U.S. Frost Dates by Weather Station

NOAA station USC00402589 · Tennessee

Frost Dates for Dover, TN

NOAA weather station Dover 1 W (USC00402589), Tennessee · elevation 475 ft (145 m) · hardiness zone 7b*

  • Lower-risk planting dateafter April 21only 1 spring in 10 still has a frost later
  • Typical last frostApril 450% chance of a frost after it
  • Typical first fall frostOctober 3150% chance of a frost before it
  • Frost-free season210 daystypical year, 32°F
  • Hardiness zone7bcalculated*

The year at a glance

Frost season at Dover, TNSpring: a frost after March 17 in 9 years out of 10, after April 4 in half of the years, after April 21 in 1 year out of 10. Fall: the first frost comes before October 18 in 1 year out of 10, before October 31 in half of the years, before November 15 in 9 years out of 10. Typical frost-free season: 210 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 4First frost ~Oct 31Frost season at Dover, TNSpring: a frost after March 17 in 9 years out of 10, after April 4 in half of the years, after April 21 in 1 year out of 10. Fall: the first frost comes before October 18 in 1 year out of 10, before October 31 in half of the years, before November 15 in 9 years out of 10. Typical frost-free season: 210 days.JFMAMJJASONDLast frost ~Apr 4First frost ~Oct 31
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)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)April 21October 18
50% (typical)April 4October 31
90% (likely)March 17November 15
Frost-free season (32°F, 50% chance)
210 days
Hard frost (28°F), last in spring, 50% chance after
March 23
Hard frost (28°F), first in fall, 50% chance before
November 11

The last 15 years (2006–2020 normals)

Typical last frost April 6 (2 days later than the 30-year normal), typical first fall frost November 1 (1 day later). Frost-free season 210 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 Dover: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 21, 20% April 15, 30% April 10, 40% April 8, 50% April 4, 60% April 1, 70% March 29, 80% March 24, 90% March 17. Observed last spring frost in recent years: 2021 April 3, 2022 April 7, 2025 April 10.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Apr 21Apr 4Mar 172021: April 32022: April 72025: April 10Fall at Dover: chance of a frost before this dateFall, chance of a frost before the date: 10% October 18, 20% October 23, 30% October 26, 40% October 29, 50% October 31, 60% November 2, 70% November 5, 80% November 9, 90% November 15. Observed first fall frost in recent years: 2021 November 4.Fall: first frostChance of a frost before this date10%50%90%Nov 1Oct 18Oct 31Nov 152021: November 4
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 3November 4
2022April 7incomplete record
2023incomplete recordincomplete record
2024incomplete recordincomplete record
2025April 10incomplete record
2026incomplete recordseason not over yet

What these dates mean

In Dover, Tennessee there are 210 days between the 32°F 50% dates, April 4 and October 31, marking a span where a light frost is equally likely to occur before or after each date. The 50% date in spring means a 50 % chance of a frost later than April 4, while the 50% date in fall means a 50 % chance of a frost earlier than October 31.

The cautious spring date for tender crops is April 21, when only a 10 % chance of a later frost remains; planting on March 17 carries a 90 % chance of a frost and is a gamble. In the fall the cautious date to finish harvesting tender crops is October 18, with just a 10 % chance that a frost has already arrived, whereas November 15 is a gamble with a 90 % chance of an earlier frost. A hard frost, recorded by the 28°F 50% dates of March 23 and November 11, can damage plants more severely than a light frost because it reaches a lower 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 April 21" 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 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

Map of weather stations near Dover, TNNumbered nearest stations: 1 — Murray, KY — 26 mi; 2 — Clarksville, TN — 30 mi; 3 — Dickson, TN — 38 mi; 4 — Princeton, KY — 44 mi; 5 — Huntingdon, TN — 46 mi.TNKYILMO25 mi · 40 km1. Murray, KY — 26 mi12. Clarksville, TN — 30 mi23. Dickson, TN — 38 mi34. Princeton, KY — 44 mi45. Huntingdon, TN — 46 mi5
  1. Murray, KY 26 mi (42 km)
  2. Clarksville, TN 30 mi (48 km)
  3. Dickson, TN 38 mi (62 km)
  4. Princeton, KY 44 mi (71 km)
  5. Huntingdon, TN 46 mi (73 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: 36.4819, -87.8628.