U.S. Frost Dates by Weather Station

NOAA station USC00119241 · Illinois

Frost Dates for White Hall, IL

NOAA weather station White Hall 1 E (USC00119241), Illinois · elevation 580 ft (177 m) · hardiness zone 6a*

  • Lower-risk planting dateafter April 28only 1 spring in 10 still has a frost later
  • Typical last frostApril 1350% chance of a frost after it
  • Typical first fall frostOctober 2250% chance of a frost before it
  • Frost-free season190 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at White Hall, ILSpring: a frost after March 30 in 9 years out of 10, after April 13 in half of the years, after April 28 in 1 year out of 10. Fall: the first frost comes before October 9 in 1 year out of 10, before October 22 in half of the years, before November 2 in 9 years out of 10. Typical frost-free season: 190 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 13First frost ~Oct 22Frost season at White Hall, ILSpring: a frost after March 30 in 9 years out of 10, after April 13 in half of the years, after April 28 in 1 year out of 10. Fall: the first frost comes before October 9 in 1 year out of 10, before October 22 in half of the years, before November 2 in 9 years out of 10. Typical frost-free season: 190 days.JFMAMJJASONDLast frost ~Apr 13First frost ~Oct 22
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 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 28October 9
50% (typical)April 13October 22
90% (likely)March 30November 2
Frost-free season (32°F, 50% chance)
190 days
Hard frost (28°F), last in spring, 50% chance after
April 2
Hard frost (28°F), first in fall, 50% chance before
November 1

The last 15 years (2006–2020 normals)

Typical last frost April 14 (1 day later than the 30-year normal), typical first fall frost October 22. 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 White Hall: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 28, 20% April 23, 30% April 20, 40% April 16, 50% April 13, 60% April 10, 70% April 7, 80% April 3, 90% March 30. Observed last spring frost in recent years: 2021 April 23, 2022 April 20, 2023 April 24, 2024 March 29, 2025 April 9, 2026 March 29.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 28Apr 13Mar 302021: April 232022: April 202023: April 242024: March 292025: April 92026: March 29Fall at White Hall: chance of a frost before this dateFall, chance of a frost before the date: 10% October 9, 20% October 14, 30% October 17, 40% October 19, 50% October 22, 60% October 24, 70% October 27, 80% October 29, 90% November 2. Observed first fall frost in recent years: 2021 November 2, 2022 October 8, 2023 October 30, 2024 October 16, 2025 October 25.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 9Oct 22Nov 22021: November 22022: October 82023: October 302024: October 162025: October 25
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 2
2022April 20October 8
2023April 24October 30
2024March 29October 16
2025April 9October 25
2026March 29season not over yet

What these dates mean

Setting out tender crops on March 30 in White Hall is a gamble, because there is a 90% chance of a light frost later than that date. The 50% date in spring is April 13; at that point a frost is equally likely to occur later as not, which helps a gardener gauge the middle of the risk range. In fall the 50% date is October 22, marking the moment when a frost is just as likely to have arrived earlier as to stay away.

A cautious planting plan uses April 28 for spring tender crops, since only a 10% chance of a frost remains after that date. To finish harvesting tender crops safely, the cautious fall date is October 9, when a frost earlier than that date is only 10% likely. Hard frosts at 28 °F are more damaging than light frosts at 32 °F, so the median hard-frost dates—April 2 in spring and November 1 in fall—signal a higher threat level for vulnerable plants.

How to read the probabilities

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

  • Spring: "10% after April 28" 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 9" 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 White Hall, ILNumbered nearest stations: 1 — Jacksonville, IL — 22 mi; 2 — Jerseyville, IL — 23 mi; 3 — Elsberry, MO — 29 mi; 4 — near Springfield, IL — 46 mi; 5 — Saverton Lock and Dam 22, MO — 48 mi.MO25 mi · 40 km1. Jacksonville, IL — 22 mi12. Jerseyville, IL — 23 mi23. Elsberry, MO — 29 mi34. near Springfield, IL — 46 mi45. Saverton Lock and Dam 22, MO — 48 mi5
  1. Jacksonville, IL 22 mi (36 km)
  2. Jerseyville, IL 23 mi (38 km)
  3. Elsberry, MO 29 mi (47 km)
  4. near Springfield, IL 46 mi (75 km)
  5. Saverton Lock and Dam 22, MO 48 mi (78 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: 39.4408, -90.3789.