U.S. Frost Dates by Weather Station

NOAA station USC00251415 · Nebraska

Frost Dates for Cambridge, NE

NOAA weather station Cambridge (USC00251415), Nebraska · elevation 2239 ft (682 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 15only 1 spring in 10 still has a frost later
  • Typical last frostMay 350% chance of a frost after it
  • Typical first fall frostOctober 550% chance of a frost before it
  • Frost-free season156 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Cambridge, NESpring: a frost after April 20 in 9 years out of 10, after May 3 in half of the years, after May 15 in 1 year out of 10. Fall: the first frost comes before September 24 in 1 year out of 10, before October 5 in half of the years, before October 18 in 9 years out of 10. Typical frost-free season: 156 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 3First frost ~Oct 5Frost season at Cambridge, NESpring: a frost after April 20 in 9 years out of 10, after May 3 in half of the years, after May 15 in 1 year out of 10. Fall: the first frost comes before September 24 in 1 year out of 10, before October 5 in half of the years, before October 18 in 9 years out of 10. Typical frost-free season: 156 days.JFMAMJJASONDLast frost ~May 3First frost ~Oct 5
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)May 15September 24
50% (typical)May 3October 5
90% (likely)April 20October 18
Frost-free season (32°F, 50% chance)
156 days
Hard frost (28°F), last in spring, 50% chance after
April 23
Hard frost (28°F), first in fall, 50% chance before
October 16

The last 15 years (2006–2020 normals)

Typical last frost May 3 (same as the 30-year normal), typical first fall frost October 8 (3 days later). Frost-free season 157 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 Cambridge: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 15, 20% May 11, 30% May 8, 40% May 5, 50% May 3, 60% May 1, 70% April 29, 80% April 25, 90% April 20. Observed last spring frost in recent years: 2021 May 10, 2022 May 3, 2023 May 4, 2024 April 22, 2025 May 4, 2026 May 3.Spring: last frostChance of a frost after this date10%50%90%May 1May 15May 3Apr 202021: May 102022: May 32023: May 42024: April 222025: May 42026: May 3Fall at Cambridge: chance of a frost before this dateFall, chance of a frost before the date: 10% September 24, 20% September 29, 30% October 1, 40% October 3, 50% October 5, 60% October 8, 70% October 11, 80% October 14, 90% October 18. Observed first fall frost in recent years: 2021 October 14, 2022 October 17, 2023 October 7, 2024 October 14, 2025 October 19.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 24Oct 5Oct 182021: October 142022: October 172023: October 72024: October 142025: October 19
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 10October 14
2022May 3October 17
2023May 4October 7
2024April 22October 14
2025May 4October 19
2026May 3season not over yet

What these dates mean

Setting out tender crops on April 20 in Cambridge carries a 90% chance that a light frost will still occur later, making it a gamble for spring planting. A cautious plan waits until May 15, when the chance of a later frost drops to 10%.

To finish tender crops in the fall, the cautious date is September 24, when only a 10% chance exists that a light frost has already arrived. The 50% spring date is May 3, giving a gardener an even chance of a light frost later, and the 50% fall date is October 5, giving an even chance of a light frost earlier. The 50% hard-frost dates are April 23 in spring and October 16 in fall; hard frosts can damage plants that survive a light frost, so they represent a higher risk.

How to read the probabilities

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

  • Spring: "10% after May 15" 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 24" 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 Cambridge, NENumbered nearest stations: 1 — Beaver City, NE — 20 mi; 2 — Norton Dam, KS — 34 mi; 3 — Culbertson, NE — 36 mi; 4 — near Lexington, NE — 37 mi; 5 — Norton, KS — 41 mi.NEKS25 mi · 40 km1. Beaver City, NE — 20 mi12. Norton Dam, KS — 34 mi23. Culbertson, NE — 36 mi34. near Lexington, NE — 37 mi45. Norton, KS — 41 mi5
  1. Beaver City, NE 20 mi (32 km)
  2. Norton Dam, KS 34 mi (55 km)
  3. Culbertson, NE 36 mi (59 km)
  4. near Lexington, NE 37 mi (59 km)
  5. Norton, KS 41 mi (66 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: 40.2847, -100.1433.