U.S. Frost Dates by Weather Station

NOAA station USC00116011 · Illinois

Frost Dates for Nashville, IL

NOAA weather station Nashville 1 E (USC00116011), Illinois · elevation 513 ft (156 m) · hardiness zone 6b*

  • Lower-risk planting dateafter April 22only 1 spring in 10 still has a frost later
  • Typical last frostApril 750% chance of a frost after it
  • Typical first fall frostOctober 2650% chance of a frost before it
  • Frost-free season201 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season at Nashville, ILSpring: a frost after March 24 in 9 years out of 10, after April 7 in half of the years, after April 22 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 6 in 9 years out of 10. Typical frost-free season: 201 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 7First frost ~Oct 26Frost season at Nashville, ILSpring: a frost after March 24 in 9 years out of 10, after April 7 in half of the years, after April 22 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 6 in 9 years out of 10. Typical frost-free season: 201 days.JFMAMJJASONDLast frost ~Apr 7First 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 27 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 22October 14
50% (typical)April 7October 26
90% (likely)March 24November 6
Frost-free season (32°F, 50% chance)
201 days
Hard frost (28°F), last in spring, 50% chance after
March 30
Hard frost (28°F), first in fall, 50% chance before
November 4

The last 15 years (2006–2020 normals)

Typical last frost April 7 (same as the 30-year normal), typical first fall frost October 27 (1 day later). Frost-free season 201 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 Nashville: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 22, 20% April 18, 30% April 13, 40% April 10, 50% April 7, 60% April 5, 70% April 2, 80% March 30, 90% March 24.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 22Apr 7Mar 24Fall at Nashville: chance of a frost before this dateFall, chance of a frost before the date: 10% October 14, 20% October 18, 30% October 22, 40% October 24, 50% October 26, 60% October 28, 70% October 31, 80% November 2, 90% November 6.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 14Oct 26Nov 6
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

Setting out tender crops on March 24 in Nashville is a gamble, carrying a 90 % chance of a light frost occurring later in spring. By contrast, the cautious date for planting tender crops is April 22, when only a 10 % chance of a later frost remains. In the fall, counting on tender crops as late as November 6 risks a 90 % chance that a light frost has already arrived, while the prudent finish date is October 14, with just a 10 % chance of an earlier frost.

The 50 % date for light frost in spring is April 7, meaning there is an even chance of a frost later than this date, and the 50 % date in fall is October 26, meaning there is an even chance of a frost earlier than this date. The 50 % dates for hard frost are March 30 in spring and November 4 in fall; hard frost at 28 °F can damage plants that survive a light frost at 32 °F, so those dates matter more.

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 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 Nashville, ILNumbered nearest stations: 1 — near Carlyle, IL — 20 mi; 2 — Mount Vernon, IL — 27 mi; 3 — near Belleville, IL — 29 mi; 4 — Salem, IL — 30 mi; 5 — Carbondale, IL — 44 mi.MOKYIN25 mi · 40 km1. near Carlyle, IL — 20 mi12. Mount Vernon, IL — 27 mi23. near Belleville, IL — 29 mi34. Salem, IL — 30 mi45. Carbondale, IL — 44 mi5
  1. near Carlyle, IL 20 mi (31 km)
  2. Mount Vernon, IL 27 mi (44 km)
  3. near Belleville, IL 29 mi (47 km)
  4. Salem, IL 30 mi (49 km)
  5. Carbondale, IL 44 mi (70 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: 38.3419, -89.3592.