U.S. Frost Dates by Weather Station

NOAA station USC00041697 · California

Frost Dates for Cherry Valley Dam, CA

NOAA weather station Cherry Valley Dam (USC00041697), California · elevation 4765 ft (1452 m) · hardiness zone 8a*

  • Lower-risk planting dateafter May 29only 1 spring in 10 still has a frost later
  • Typical last frostMay 250% chance of a frost after it
  • Typical first fall frostNovember 450% chance of a frost before it
  • Frost-free season183 daystypical year, 32°F
  • Hardiness zone8acalculated*

The year at a glance

Frost season at Cherry Valley Dam, CASpring: a frost after April 14 in 9 years out of 10, after May 2 in half of the years, after May 29 in 1 year out of 10. Fall: the first frost comes before October 15 in 1 year out of 10, before November 4 in half of the years, before November 22 in 9 years out of 10. Typical frost-free season: 183 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 2First frost ~Nov 4Frost season at Cherry Valley Dam, CASpring: a frost after April 14 in 9 years out of 10, after May 2 in half of the years, after May 29 in 1 year out of 10. Fall: the first frost comes before October 15 in 1 year out of 10, before November 4 in half of the years, before November 22 in 9 years out of 10. Typical frost-free season: 183 days.JFMAMJJASONDLast frost ~May 2First 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.

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 29October 15
50% (typical)May 2November 4
90% (likely)April 14November 22
Frost-free season (32°F, 50% chance)
183 days
Hard frost (28°F), last in spring, 50% chance after
April 16
Hard frost (28°F), first in fall, 50% chance before
November 20

The last 15 years (2006–2020 normals)

Typical last frost May 2 (same as the 30-year normal), typical first fall frost November 5 (1 day later). Frost-free season 185 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 Cherry Valley Dam: chance of a frost after this dateSpring, chance of a frost after the date: 10% May 29, 20% May 20, 30% May 13, 40% May 8, 50% May 2, 60% April 28, 70% April 24, 80% April 19, 90% April 14. Observed last spring frost in recent years: 2021 May 21, 2025 April 27, 2026 April 24.Spring: last frostChance of a frost after this date10%50%90%Apr 1May 1Jun 1May 29May 2Apr 142021: May 212025: April 272026: April 24Fall at Cherry Valley Dam: chance of a frost before this dateFall, chance of a frost before the date: 10% October 15, 20% October 22, 30% October 28, 40% November 1, 50% November 4, 60% November 8, 70% November 11, 80% November 15, 90% November 22. Observed first fall frost in recent years: 2021 October 18, 2025 October 14.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Dec 1Oct 15Nov 4Nov 222021: October 182025: October 14
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
2021May 21October 18
2022incomplete recordincomplete record
2023incomplete recordincomplete record
2024incomplete recordincomplete record
2025April 27October 14
2026April 24season not over yet

What these dates mean

The 183 days between the 50% dates in Cherry Valley Dam span the window from the median spring light-frost date of May 2 to the median fall light-frost date of November 4, each representing an even chance of a frost occurring. Gardeners can use these midsummer markers to gauge the balance of risk, knowing that a light frost is just as likely before or after either date.

For a cautious plan, tender crops are set out after the May 29 spring date, which carries only a 10 % chance of a later frost, while harvest or final planting should be completed before the October 15 fall date, which also has only a 10 % chance of an earlier frost. The 50% hard-frost dates are April 16 in spring and November 20 in fall; hard frost at 28 °F can injure plants that survive a 32 °F light frost, making it a more critical threshold.

How to read the probabilities

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

  • Spring: "10% after May 29" 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 15" 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 Cherry Valley Dam, CANumbered nearest stations: 1 — Sonora, CA — 26 mi; 2 — Calaveras Big Trees, CA — 30 mi; 3 — Lee Vining, CA — 43 mi; 4 — Auberry, CA — 65 mi; 5 — Minden, NV — 68 mi.NV50 mi · 80 km1. Sonora, CA — 26 mi12. Calaveras Big Trees, CA — 30 mi23. Lee Vining, CA — 43 mi34. Auberry, CA — 65 mi45. Minden, NV — 68 mi5
  1. Sonora, CA 26 mi (41 km)
  2. Calaveras Big Trees, CA 30 mi (48 km)
  3. Lee Vining, CA 43 mi (70 km)
  4. Auberry, CA 65 mi (104 km)
  5. Minden, NV 68 mi (110 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: 37.9747, -119.9161.