U.S. Frost Dates by Weather Station

NOAA station USC00236357 · Missouri

Frost Dates for Oregon, MO

NOAA weather station Oregon (USC00236357), Missouri · elevation 1058 ft (323 m) · hardiness zone 6a*

  • Lower-risk planting dateafter April 30only 1 spring in 10 still has a frost later
  • Typical last frostApril 1650% chance of a frost after it
  • Typical first fall frostOctober 2050% chance of a frost before it
  • Frost-free season186 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Oregon, MOSpring: a frost after April 2 in 9 years out of 10, after April 16 in half of the years, after April 30 in 1 year out of 10. Fall: the first frost comes before October 3 in 1 year out of 10, before October 20 in half of the years, before November 1 in 9 years out of 10. Typical frost-free season: 186 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 16First frost ~Oct 20Frost season at Oregon, MOSpring: a frost after April 2 in 9 years out of 10, after April 16 in half of the years, after April 30 in 1 year out of 10. Fall: the first frost comes before October 3 in 1 year out of 10, before October 20 in half of the years, before November 1 in 9 years out of 10. Typical frost-free season: 186 days.JFMAMJJASONDLast frost ~Apr 16First frost ~Oct 20
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 26 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 30October 3
50% (typical)April 16October 20
90% (likely)April 2November 1
Frost-free season (32°F, 50% chance)
186 days
Hard frost (28°F), last in spring, 50% chance after
April 6
Hard frost (28°F), first in fall, 50% chance before
October 30

The last 15 years (2006–2020 normals)

Typical last frost April 15 (1 day earlier than the 30-year normal), typical first fall frost October 21 (1 day later). Frost-free season 189 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 Oregon: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 30, 20% April 25, 30% April 21, 40% April 18, 50% April 16, 60% April 12, 70% April 9, 80% April 6, 90% April 2.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 30Apr 16Apr 2Fall at Oregon: chance of a frost before this dateFall, chance of a frost before the date: 10% October 3, 20% October 10, 30% October 14, 40% October 17, 50% October 20, 60% October 22, 70% October 25, 80% October 28, 90% November 1.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 3Oct 20Nov 1
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.

What these dates mean

April 30 is the cautious spring date for Oregon, Missouri, and it gives a gardener a ten-percent chance of a light frost later, offering a dependable moment to set out tender crops.

The 50% light-frost dates are April 16 in spring and October 20 in fall; each marks the point at which a light frost is as likely as not to have occurred. A conservative fall plan uses the cautious date of October 3, when only ten percent of years experience a frost earlier, marking the latest point to finish harvesting tender crops.

Hard-frost 50% dates are April 6 and October 30; a hard frost at 28 °F can damage plants more severely than a light frost at 32 °F. The two 32°F 50% dates span 186 days, drawn from a 26-year record.

How to read the probabilities

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

  • Spring: "10% after April 30" 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 3" 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 Oregon, MONumbered nearest stations: 1 — Troy, KS — 11 mi; 2 — near Falls City, NE — 25 mi; 3 — Horton, KS — 29 mi; 4 — Maryville, MO — 30 mi; 5 — Conception, MO — 30 mi.MOKSNEIA25 mi · 40 km1. Troy, KS — 11 mi12. near Falls City, NE — 25 mi23. Horton, KS — 29 mi34. Maryville, MO — 30 mi45. Conception, MO — 30 mi5
  1. Troy, KS 11 mi (18 km)
  2. near Falls City, NE 25 mi (40 km)
  3. Horton, KS 29 mi (47 km)
  4. Maryville, MO 30 mi (48 km)
  5. Conception, MO 30 mi (49 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: 39.9808, -95.1464.