U.S. Frost Dates by Weather Station

NOAA station USC00306085 · New York

Frost Dates for Norwich, NY

NOAA weather station Norwich (USC00306085), New York · elevation 989 ft (301 m) · hardiness zone 5b*

  • Lower-risk planting dateafter May 27only 1 spring in 10 still has a frost later
  • Typical last frostMay 1350% chance of a frost after it
  • Typical first fall frostOctober 450% chance of a frost before it
  • Frost-free season142 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season at Norwich, NYSpring: a frost after April 28 in 9 years out of 10, after May 13 in half of the years, after May 27 in 1 year out of 10. Fall: the first frost comes before September 20 in 1 year out of 10, before October 4 in half of the years, before October 18 in 9 years out of 10. Typical frost-free season: 142 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 13First frost ~Oct 4Frost season at Norwich, NYSpring: a frost after April 28 in 9 years out of 10, after May 13 in half of the years, after May 27 in 1 year out of 10. Fall: the first frost comes before September 20 in 1 year out of 10, before October 4 in half of the years, before October 18 in 9 years out of 10. Typical frost-free season: 142 days.JFMAMJJASONDLast frost ~May 13First frost ~Oct 4
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 27September 20
50% (typical)May 13October 4
90% (likely)April 28October 18
Frost-free season (32°F, 50% chance)
142 days
Hard frost (28°F), last in spring, 50% chance after
May 1
Hard frost (28°F), first in fall, 50% chance before
October 15

The last 15 years (2006–2020 normals)

Typical last frost May 9 (4 days earlier than the 30-year normal), typical first fall frost October 12 (8 days later). Frost-free season 152 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 Norwich: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 27, 20% May 23, 30% May 20, 40% May 17, 50% May 13, 60% May 10, 70% May 7, 80% May 3, 90% April 28. Observed last spring frost in recent years: 2021 May 15, 2022 May 10, 2023 May 26, 2024 April 27, 2025 April 29.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 27May 13Apr 282021: May 152022: May 102023: May 262024: April 272025: April 29Fall at Norwich: chance of a frost before this dateFall, chance of a frost before the date: 10% September 20, 20% September 25, 30% September 29, 40% October 1, 50% October 4, 60% October 6, 70% October 9, 80% October 13, 90% October 18. Observed first fall frost in recent years: 2021 November 3, 2022 October 18, 2023 October 31, 2024 October 13, 2025 October 10.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 20Oct 4Oct 182021: November 32022: October 182023: October 312024: October 132025: October 10
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 15November 3
2022May 10October 18
2023May 26October 31
2024April 27October 13
2025April 29October 10
2026incomplete recordseason not over yet

What these dates mean

The cautious fall date for finishing the harvest in Norwich is September 20, when there is only a 10 % chance that a light frost has already arrived. For a gardener, the 50 % light-frost dates—May 13 in spring and October 4 in fall—mark the point at which frost is equally likely to occur later (spring) or earlier (fall); they are not frost dates themselves.

In spring the cautious date for setting out tender crops is May 27, a 10 % chance of a frost later; planting on April 28 carries a 90 % chance and is a gamble. The median hard-frost dates are May 1 and October 15, and a hard frost at 28 °F can damage plants that survive a light 32 °F frost, making it the more critical threshold.

How to read the probabilities

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

  • Spring: "10% after May 27" 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 20" 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 Norwich, NYNumbered nearest stations: 1 — Sherburne, NY — 11 mi; 2 — Emmons, NY — 26 mi; 3 — Binghamton, NY — 32 mi; 4 — Cooperstown, NY — 33 mi; 5 — near Ithaca, NY — 48 mi.NY25 mi · 40 km1. Sherburne, NY — 11 mi12. Emmons, NY — 26 mi23. Binghamton, NY — 32 mi34. Cooperstown, NY — 33 mi45. near Ithaca, NY — 48 mi5
  1. Sherburne, NY 11 mi (18 km)
  2. Emmons, NY 26 mi (42 km)
  3. Binghamton, NY 32 mi (52 km)
  4. Cooperstown, NY 33 mi (54 km)
  5. near Ithaca, NY 48 mi (77 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: 42.5117, -75.5197.