U.S. Frost Dates by Weather Station

NOAA station USC00130112 · Iowa

Frost Dates for Albia, IA

NOAA weather station Albia 3 NNE (USC00130112), Iowa · elevation 880 ft (268 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 9only 1 spring in 10 still has a frost later
  • Typical last frostApril 2450% chance of a frost after it
  • Typical first fall frostOctober 1650% chance of a frost before it
  • Frost-free season173 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Albia, IASpring: a frost after April 8 in 9 years out of 10, after April 24 in half of the years, after May 9 in 1 year out of 10. Fall: the first frost comes before September 29 in 1 year out of 10, before October 16 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 173 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 24First frost ~Oct 16Frost season at Albia, IASpring: a frost after April 8 in 9 years out of 10, after April 24 in half of the years, after May 9 in 1 year out of 10. Fall: the first frost comes before September 29 in 1 year out of 10, before October 16 in half of the years, before October 28 in 9 years out of 10. Typical frost-free season: 173 days.JFMAMJJASONDLast frost ~Apr 24First 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.Today

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)May 9September 29
50% (typical)April 24October 16
90% (likely)April 8October 28
Frost-free season (32°F, 50% chance)
173 days
Hard frost (28°F), last in spring, 50% chance after
April 12
Hard frost (28°F), first in fall, 50% chance before
October 26

The last 15 years (2006–2020 normals)

Typical last frost April 24 (same as the 30-year normal), typical first fall frost October 19 (3 days later). Frost-free season 178 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 Albia: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 9, 20% May 4, 30% May 1, 40% April 28, 50% April 24, 60% April 21, 70% April 18, 80% April 13, 90% April 8.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 9Apr 24Apr 8Fall at Albia: chance of a frost before this dateFall, chance of a frost before the date: 10% September 29, 20% October 4, 30% October 8, 40% October 12, 50% October 16, 60% October 19, 70% October 21, 80% October 24, 90% October 28.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 29Oct 16Oct 28
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 April 8 carries a 90 % chance that a light frost will still occur later, so it is a gamble for Albian gardeners. The cautious spring date is May 9, when only a 10 % chance of frost later remains, and the cautious fall date is September 29, with a 10 % chance of frost earlier. The 50 % dates mark the points where a light frost is equally likely to have happened or not: April 24 in spring and October 16 in fall. Based on 30 years of record, the interval between the two 32 °F 50 % dates—April 24 and October 16—is 173 days. For hard frosts, the 50 % dates are April 12 and October 26. A hard frost at 28 °F can damage plant tissue that would survive a light frost at 32 °F.

How to read the probabilities

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

  • Spring: "10% after May 9" 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 September 29" 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 Albia, IANumbered nearest stations: 1 — near Ottumwa, IA — 18 mi; 2 — Oskaloosa, IA — 19 mi; 3 — Chariton, IA — 26 mi; 4 — Bloomfield, IA — 30 mi; 5 — Sigourney, IA — 35 mi.MO25 mi · 40 km1. near Ottumwa, IA — 18 mi12. Oskaloosa, IA — 19 mi23. Chariton, IA — 26 mi34. Bloomfield, IA — 30 mi45. Sigourney, IA — 35 mi5
  1. near Ottumwa, IA 18 mi (29 km)
  2. Oskaloosa, IA 19 mi (31 km)
  3. Chariton, IA 26 mi (42 km)
  4. Bloomfield, IA 30 mi (48 km)
  5. Sigourney, IA 35 mi (56 km)

Sources

* Hardiness zone 5b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 41.0656, -92.7867.