U.S. Frost Dates by Weather Station

NOAA station USW00013894 · Alabama

Frost Dates for Mobile, AL

NOAA weather station Mobile (USW00013894), Alabama · elevation 208 ft (63 m) · hardiness zone 9a*

  • Lower-risk planting dateafter March 21only 1 spring in 10 still has a frost later
  • Typical last frostMarch 350% chance of a frost after it
  • Typical first fall frostNovember 2550% chance of a frost before it
  • Frost-free season268 daystypical year, 32°F
  • Hardiness zone9acalculated*

The year at a glance

Frost season at Mobile, ALSpring: a frost after February 6 in 9 years out of 10, after March 3 in half of the years, after March 21 in 1 year out of 10. Fall: the first frost comes before November 8 in 1 year out of 10, before November 25 in half of the years, before December 22 in 9 years out of 10. Typical frost-free season: 268 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 3First frost ~Nov 25Frost season at Mobile, ALSpring: a frost after February 6 in 9 years out of 10, after March 3 in half of the years, after March 21 in 1 year out of 10. Fall: the first frost comes before November 8 in 1 year out of 10, before November 25 in half of the years, before December 22 in 9 years out of 10. Typical frost-free season: 268 days.JFMAMJJASONDLast frost ~Mar 3First frost ~Nov 25
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 30 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)March 21November 8
50% (typical)March 3November 25
90% (likely)February 6December 22
Frost-free season (32°F, 50% chance)
268 days
Hard frost (28°F), last in spring, 50% chance after
February 13
Hard frost (28°F), first in fall, 50% chance before
December 14

The last 15 years (2006–2020 normals)

Typical last frost February 28 (3 days earlier than the 30-year normal), typical first fall frost November 22 (3 days earlier). Frost-free season 267 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 Mobile: chance of a frost after this dateSpring, chance of a frost after the date: 10% March 21, 20% March 16, 30% March 12, 40% March 8, 50% March 3, 60% February 27, 70% February 22, 80% February 15, 90% February 6. Observed last spring frost in recent years: 2021 February 23, 2022 March 13, 2023 March 20, 2024 February 19, 2025 March 21, 2026 March 18.Spring: last frostChance of a frost after this date10%50%90%Feb 1Mar 1Apr 1Mar 21Mar 3Feb 62021: February 232022: March 132023: March 202024: February 192025: March 212026: March 18Fall at Mobile: chance of a frost before this dateFall, chance of a frost before the date: 10% November 8, 20% November 13, 30% November 17, 40% November 21, 50% November 25, 60% December 1, 70% December 4, 80% December 10, 90% December 22. Observed first fall frost in recent years: 2021 November 27, 2022 November 18, 2023 November 29, 2024 November 30, 2025 November 10.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Jan 1Nov 8Nov 25Dec 222021: November 272022: November 182023: November 292024: November 302025: November 10
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
2021February 23November 27
2022March 13November 18
2023March 20November 29
2024February 19November 30
2025March 21November 10
2026March 18season not over yet

What these dates mean

The cautious fall date in Mobile for finishing the harvest is November 8, when there is only a 10% chance that a light frost has arrived.

The 50% dates are March 3 in spring and November 25 in fall – they mark the points at which a gardener faces an even chance of a frost occurring later (spring) or earlier (fall). They are not frost events themselves but serve as a statistical midpoint of the 30-year record. The 50% hard-frost dates are February 13 and December 14; a hard frost at 28 °F can damage plant tissue that survives a 32 °F light frost, so it is a more critical threshold for tender crops.

A cautious planting plan therefore uses the March 21 light-frost date, which carries a 10% chance of frost later, for setting out tender crops in spring, and the November 8 date for concluding harvest in fall.

How to read the probabilities

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

  • Spring: "10% after March 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 November 8" 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 Mobile, ALNumbered nearest stations: 1 — Fairhope, AL — 23 mi; 2 — Bay Minette, AL — 30 mi; 3 — Robertsdale, AL — 33 mi; 4 — Beaumont Expstation, MS — 56 mi; 5 — Atmore, AL — 59 mi.MSFL25 mi · 40 km1. Fairhope, AL — 23 mi12. Bay Minette, AL — 30 mi23. Robertsdale, AL — 33 mi34. Beaumont Expstation, MS — 56 mi45. Atmore, AL — 59 mi5
  1. Fairhope, AL 23 mi (37 km)
  2. Bay Minette, AL 30 mi (49 km)
  3. Robertsdale, AL 33 mi (53 km)
  4. Beaumont Expstation, MS 56 mi (90 km)
  5. Atmore, AL 59 mi (95 km)

Sources

* Hardiness zone 9a: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 30.6794, -88.2397.