U.S. Frost Dates by Weather Station

NOAA station USC00185865 · Maryland

Frost Dates for Mechanicsville, MD

NOAA weather station Mechanicsville 5 NE (USC00185865), Maryland · elevation 100 ft (31 m) · hardiness zone 7b*

  • Lower-risk planting dateafter May 2only 1 spring in 10 still has a frost later
  • Typical last frostApril 1750% chance of a frost after it
  • Typical first fall frostOctober 2750% chance of a frost before it
  • Frost-free season195 daystypical year, 32°F
  • Hardiness zone7bcalculated*

The year at a glance

Frost season at Mechanicsville, MDSpring: a frost after March 31 in 9 years out of 10, after April 17 in half of the years, after May 2 in 1 year out of 10. Fall: the first frost comes before October 12 in 1 year out of 10, before October 27 in half of the years, before November 9 in 9 years out of 10. Typical frost-free season: 195 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Apr 17First frost ~Oct 27Frost season at Mechanicsville, MDSpring: a frost after March 31 in 9 years out of 10, after April 17 in half of the years, after May 2 in 1 year out of 10. Fall: the first frost comes before October 12 in 1 year out of 10, before October 27 in half of the years, before November 9 in 9 years out of 10. Typical frost-free season: 195 days.JFMAMJJASONDLast frost ~Apr 17First frost ~Oct 27
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 29 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)May 2October 12
50% (typical)April 17October 27
90% (likely)March 31November 9
Frost-free season (32°F, 50% chance)
195 days
Hard frost (28°F), last in spring, 50% chance after
April 2
Hard frost (28°F), first in fall, 50% chance before
November 6

The last 15 years (2006–2020 normals)

Typical last frost April 10 (7 days earlier than the 30-year normal), typical first fall frost November 3 (7 days later). Frost-free season 207 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 Mechanicsville: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 2, 20% April 27, 30% April 22, 40% April 19, 50% April 17, 60% April 13, 70% April 9, 80% April 5, 90% March 31. Observed last spring frost in recent years: 2021 April 23, 2022 April 5, 2023 April 12, 2024 March 31, 2025 April 10, 2026 April 22.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1May 2Apr 17Mar 312021: April 232022: April 52023: April 122024: March 312025: April 102026: April 22Fall at Mechanicsville: chance of a frost before this dateFall, chance of a frost before the date: 10% October 12, 20% October 17, 30% October 20, 40% October 24, 50% October 27, 60% October 31, 70% November 1, 80% November 4, 90% November 9. Observed first fall frost in recent years: 2021 November 5, 2022 November 14, 2023 November 2, 2024 November 13, 2025 November 3.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Oct 12Oct 27Nov 92021: November 52022: November 142023: November 22024: November 132025: November 3
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 23November 5
2022April 5November 14
2023April 12November 2
2024March 31November 13
2025April 10November 3
2026April 22season not over yet

What these dates mean

The 195 days between the 50% dates in Mechanicsville bracket the span in which a light frost (32 °F) is equally likely to have occurred or not. The 50% dates are April 17 in spring and October 27 in fall; they are reference points, not frost dates, based on 29 years of NOAA records.

The cautious spring date for setting out tender crops is May 2, when there is only a 10 % chance of a light frost later. In fall, the cautious date to finish harvesting tender crops is October 12, when there is only a 10 % chance of a light frost earlier. A hard frost (28 °F) is more damaging than a light frost, and its median dates are April 2 in spring and November 6 in fall, indicating when a hard freeze becomes a 50 % chance.

How to read the probabilities

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

  • Spring: "10% after May 2" 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 12" 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 Mechanicsville, MDNumbered nearest stations: 1 — near Lexington Park, MD — 21 mi; 2 — near Arlington, VA — 30 mi; 3 — near Bladensburg, MD — 32 mi; 4 — Royal Oak, MD — 33 mi; 5 — Warsaw, VA — 35 mi.VADE25 mi · 40 km1. near Lexington Park, MD — 21 mi12. near Arlington, VA — 30 mi23. near Bladensburg, MD — 32 mi34. Royal Oak, MD — 33 mi45. Warsaw, VA — 35 mi5
  1. near Lexington Park, MD 21 mi (34 km)
  2. near Arlington, VA 30 mi (48 km)
  3. near Bladensburg, MD 32 mi (51 km)
  4. Royal Oak, MD 33 mi (53 km)
  5. Warsaw, VA 35 mi (56 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: 38.4928, -76.7258.