U.S. Frost Dates by Weather Station

NOAA station USC00469458 · West Virginia

Frost Dates for West Union, WV

NOAA weather station West Union 2 (USC00469458), West Virginia · elevation 806 ft (246 m) · hardiness zone 6b*

  • Lower-risk planting dateafter May 16only 1 spring in 10 still has a frost later
  • Typical last frostApril 2850% chance of a frost after it
  • Typical first fall frostOctober 2150% chance of a frost before it
  • Frost-free season176 daystypical year, 32°F
  • Hardiness zone6bcalculated*

The year at a glance

Frost season at West Union, WVSpring: a frost after April 14 in 9 years out of 10, after April 28 in half of the years, after May 16 in 1 year out of 10. Fall: the first frost comes before October 7 in 1 year out of 10, before October 21 in half of the years, before October 31 in 9 years out of 10. Typical frost-free season: 176 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 28First frost ~Oct 21Frost season at West Union, WVSpring: a frost after April 14 in 9 years out of 10, after April 28 in half of the years, after May 16 in 1 year out of 10. Fall: the first frost comes before October 7 in 1 year out of 10, before October 21 in half of the years, before October 31 in 9 years out of 10. Typical frost-free season: 176 days.JFMAMJJASONDLast frost ~Apr 28First frost ~Oct 21
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 16October 7
50% (typical)April 28October 21
90% (likely)April 14October 31
Frost-free season (32°F, 50% chance)
176 days
Hard frost (28°F), last in spring, 50% chance after
April 15
Hard frost (28°F), first in fall, 50% chance before
October 30

The last 15 years (2006–2020 normals)

Typical last frost April 26 (2 days earlier than the 30-year normal), typical first fall frost October 23 (2 days later). Frost-free season 179 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 West Union: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 16, 20% May 9, 30% May 5, 40% May 1, 50% April 28, 60% April 25, 70% April 21, 80% April 19, 90% April 14. Observed last spring frost in recent years: 2021 May 14, 2024 April 1.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 16Apr 28Apr 142021: May 142024: April 1Fall at West Union: chance of a frost before this dateFall, chance of a frost before the date: 10% October 7, 20% October 12, 30% October 15, 40% October 18, 50% October 21, 60% October 23, 70% October 26, 80% October 28, 90% October 31. Observed first fall frost in recent years: 2021 November 3, 2023 November 2.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 7Oct 21Oct 312021: November 32023: November 2
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 14November 3
2022incomplete recordincomplete record
2023incomplete recordNovember 2
2024April 1incomplete record
2025incomplete recordincomplete record
2026incomplete recordseason not over yet

What these dates mean

The 176 days between the 50% dates in West Union bracket the span when light frost is equally likely to have occurred or not, giving gardeners a clear window for planting. The median light-frost dates are April 28 in spring and October 21 in fall; they are not frost dates but mark the point of even odds.

In spring, a cautious plan would wait until May 16, the 10 % chance date, before setting out tender crops, while planting on April 14 carries a 90 % chance and is a gamble. In fall, the cautious date to finish harvesting tender crops is October 7, the 10 % chance date, whereas planting on October 31 involves a 90 % chance of frost and is risky.

Hard frost at 28 °F, with median dates April 15 and October 30, matters more than a light frost at 32 °F because the lower temperature can damage plants that survive the milder chill.

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 7" 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 West Union, WVNumbered nearest stations: 1 — Middlebourne, WV — 13 mi; 2 — Glenville, WV — 25 mi; 3 — Hannibal Locks & Dam, OH — 27 mi; 4 — Fairmont, WV — 36 mi; 5 — near Williamstown, WV — 36 mi.WVOHPA25 mi · 40 km1. Middlebourne, WV — 13 mi12. Glenville, WV — 25 mi23. Hannibal Locks & Dam, OH — 27 mi34. Fairmont, WV — 36 mi45. near Williamstown, WV — 36 mi5
  1. Middlebourne, WV 13 mi (21 km)
  2. Glenville, WV 25 mi (40 km)
  3. Hannibal Locks & Dam, OH 27 mi (43 km)
  4. Fairmont, WV 36 mi (58 km)
  5. near Williamstown, WV 36 mi (58 km)

Sources

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

Station coordinates: 39.2906, -80.7686.