U.S. Frost Dates by Weather Station

NOAA station USC00251365 · Nebraska

Frost Dates for Butte, NE

NOAA weather station Butte (USC00251365), Nebraska · elevation 1806 ft (551 m) · hardiness zone 5a*

  • Lower-risk planting dateafter May 17only 1 spring in 10 still has a frost later
  • Typical last frostMay 450% chance of a frost after it
  • Typical first fall frostOctober 650% chance of a frost before it
  • Frost-free season152 daystypical year, 32°F
  • Hardiness zone5acalculated*

The year at a glance

Frost season at Butte, NESpring: a frost after April 21 in 9 years out of 10, after May 4 in half of the years, after May 17 in 1 year out of 10. Fall: the first frost comes before September 23 in 1 year out of 10, before October 6 in half of the years, before October 19 in 9 years out of 10. Typical frost-free season: 152 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 4First frost ~Oct 6Frost season at Butte, NESpring: a frost after April 21 in 9 years out of 10, after May 4 in half of the years, after May 17 in 1 year out of 10. Fall: the first frost comes before September 23 in 1 year out of 10, before October 6 in half of the years, before October 19 in 9 years out of 10. Typical frost-free season: 152 days.JFMAMJJASONDLast frost ~May 4First frost ~Oct 6
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 30 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 17September 23
50% (typical)May 4October 6
90% (likely)April 21October 19
Frost-free season (32°F, 50% chance)
152 days
Hard frost (28°F), last in spring, 50% chance after
April 25
Hard frost (28°F), first in fall, 50% chance before
October 15

The last 15 years (2006–2020 normals)

Typical last frost May 4 (same as the 30-year normal), typical first fall frost October 10 (4 days later). Frost-free season 159 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 Butte: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 17, 20% May 12, 30% May 9, 40% May 6, 50% May 4, 60% May 2, 70% April 30, 80% April 26, 90% April 21. Observed last spring frost in recent years: 2021 May 12.Spring: last frostChance of a frost after this date10%50%90%May 1May 17May 4Apr 212021: May 12Fall at Butte: chance of a frost before this dateFall, chance of a frost before the date: 10% September 23, 20% September 28, 30% October 1, 40% October 3, 50% October 6, 60% October 9, 70% October 12, 80% October 15, 90% October 19. Observed first fall frost in recent years: 2021 October 16.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 23Oct 6Oct 192021: October 16
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
2021May 12October 16
2022incomplete recordno data
2023no datano data
2024no datano data
2025no datano data
2026no dataseason not over yet

What these dates mean

September 23 marks the cautious fall date for finishing the harvest of tender crops in Butte; there is only a 10 % chance that a light frost has arrived earlier. A later date such as October 19 carries a 90 % chance of frost already occurring, while October 6 is the 50 % date, meaning a 50 % chance of a frost earlier than this date.

Gardeners who wait until May 17 in spring use the cautious date for setting out tender crops, because only a 10 % chance of light frost remains after that date. The 50 % date of May 4 represents a 50 % chance of a frost later than this date, and April 21 is a gamble with a 90 % chance of frost. The 50 % hard-frost dates are April 25 in spring and October 15 in fall; a hard frost at 28 °F can injure plants that survive a light frost at 32 °F, making it a more critical threshold. The period between the two 32 °F 50 % dates spans 152 days, based on 30 years of record.

How to read the probabilities

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

  • Spring: "10% after May 17" 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 23" 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 Butte, NENumbered nearest stations: 1 — Pickstown, SD — 19 mi; 2 — Lynch, NE — 20 mi; 3 — Atkinson, NE — 29 mi; 4 — Newport, NE — 33 mi; 5 — O'Neill, NE — 33 mi.SD25 mi · 40 km1. Pickstown, SD — 19 mi12. Lynch, NE — 20 mi23. Atkinson, NE — 29 mi34. Newport, NE — 33 mi45. O'Neill, NE — 33 mi5
  1. Pickstown, SD 19 mi (31 km)
  2. Lynch, NE 20 mi (32 km)
  3. Atkinson, NE 29 mi (47 km)
  4. Newport, NE 33 mi (52 km)
  5. O'Neill, NE 33 mi (53 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: 42.9131, -98.8511.