U.S. Frost Dates by Weather Station

NOAA station USC00303773 · New York

Frost Dates for Hemlock, NY

NOAA weather station Hemlock (USC00303773), New York · elevation 902 ft (275 m) · hardiness zone 6a*

  • Lower-risk planting dateafter May 16only 1 spring in 10 still has a frost later
  • Typical last frostMay 250% chance of a frost after it
  • Typical first fall frostOctober 1850% chance of a frost before it
  • Frost-free season167 daystypical year, 32°F
  • Hardiness zone6acalculated*

The year at a glance

Frost season at Hemlock, NYSpring: a frost after April 22 in 9 years out of 10, after May 2 in half of the years, after May 16 in 1 year out of 10. Fall: the first frost comes before October 2 in 1 year out of 10, before October 18 in half of the years, before November 3 in 9 years out of 10. Typical frost-free season: 167 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 2First frost ~Oct 18Frost season at Hemlock, NYSpring: a frost after April 22 in 9 years out of 10, after May 2 in half of the years, after May 16 in 1 year out of 10. Fall: the first frost comes before October 2 in 1 year out of 10, before October 18 in half of the years, before November 3 in 9 years out of 10. Typical frost-free season: 167 days.JFMAMJJASONDLast frost ~May 2First frost ~Oct 18
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 16October 2
50% (typical)May 2October 18
90% (likely)April 22November 3
Frost-free season (32°F, 50% chance)
167 days
Hard frost (28°F), last in spring, 50% chance after
April 22
Hard frost (28°F), first in fall, 50% chance before
November 1

The last 15 years (2006–2020 normals)

Typical last frost May 1 (1 day earlier than the 30-year normal), typical first fall frost October 21 (3 days later). Frost-free season 171 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 Hemlock: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 16, 20% May 12, 30% May 8, 40% May 5, 50% May 2, 60% April 30, 70% April 28, 80% April 25, 90% April 22. Observed last spring frost in recent years: 2021 May 1, 2022 May 8, 2023 May 25, 2024 April 26, 2025 April 18, 2026 May 12.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1May 16May 2Apr 222021: May 12022: May 82023: May 252024: April 262025: April 182026: May 12Fall at Hemlock: chance of a frost before this dateFall, chance of a frost before the date: 10% October 2, 20% October 7, 30% October 11, 40% October 14, 50% October 18, 60% October 21, 70% October 25, 80% October 30, 90% November 3. Observed first fall frost in recent years: 2021 November 4, 2022 October 28, 2023 October 31, 2024 October 25, 2025 October 10.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 2Oct 18Nov 32021: November 42022: October 282023: October 312024: October 252025: 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 1November 4
2022May 8October 28
2023May 25October 31
2024April 26October 25
2025April 18October 10
2026May 12season not over yet

What these dates mean

May 16 is the cautious spring light-frost date for Hemlock; with only a 10 % chance that a light frost will occur later, it gives a gardener a reliable point to set out tender crops. The 50 % light-frost dates are May 2 in spring and October 18 in fall; each marks the median moment when a light frost is equally likely to have occurred or not, providing a reference for gauging risk.

For a cautious fall plan, October 2 serves as the early light-frost date with a 10 % chance that a light frost has already arrived, indicating when tender crops should be finished. The hard-frost median dates are April 22 in spring and November 1 in fall; a hard frost at 28 °F can damage plants more severely than a light frost at 32 °F, so these dates are especially important for protecting vulnerable growth.

How to read the probabilities

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

  • Spring: "10% after May 16" 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 October 2" 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 Hemlock, NYNumbered nearest stations: 1 — Honeoye, NY — 5 mi; 2 — Avon, NY — 13 mi; 3 — Dansville, NY — 16 mi; 4 — Canandaigua, NY — 17 mi; 5 — Rochester, NY — 24 mi.25 mi · 40 km1. Honeoye, NY — 5 mi12. Avon, NY — 13 mi23. Dansville, NY — 16 mi34. Canandaigua, NY — 17 mi45. Rochester, NY — 24 mi5
  1. Honeoye, NY 5 mi (8 km)
  2. Avon, NY 13 mi (20 km)
  3. Dansville, NY 16 mi (25 km)
  4. Canandaigua, NY 17 mi (28 km)
  5. Rochester, NY 24 mi (38 km)

Sources

* Hardiness zone 6a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 42.7742, -77.6083.