U.S. Frost Dates by Weather Station

NOAA station USC00232850 · Missouri

Frost Dates for Festus, MO

NOAA weather station Festus (USC00232850), Missouri · elevation 600 ft (183 m) · hardiness zone 6b*

  • Lower-risk planting dateafter April 25only 1 spring in 10 still has a frost later
  • Typical last frostApril 950% chance of a frost after it
  • Typical first fall frostOctober 2650% chance of a frost before it
  • Frost-free season197 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season at Festus, MOSpring: a frost after March 25 in 9 years out of 10, after April 9 in half of the years, after April 25 in 1 year out of 10. Fall: the first frost comes before October 14 in 1 year out of 10, before October 26 in half of the years, before November 8 in 9 years out of 10. Typical frost-free season: 197 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 9First frost ~Oct 26Frost season at Festus, MOSpring: a frost after March 25 in 9 years out of 10, after April 9 in half of the years, after April 25 in 1 year out of 10. Fall: the first frost comes before October 14 in 1 year out of 10, before October 26 in half of the years, before November 8 in 9 years out of 10. Typical frost-free season: 197 days.JFMAMJJASONDLast frost ~Apr 9First 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.

Frost dates (32°F)

Probability of frost, based on 25 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 25October 14
50% (typical)April 9October 26
90% (likely)March 25November 8
Frost-free season (32°F, 50% chance)
197 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 7 (2 days earlier than the 30-year normal), typical first fall frost October 28 (2 days later). Frost-free season 202 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 Festus: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 25, 20% April 20, 30% April 16, 40% April 13, 50% April 9, 60% April 6, 70% April 3, 80% March 31, 90% March 25. Observed last spring frost in recent years: 2021 April 23, 2022 April 20, 2023 April 25.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 25Apr 9Mar 252021: April 232022: April 202023: April 25Fall at Festus: chance of a frost before this dateFall, chance of a frost before the date: 10% October 14, 20% October 19, 30% October 22, 40% October 24, 50% October 26, 60% October 29, 70% October 31, 80% November 3, 90% November 8. Observed first fall frost in recent years: 2021 November 3, 2022 October 18, 2023 October 31.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 14Oct 26Nov 82021: November 32022: October 182023: October 31
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 3
2022April 20October 18
2023April 25October 31
2024incomplete recordno data
2025no datano data
2026no dataseason not over yet

What these dates mean

October 14 marks the cautious fall date in Festus for finishing the harvest of tender crops; there is only a 10% chance that a light frost has arrived before that day.

In spring, the cautious date for setting out tender crops is April 25, when the probability of a light frost later in the season drops to 10%. The 50% dates—April 9 for spring and October 26 for fall—represent the median point where a light frost is equally likely to have occurred or not, giving gardeners a reference for timing decisions.

Hard frosts at 28 °F, recorded at a 50% chance on March 31 and November 5, can damage plants more severely than the 32 °F light frosts, so they merit separate attention.

How to read the probabilities

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

  • Spring: "10% after April 25" 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 14" 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 Festus, MONumbered nearest stations: 1 — Farmington, MO — 30 mi; 2 — St. Charles, MO — 32 mi; 3 — St. Louis (Spirit of St. Louis Airport), MO — 32 mi; 4 — near Weldon Spring, MO — 36 mi; 5 — near Belleville, IL — 36 mi.MOIL25 mi · 40 km1. Farmington, MO — 30 mi12. St. Charles, MO — 32 mi23. St. Louis (Spirit of St. Louis Airport), MO — 32 mi34. near Weldon Spring, MO — 36 mi45. near Belleville, IL — 36 mi5
  1. Farmington, MO 30 mi (49 km)
  2. St. Charles, MO 32 mi (52 km)
  3. St. Louis (Spirit of St. Louis Airport), MO 32 mi (52 km)
  4. near Weldon Spring, MO 36 mi (57 km)
  5. near Belleville, IL 36 mi (58 km)

Sources

* Hardiness zone 6b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 38.2325, -90.3981.