U.S. Frost Dates by Weather Station

NOAA station USW00024235 · Oregon

Frost Dates for Sexton Summit, OR

NOAA weather station Sexton Summit (USW00024235), Oregon · elevation 3832 ft (1168 m) · hardiness zone 8b*

  • Lower-risk planting dateafter June 7only 1 spring in 10 still has a frost later
  • Typical last frostMay 1650% chance of a frost after it
  • Typical first fall frostOctober 3050% chance of a frost before it
  • Frost-free season164 daystypical year, 32°F
  • Hardiness zone8bcalculated*

The year at a glance

Frost season at Sexton Summit, ORSpring: a frost after April 23 in 9 years out of 10, after May 16 in half of the years, after June 7 in 1 year out of 10. Fall: the first frost comes before October 8 in 1 year out of 10, before October 30 in half of the years, before November 17 in 9 years out of 10. Typical frost-free season: 164 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~May 16First frost ~Oct 30Frost season at Sexton Summit, ORSpring: a frost after April 23 in 9 years out of 10, after May 16 in half of the years, after June 7 in 1 year out of 10. Fall: the first frost comes before October 8 in 1 year out of 10, before October 30 in half of the years, before November 17 in 9 years out of 10. Typical frost-free season: 164 days.JFMAMJJASONDLast frost ~May 16First frost ~Oct 30
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 26 years of NOAA records (1991–2020 normals)
ChanceLast frost in spring afterFirst frost in fall before
10% (unlikely)June 7October 8
50% (typical)May 16October 30
90% (likely)April 23November 17
Frost-free season (32°F, 50% chance)
164 days
Hard frost (28°F), last in spring, 50% chance after
April 23
Hard frost (28°F), first in fall, 50% chance before
November 17

The last 15 years (2006–2020 normals)

Typical last frost May 10 (6 days earlier than the 30-year normal), typical first fall frost November 1 (2 days later). Frost-free season 171 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 Sexton Summit: chance of a frost after this dateSpring, chance of a frost after the date: 10% June 7, 20% June 1, 30% May 27, 40% May 22, 50% May 16, 60% May 10, 70% May 2, 80% April 29, 90% April 23. Observed last spring frost in recent years: 2021 May 20, 2022 May 30, 2023 May 8, 2025 May 4.Spring: last frostChance of a frost after this date10%50%90%May 1Jun 1Jun 7May 16Apr 232021: May 202022: May 302023: May 82025: May 4Fall at Sexton Summit: chance of a frost before this dateFall, chance of a frost before the date: 10% October 8, 20% October 15, 30% October 21, 40% October 25, 50% October 30, 60% November 2, 70% November 5, 80% November 9, 90% November 17. Observed first fall frost in recent years: 2021 October 11, 2022 November 1, 2023 October 25.Fall: first frostChance of a frost before this date10%50%90%Oct 1Nov 1Dec 1Oct 8Oct 30Nov 172021: October 112022: November 12023: October 25
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 20October 11
2022May 30November 1
2023May 8October 25
2024incomplete recordincomplete record
2025May 4incomplete record
2026incomplete recordseason not over yet

What these dates mean

The 164 days between the 50% dates in Sexton Summit bracket the period when most tender crops can be grown.

May 16 is the spring 50% date, indicating an even chance of a light frost later than this date. October 30 is the fall 50% date, indicating an even chance of a light frost earlier than this date. The cautious spring date for setting out tender crops is June 7, when only a 10% chance of a later light frost remains. The cautious fall date for finishing tender crops is October 8, when only a 10% chance of an earlier light frost remains. Hard-frost 50% dates fall on April 23 in spring and November 17 in fall.

A hard frost at 28 °F can injure plants that survive a light frost at 32 °F, 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 June 7" 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 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 Sexton Summit, ORNumbered nearest stations: 1 — Riddle, OR — 24 mi; 2 — near Medford, OR — 29 mi; 3 — near Shady Cove, OR — 35 mi; 4 — near Roseburg, OR — 42 mi; 5 — Prospect, OR — 44 mi.CA25 mi · 40 km1. Riddle, OR — 24 mi12. near Medford, OR — 29 mi23. near Shady Cove, OR — 35 mi34. near Roseburg, OR — 42 mi45. Prospect, OR — 44 mi5
  1. Riddle, OR 24 mi (39 km)
  2. near Medford, OR 29 mi (47 km)
  3. near Shady Cove, OR 35 mi (57 km)
  4. near Roseburg, OR 42 mi (68 km)
  5. Prospect, OR 44 mi (71 km)

Sources

* Hardiness zone 8b: zone derived from PRISM 2023 grid at the station location (not the official USDA map). Source data: PRISM Group, Oregon State University.

Station coordinates: 42.6003, -123.3642.