U.S. Frost Dates by Weather Station

NOAA station USC00115079 · Illinois

Frost Dates for Lincoln, IL

NOAA weather station Lincoln (USC00115079), Illinois · elevation 583 ft (178 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 4only 1 spring in 10 still has a frost later
  • Typical last frostApril 2050% chance of a frost after it
  • Typical first fall frostOctober 1650% chance of a frost before it
  • Frost-free season179 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Lincoln, ILSpring: a frost after April 5 in 9 years out of 10, after April 20 in half of the years, after May 4 in 1 year out of 10. Fall: the first frost comes before October 3 in 1 year out of 10, before October 16 in half of the years, before October 29 in 9 years out of 10. Typical frost-free season: 179 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 20First frost ~Oct 16Frost season at Lincoln, ILSpring: a frost after April 5 in 9 years out of 10, after April 20 in half of the years, after May 4 in 1 year out of 10. Fall: the first frost comes before October 3 in 1 year out of 10, before October 16 in half of the years, before October 29 in 9 years out of 10. Typical frost-free season: 179 days.JFMAMJJASONDLast frost ~Apr 20First frost ~Oct 16
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 27 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 4October 3
50% (typical)April 20October 16
90% (likely)April 5October 29
Frost-free season (32°F, 50% chance)
179 days
Hard frost (28°F), last in spring, 50% chance after
April 7
Hard frost (28°F), first in fall, 50% chance before
October 26

The last 15 years (2006–2020 normals)

Typical last frost April 20 (same as the 30-year normal), typical first fall frost October 19 (3 days later). Frost-free season 179 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 Lincoln: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 4, 20% April 30, 30% April 25, 40% April 22, 50% April 20, 60% April 17, 70% April 13, 80% April 9, 90% April 5. Observed last spring frost in recent years: 2021 April 22, 2022 April 19, 2023 April 26, 2024 April 21, 2025 April 12, 2026 April 20.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 4Apr 20Apr 52021: April 222022: April 192023: April 262024: April 212025: April 122026: April 20Fall at Lincoln: chance of a frost before this dateFall, chance of a frost before the date: 10% October 3, 20% October 7, 30% October 11, 40% October 14, 50% October 16, 60% October 19, 70% October 21, 80% October 24, 90% October 29. Observed first fall frost in recent years: 2021 November 2, 2022 October 8, 2023 October 30, 2024 October 16, 2025 October 23.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 3Oct 16Oct 292021: November 22022: October 82023: October 302024: October 162025: October 23
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 2
2022April 19October 8
2023April 26October 30
2024April 21October 16
2025April 12October 23
2026April 20season not over yet

What these dates mean

October 3 is the cautious fall date for finishing the harvest of tender crops in Lincoln, Illinois; there is only a 10 % chance of a light frost occurring earlier.

For spring planting, the cautious date is May 4, when a light frost later than that date has a 10 % chance, while sowing on April 5 would involve a 90 % chance of frost and is a gamble. The 50 % dates—April 20 in spring and October 16 in fall—mark the point at which a light frost is equally likely to have happened or not, providing a neutral reference for gardeners. The hard-frost median dates are April 7 and October 26, and a temperature of 28 °F can damage plants that survive a 32 °F light frost, making hard frost a more critical threat. The data reflect 27 years of NOAA records for this station.

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 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 Lincoln, ILNumbered nearest stations: 1 — near Springfield, IL — 28 mi; 2 — Normal, IL — 34 mi; 3 — Peoria, IL — 40 mi; 4 — Chenoa, IL — 52 mi; 5 — Jacksonville, IL — 54 mi.25 mi · 40 km1. near Springfield, IL — 28 mi12. Normal, IL — 34 mi23. Peoria, IL — 40 mi34. Chenoa, IL — 52 mi45. Jacksonville, IL — 54 mi5
  1. near Springfield, IL 28 mi (45 km)
  2. Normal, IL 34 mi (55 km)
  3. Peoria, IL 40 mi (64 km)
  4. Chenoa, IL 52 mi (84 km)
  5. Jacksonville, IL 54 mi (87 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: 40.1519, -89.3386.