U.S. Frost Dates by Weather Station

NOAA station USC00317924 · North Carolina

Frost Dates for Siler City, NC

NOAA weather station Siler City 2 N (USC00317924), North Carolina · elevation 610 ft (186 m) · hardiness zone 8a*

  • Lower-risk planting dateafter April 13only 1 spring in 10 still has a frost later
  • Typical last frostMarch 3150% chance of a frost after it
  • Typical first fall frostNovember 450% chance of a frost before it
  • Frost-free season220 daystypical year, 32°F
  • Hardiness zone8acalculated*

The year at a glance

Frost season at Siler City, NCSpring: a frost after March 14 in 9 years out of 10, after March 31 in half of the years, after April 13 in 1 year out of 10. Fall: the first frost comes before October 23 in 1 year out of 10, before November 4 in half of the years, before November 20 in 9 years out of 10. Typical frost-free season: 220 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 31First frost ~Nov 4Frost season at Siler City, NCSpring: a frost after March 14 in 9 years out of 10, after March 31 in half of the years, after April 13 in 1 year out of 10. Fall: the first frost comes before October 23 in 1 year out of 10, before November 4 in half of the years, before November 20 in 9 years out of 10. Typical frost-free season: 220 days.JFMAMJJASONDLast frost ~Mar 31First frost ~Nov 4
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 28 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 13October 23
50% (typical)March 31November 4
90% (likely)March 14November 20
Frost-free season (32°F, 50% chance)
220 days
Hard frost (28°F), last in spring, 50% chance after
March 17
Hard frost (28°F), first in fall, 50% chance before
November 16

The last 15 years (2006–2020 normals)

Typical last frost April 1 (1 day later than the 30-year normal), typical first fall frost November 6 (2 days later). Frost-free season 221 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 Siler City: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 13, 20% April 9, 30% April 5, 40% April 2, 50% March 31, 60% March 27, 70% March 24, 80% March 19, 90% March 14.Spring: last frostChance of a frost after this date10%50%90%Mar 1Apr 1Apr 13Mar 31Mar 14Fall at Siler City: chance of a frost before this dateFall, chance of a frost before the date: 10% October 23, 20% October 28, 30% October 31, 40% November 2, 50% November 4, 60% November 7, 70% November 10, 80% November 13, 90% November 20.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Oct 23Nov 4Nov 20
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.

What these dates mean

April 13 is the cautious spring date in Siler City, and it lets a gardener plan to set out tender crops with only a 10% chance of a light frost later. The early spring date of March 14 carries a 90% chance of a light frost, so planting then is a gamble. The 50% date is March 31, meaning a gardener faces a 50% chance of a light frost later than this date. For hard frost, the 50% date is March 17. In fall, October 23 is the cautious date to finish harvesting tender crops, while the 50% date is November 4, meaning a 50% chance of a light frost earlier than this date, and the hard-frost 50% date is November 16. Hard frost at 28°F can kill tender tissue, making it more damaging than a light frost at 32°F.

How to read the probabilities

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

  • Spring: "10% after April 13" 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 23" 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 Siler City, NCNumbered nearest stations: 1 — Asheboro, NC — 21 mi; 2 — Chapel Hill, NC — 24 mi; 3 — Sanford, NC — 28 mi; 4 — near Greensboro, NC — 36 mi; 5 — Raleigh (Raleigh-Durham Airport), NC — 39 mi.25 mi · 40 km1. Asheboro, NC — 21 mi12. Chapel Hill, NC — 24 mi23. Sanford, NC — 28 mi34. near Greensboro, NC — 36 mi45. Raleigh (Raleigh-Durham Airport), NC — 39 mi5
  1. Asheboro, NC 21 mi (34 km)
  2. Chapel Hill, NC 24 mi (38 km)
  3. Sanford, NC 28 mi (45 km)
  4. near Greensboro, NC 36 mi (57 km)
  5. Raleigh (Raleigh-Durham Airport), NC 39 mi (63 km)

Sources

* Hardiness zone 8a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 35.7608, -79.4625.