the probabilities

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

  • Spring: "10% after April 28" 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 Lamar, MONumbered nearest stations: 1 — Nevada, MO — 17 mi; 2 — Fort Scott, KS — 27 mi; 3 — near Stockton, MO — 29 mi; 4 — Girard, KS — 31 mi; 5 — Joplin, MO — 33 mi.MOKS25 mi · 40 km1. Nevada, MO — 17 mi12. Fort Scott, KS — 27 mi23. near Stockton, MO — 29 mi34. Girard, KS — 31 mi45. Joplin, MO — 33 mi5
  1. Nevada, MO 17 mi (28 km)
  2. Fort Scott, KS 27 mi (44 km)
  3. near Stockton, MO 29 mi (46 km)
  4. Girard, KS 31 mi (50 km)
  5. Joplin, MO 33 mi (54 km)

Sources

* Hardiness zone 7a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 37.5983, -94.2842.