U.S. Frost Dates by Weather Station

NOAA station USC00237263 · Missouri

Frost Dates near Rolla, MO

NOAA weather station Rolla Missouri S&T (USC00237263), Missouri · elevation 1173 ft (358 m) · hardiness zone 6b*

Rolla is the nearest town to the station (0.4 mi away) in GeoNames (CC BY 4.0). The dates below are measured at the station, not in the town itself.

  • Lower-risk planting dateafter April 22only 1 spring in 10 still has a frost later
  • Typical last frostApril 550% chance of a frost after it
  • Typical first fall frostNovember 150% chance of a frost before it
  • Frost-free season207 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season near Rolla, MOSpring: a frost after March 21 in 9 years out of 10, after April 5 in half of the years, after April 22 in 1 year out of 10. Fall: the first frost comes before October 18 in 1 year out of 10, before November 1 in half of the years, before November 15 in 9 years out of 10. Typical frost-free season: 207 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 5First frost ~Nov 1Frost season near Rolla, MOSpring: a frost after March 21 in 9 years out of 10, after April 5 in half of the years, after April 22 in 1 year out of 10. Fall: the first frost comes before October 18 in 1 year out of 10, before November 1 in half of the years, before November 15 in 9 years out of 10. Typical frost-free season: 207 days.JFMAMJJASONDLast frost ~Apr 5First frost ~Nov 1
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 30 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 22October 18
50% (typical)April 5November 1
90% (likely)March 21November 15
Frost-free season (32°F, 50% chance)
207 days
Hard frost (28°F), last in spring, 50% chance after
March 26
Hard frost (28°F), first in fall, 50% chance before
November 10

The last 15 years (2006–2020 normals)

Typical last frost April 6 (1 day later than the 30-year normal), typical first fall frost October 31 (1 day earlier). Frost-free season 208 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 near Rolla: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 22, 20% April 16, 30% April 11, 40% April 8, 50% April 5, 60% April 2, 70% March 31, 80% March 26, 90% March 21. Observed last spring frost in recent years: 2021 April 22, 2022 April 19, 2023 March 29, 2024 March 28, 2025 April 8, 2026 March 18.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 22Apr 5Mar 212021: April 222022: April 192023: March 292024: March 282025: April 82026: March 18Fall near Rolla: chance of a frost before this dateFall, chance of a frost before the date: 10% October 18, 20% October 22, 30% October 26, 40% October 30, 50% November 1, 60% November 3, 70% November 5, 80% November 9, 90% November 15. Observed first fall frost in recent years: 2021 November 4, 2022 October 18, 2023 October 30, 2024 November 23, 2025 November 10.Fall: first frostChance of a frost before this date10%50%90%Nov 1Oct 18Nov 1Nov 152021: November 42022: October 182023: October 302024: November 232025: November 10
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 4
2022April 19October 18
2023March 29October 30
2024March 28November 23
2025April 8November 10
2026March 18season not over yet

What these dates mean

April 22 is the cautious spring light-frost date for the Rolla area; with only a 10 % chance of a frost later, a gardener can plan to set out tender crops at that time. The 50 % date of April 5 marks the point where the odds of a light frost later are even, while the March 21 date carries a 90 % chance and would be a gamble for tender seedlings.

October 18 serves as the cautious fall light-frost date, giving a gardener a 10 % chance that a frost has arrived earlier and thus a reliable point to finish harvesting tender crops. The 50 % date of November 1 indicates even odds for a frost earlier, and the November 15 date carries a 90 % chance, making it risky for late tender crops. The hard-frost 50 % dates are March 26 in spring and November 10 in fall; a hard frost at 28 °F can damage plant tissue that survives a 32 °F light 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 22" 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 18" 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 Rolla, MONumbered nearest stations: 1 — Vichy Rolla National Airport, MO — 12 mi; 2 — Salem, MO — 26 mi; 3 — Waynesville, MO — 27 mi; 4 — Licking, MO — 28 mi; 5 — Freedom, MO — 35 mi.25 mi · 40 km1. Vichy Rolla National Airport, MO — 12 mi12. Salem, MO — 26 mi23. Waynesville, MO — 27 mi34. Licking, MO — 28 mi45. Freedom, MO — 35 mi5
  1. Vichy Rolla National Airport, MO 12 mi (19 km)
  2. Salem, MO 26 mi (42 km)
  3. Waynesville, MO 27 mi (43 km)
  4. Licking, MO 28 mi (46 km)
  5. Freedom, MO 35 mi (56 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: 37.9567, -91.7761.