U.S. Frost Dates by Weather Station

NOAA station USC00046730 · California

Frost Dates for Paso Robles, CA

NOAA weather station Paso Robles (USC00046730), California · elevation 730 ft (223 m) · hardiness zone 9a*

  • Lower-risk planting dateafter April 13only 1 spring in 10 still has a frost later
  • Typical last frostMarch 1550% chance of a frost after it
  • Typical first fall frostNovember 1050% chance of a frost before it
  • Frost-free season238 daystypical year, 32°F
  • Hardiness zone9acalculated*

The year at a glance

Frost season at Paso Robles, CASpring: a frost after February 12 in 9 years out of 10, after March 15 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 10 in half of the years, before November 29 in 9 years out of 10. Typical frost-free season: 238 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 15First frost ~Nov 10Frost season at Paso Robles, CASpring: a frost after February 12 in 9 years out of 10, after March 15 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 10 in half of the years, before November 29 in 9 years out of 10. Typical frost-free season: 238 days.JFMAMJJASONDLast frost ~Mar 15First frost ~Nov 10
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 13October 23
50% (typical)March 15November 10
90% (likely)February 12November 29
Frost-free season (32°F, 50% chance)
238 days
Hard frost (28°F), last in spring, 50% chance after
February 9
Hard frost (28°F), first in fall, 50% chance before
November 26

The last 15 years (2006–2020 normals)

Typical last frost March 15 (same as the 30-year normal), typical first fall frost November 11 (1 day later). Frost-free season 238 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 Paso Robles: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 13, 20% April 6, 30% March 31, 40% March 25, 50% March 15, 60% March 8, 70% February 28, 80% February 24, 90% February 12. Observed last spring frost in recent years: 2021 March 18, 2022 March 13, 2023 March 8, 2024 April 7, 2025 March 11, 2026 February 22.Spring: last frostChance of a frost after this date10%50%90%Feb 1Mar 1Apr 1Apr 13Mar 15Feb 122021: March 182022: March 132023: March 82024: April 72025: March 112026: February 22Fall at Paso Robles: chance of a frost before this dateFall, chance of a frost before the date: 10% October 23, 20% October 30, 30% November 1, 40% November 5, 50% November 10, 60% November 14, 70% November 18, 80% November 22, 90% November 29. Observed first fall frost in recent years: 2021 November 23, 2022 November 3, 2023 October 29, 2024 November 7, 2025 November 30.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Oct 23Nov 10Nov 292021: November 232022: November 32023: October 292024: November 72025: November 30
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
2021March 18November 23
2022March 13November 3
2023March 8October 29
2024April 7November 7
2025March 11November 30
2026February 22season not over yet

What these dates mean

Setting out tender crops on the early spring date of February 12 in Paso Robles carries a 90 % chance of a frost later that season, making it a gamble for gardeners. A cautious schedule would wait until the later spring date of April 13, which has only a 10 % chance of a frost thereafter.

The 50 % spring date of March 15 indicates an even-odds chance of a frost later than that day, while the 50 % fall date of November 10 signals an even-odds chance of a frost earlier than that day. For a careful plan, tender crops are typically finished by the fall cautious date of October 23, which only has a 10 % chance that a frost has arrived earlier.

Hard frost at 28 °F, marked by the median dates February 9 and November 26, can injure plants more severely than the 32 °F light-frost thresholds.

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 Paso Robles, CANumbered nearest stations: 1 — Paso Robles (Airport), CA — 4 mi; 2 — King City, CA — 47 mi; 3 — near Corcoran, CA — 70 mi; 4 — Auberry, CA — 120 mi; 5 — Sandberg, CA — 126 mi.50 mi · 80 km1. Paso Robles (Airport), CA — 4 mi12. King City, CA — 47 mi23. near Corcoran, CA — 70 mi34. Auberry, CA — 120 mi45. Sandberg, CA — 126 mi5
  1. Paso Robles (Airport), CA 4 mi (7 km)
  2. King City, CA 47 mi (76 km)
  3. near Corcoran, CA 70 mi (112 km)
  4. Auberry, CA 120 mi (194 km)
  5. Sandberg, CA 126 mi (204 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: 35.6278, -120.6856.