NOAA station USC00304808 · New York

Frost Dates for Little Valley, NY

NOAA weather station Little Valley (USC00304808), New York · elevation 1625 ft (495 m) · hardiness zone 5b^*

Lower-risk planting dateafter May 31only 1 spring in 10 still has a frost later
Typical last frostMay 1750% chance of a frost after it
Typical first fall frostOctober 150% chance of a frost before it
Frost-free season136 daystypical year, 32°F
Hardiness zone5bcalculated^*

The year at a glance

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 29 years of NOAA records (1991–2020 normals)
Chance	Last frost in spring after	First frost in fall before
10% (unlikely)	May 31	September 18
50% (typical)	May 17	October 1
90% (likely)	May 1	October 17

Frost-free season (32°F, 50% chance): 136 days
Hard frost (28°F), last in spring, 50% chance after: May 3
Hard frost (28°F), first in fall, 50% chance before: October 15

The last 15 years (2006–2020 normals)

Typical last frost May 14 (3 days earlier than the 30-year normal), typical first fall frost October 8 (7 days later). Frost-free season 145 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

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
Year	Last spring frost	First fall frost
2021	May 31	October 20
2022	May 8	September 30
2023	May 27	October 13
2024	June 1	October 11
2025	June 3	October 9
2026	May 13	season not over yet

What these dates mean

September 18 is the cautious fall date for finishing the harvest in Little Valley, carrying only a 10 % chance that a light frost has arrived earlier.

The 50% dates mark the point where a light frost is equally likely to occur later in spring or earlier in fall. The 50% date is May 17 for spring and October 1 for fall. For hard frost, the 50% dates are May 3 in spring and October 15 in fall. A cautious plan for tender crops follows the light-frost cautious dates: May 31 in spring (10 % chance of a later frost) and September 18 in fall (10 % chance of an earlier frost).

A hard frost at 28 °F can injure or kill plants that would survive a 32 °F light frost, making it the more critical temperature 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 31" 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 18" 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

near Allegany, NY 11 mi (17 km)
Franklinville, NY 19 mi (30 km)
Jamestown, NY 20 mi (32 km)
Bradford 4 SW Research 5, PA 25 mi (40 km)
Bradford, PA 32 mi (51 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: 42.2472, -78.8125.