U.S. Frost Dates by Weather Station

NOAA station USC00300093 · New York

Frost Dates near Allegany, NY

NOAA weather station Allegany State Park (USC00300093), New York · elevation 1500 ft (457 m) · hardiness zone 5b*

Allegany is the nearest town to the station (13.1 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 28only 1 spring in 10 still has a frost later
  • Typical last frostMay 1250% chance of a frost after it
  • Typical first fall frostOctober 950% chance of a frost before it
  • Frost-free season150 daystypical year, 32°F
  • Hardiness zone5bcalculated*

The year at a glance

Frost season near Allegany, NYSpring: a frost after April 27 in 9 years out of 10, after May 12 in half of the years, after May 28 in 1 year out of 10. Fall: the first frost comes before September 28 in 1 year out of 10, before October 9 in half of the years, before October 24 in 9 years out of 10. Typical frost-free season: 150 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 12First frost ~Oct 9Frost season near Allegany, NYSpring: a frost after April 27 in 9 years out of 10, after May 12 in half of the years, after May 28 in 1 year out of 10. Fall: the first frost comes before September 28 in 1 year out of 10, before October 9 in half of the years, before October 24 in 9 years out of 10. Typical frost-free season: 150 days.JFMAMJJASONDLast frost ~May 12First frost ~Oct 9
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 28September 28
50% (typical)May 12October 9
90% (likely)April 27October 24
Frost-free season (32°F, 50% chance)
150 days
Hard frost (28°F), last in spring, 50% chance after
April 30
Hard frost (28°F), first in fall, 50% chance before
October 23

The last 15 years (2006–2020 normals)

Typical last frost May 10 (2 days earlier than the 30-year normal), typical first fall frost October 15 (6 days later). Frost-free season 155 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 Allegany: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 28, 20% May 23, 30% May 19, 40% May 16, 50% May 12, 60% May 8, 70% May 4, 80% April 30, 90% April 27. Observed last spring frost in recent years: 2021 May 13, 2022 May 8, 2023 May 26, 2024 April 27, 2025 June 2, 2026 May 13.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 28May 12Apr 272021: May 132022: May 82023: May 262024: April 272025: June 22026: May 13Fall near Allegany: chance of a frost before this dateFall, chance of a frost before the date: 10% September 28, 20% October 1, 30% October 3, 40% October 6, 50% October 9, 60% October 12, 70% October 16, 80% October 19, 90% October 24. Observed first fall frost in recent years: 2021 October 29, 2022 September 30, 2023 November 1, 2024 October 11, 2025 October 9.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Sep 28Oct 9Oct 242021: October 292022: September 302023: November 12024: October 112025: October 9
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 13October 29
2022May 8September 30
2023May 26November 1
2024April 27October 11
2025June 2October 9
2026May 13season not over yet

What these dates mean

May 28 marks the cautious spring date for the Allegany area, giving gardeners a 10% chance of a light frost later and allowing them to set out tender crops with relatively low risk. The cautious fall date is September 28, when there is only a 10% chance that a light frost has arrived earlier, so finishing harvesting tender crops by then keeps risk minimal.

The 50% date in spring is May 12; there is a 50% chance of a light frost later than this date. The 50% date in fall is October 9; there is a 50% chance of a light frost earlier than this date. The hard-frost median dates are April 30 in spring and October 23 in fall, and a hard frost at 28 °F can damage vegetation more severely than the lighter 32 °F frost.

How to read the probabilities

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

  • Spring: "10% after May 28" 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 28" 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 Allegany, NYNumbered nearest stations: 1 — Little Valley, NY — 11 mi; 2 — Bradford 4 SW Research 5, PA — 14 mi; 3 — Jamestown, NY — 21 mi; 4 — Bradford, PA — 21 mi; 5 — Franklinville, NY — 22 mi.PA25 mi · 40 km1. Little Valley, NY — 11 mi12. Bradford 4 SW Research 5, PA — 14 mi23. Jamestown, NY — 21 mi34. Bradford, PA — 21 mi45. Franklinville, NY — 22 mi5
  1. Little Valley, NY 11 mi (17 km)
  2. Bradford 4 SW Research 5, PA 14 mi (23 km)
  3. Jamestown, NY 21 mi (34 km)
  4. Bradford, PA 21 mi (34 km)
  5. Franklinville, NY 22 mi (35 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: 42.1003, -78.7497.