U.S. Frost Dates by Weather Station

NOAA station USC00218450 · Minnesota

Frost Dates near Roseville, MN

NOAA weather station University of MN St. Paul (USC00218450), Minnesota · elevation 970 ft (296 m) · hardiness zone 5a*

Roseville is the nearest town to the station (1.6 mi away) in GeoNames (CC BY 4.0). The dates below are measured at the station, not in the town itself.

  • Lower-risk planting dateafter May 14only 1 spring in 10 still has a frost later
  • Typical last frostApril 2850% chance of a frost after it
  • Typical first fall frostOctober 850% chance of a frost before it
  • Frost-free season162 daystypical year, 32°F
  • Hardiness zone5acalculated*

The year at a glance

Frost season near Roseville, MNSpring: a frost after April 14 in 9 years out of 10, after April 28 in half of the years, after May 14 in 1 year out of 10. Fall: the first frost comes before September 25 in 1 year out of 10, before October 8 in half of the years, before October 22 in 9 years out of 10. Typical frost-free season: 162 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 28First frost ~Oct 8Frost season near Roseville, MNSpring: a frost after April 14 in 9 years out of 10, after April 28 in half of the years, after May 14 in 1 year out of 10. Fall: the first frost comes before September 25 in 1 year out of 10, before October 8 in half of the years, before October 22 in 9 years out of 10. Typical frost-free season: 162 days.JFMAMJJASONDLast frost ~Apr 28First frost ~Oct 8
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 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 14September 25
50% (typical)April 28October 8
90% (likely)April 14October 22
Frost-free season (32°F, 50% chance)
162 days
Hard frost (28°F), last in spring, 50% chance after
April 18
Hard frost (28°F), first in fall, 50% chance before
October 21

The last 15 years (2006–2020 normals)

Typical last frost April 28 (same as the 30-year normal), typical first fall frost October 14 (6 days later). Frost-free season 168 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 near Roseville: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 14, 20% May 7, 30% May 4, 40% April 30, 50% April 28, 60% April 25, 70% April 22, 80% April 18, 90% April 14. Observed last spring frost in recent years: 2021 April 25, 2022 April 28, 2023 April 26, 2024 April 24, 2025 April 19, 2026 May 7.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 14Apr 28Apr 142021: April 252022: April 282023: April 262024: April 242025: April 192026: May 7Fall near Roseville: chance of a frost before this dateFall, chance of a frost before the date: 10% September 25, 20% September 29, 30% October 2, 40% October 5, 50% October 8, 60% October 11, 70% October 15, 80% October 19, 90% October 22. Observed first fall frost in recent years: 2021 October 22, 2022 October 8, 2023 October 28, 2024 October 14, 2025 October 24.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 25Oct 8Oct 222021: October 222022: October 82023: October 282024: October 142025: October 24
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 25October 22
2022April 28October 8
2023April 26October 28
2024April 24October 14
2025April 19October 24
2026May 7season not over yet

What these dates mean

The 162 days between the 50% dates in the Roseville area—April 28 and October 8—frame the period when a light frost (32 °F) is less likely than not, giving gardeners a window for most outdoor work.

In spring the cautious date for setting out tender crops is May 14, when there is only a 10 % chance of a frost later; planting on April 14 carries a 90 % chance of a later frost and is a gamble. In fall the cautious date to finish harvesting tender crops is September 25, with only a 10 % chance that a frost has arrived earlier, while waiting until October 22 involves a 90 % chance of an earlier frost.

Hard-frost thresholds are marked by the 50% dates April 18 and October 21; a 28 °F frost can damage plant tissue more severely than a 32 °F light frost, so it is a more critical concern for growers.

How to read the probabilities

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

  • Spring: "10% after May 14" 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 25" 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 Roseville, MNNumbered nearest stations: 1 — Lower St. Anthony Falls, MN — 3 mi; 2 — Minneapolis (Minneapolis/St. Paul Airport), MN — 8 mi; 3 — New Hope, MN — 10 mi; 4 — Rosemount, MN — 19 mi; 5 — Chanhassen, MN — 21 mi.WI25 mi · 40 km1. Lower St. Anthony Falls, MN — 3 mi12. Minneapolis (Minneapolis/St. Paul Airport), MN — 8 mi23. New Hope, MN — 10 mi34. Rosemount, MN — 19 mi45. Chanhassen, MN — 21 mi5
  1. Lower St. Anthony Falls, MN 3 mi (5 km)
  2. Minneapolis (Minneapolis/St. Paul Airport), MN 8 mi (13 km)
  3. New Hope, MN 10 mi (16 km)
  4. Rosemount, MN 19 mi (31 km)
  5. Chanhassen, MN 21 mi (34 km)

Sources

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

Station coordinates: 44.9903, -93.18.