U.S. Frost Dates by Weather Station

NOAA station USC00447925 · Virginia

Frost Dates for South Boston, VA

NOAA weather station South Boston (USC00447925), Virginia · elevation 329 ft (100 m) · hardiness zone 7b*

  • Lower-risk planting dateafter April 30only 1 spring in 10 still has a frost later
  • Typical last frostApril 1050% chance of a frost after it
  • Typical first fall frostOctober 3050% chance of a frost before it
  • Frost-free season202 daystypical year, 32°F
  • Hardiness zone7bcalculated*

The year at a glance

Frost season at South Boston, VASpring: a frost after March 25 in 9 years out of 10, after April 10 in half of the years, after April 30 in 1 year out of 10. Fall: the first frost comes before October 17 in 1 year out of 10, before October 30 in half of the years, before November 12 in 9 years out of 10. Typical frost-free season: 202 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 10First frost ~Oct 30Frost season at South Boston, VASpring: a frost after March 25 in 9 years out of 10, after April 10 in half of the years, after April 30 in 1 year out of 10. Fall: the first frost comes before October 17 in 1 year out of 10, before October 30 in half of the years, before November 12 in 9 years out of 10. Typical frost-free season: 202 days.JFMAMJJASONDLast frost ~Apr 10First frost ~Oct 30
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)April 30October 17
50% (typical)April 10October 30
90% (likely)March 25November 12
Frost-free season (32°F, 50% chance)
202 days
Hard frost (28°F), last in spring, 50% chance after
March 29
Hard frost (28°F), first in fall, 50% chance before
November 7

The last 15 years (2006–2020 normals)

Typical last frost April 8 (2 days earlier than the 30-year normal), typical first fall frost November 1 (2 days later). Frost-free season 205 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 South Boston: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 30, 20% April 22, 30% April 17, 40% April 13, 50% April 10, 60% April 7, 70% April 3, 80% March 31, 90% March 25. Observed last spring frost in recent years: 2021 April 24, 2022 April 21, 2023 April 12, 2024 April 8, 2025 April 11, 2026 April 22.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 30Apr 10Mar 252021: April 242022: April 212023: April 122024: April 82025: April 112026: April 22Fall at South Boston: chance of a frost before this dateFall, chance of a frost before the date: 10% October 17, 20% October 22, 30% October 25, 40% October 28, 50% October 30, 60% November 1, 70% November 3, 80% November 6, 90% November 12. Observed first fall frost in recent years: 2021 November 5, 2022 October 19, 2023 November 2, 2024 November 17, 2025 October 25.Fall: first frostChance of a frost before this date10%50%90%Nov 1Oct 17Oct 30Nov 122021: November 52022: October 192023: November 22024: November 172025: October 25
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
2021April 24November 5
2022April 21October 19
2023April 12November 2
2024April 8November 17
2025April 11October 25
2026April 22season not over yet

What these dates mean

The 202-day span between the 32°F 50% dates in South Boston—April 10 and October 30—covers the period in which light frosts are equally likely to occur before or after each date, giving gardeners a central window for planning.

For a cautious schedule, tender crops should be set out after the April 30 date, which carries only a 10 % chance of a later light frost, and should be finished by October 17, which also holds a 10 % chance of an earlier light frost. Planting earlier on March 25 or later on November 12 involves a 90 % chance of frost and is therefore a gamble.

A hard frost at 28°F—recorded median on March 29 in spring and November 7 in fall—can injure plants that survive a light frost, so it is a more critical threshold for gardeners.

How to read the probabilities

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

  • Spring: "10% after April 30" 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 17" 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 South Boston, VANumbered nearest stations: 1 — Chatham, VA — 31 mi; 2 — near Bracey, VA — 33 mi; 3 — Lynchburg, VA — 47 mi; 4 — Reidsville, NC — 50 mi; 5 — Chapel Hill, NC — 55 mi.VANC25 mi · 40 km1. Chatham, VA — 31 mi12. near Bracey, VA — 33 mi23. Lynchburg, VA — 47 mi34. Reidsville, NC — 50 mi45. Chapel Hill, NC — 55 mi5
  1. Chatham, VA 31 mi (49 km)
  2. near Bracey, VA 33 mi (53 km)
  3. Lynchburg, VA 47 mi (75 km)
  4. Reidsville, NC 50 mi (81 km)
  5. Chapel Hill, NC 55 mi (89 km)

Sources

* Hardiness zone 7b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 36.6953, -78.8808.