U.S. Frost Dates by Weather Station

NOAA station USC00410832 · Texas

Frost Dates for Blanco, TX

NOAA weather station Blanco (USC00410832), Texas · elevation 1310 ft (399 m) · hardiness zone 8b*

  • Lower-risk planting dateafter April 8only 1 spring in 10 still has a frost later
  • Typical last frostMarch 2050% chance of a frost after it
  • Typical first fall frostNovember 1050% chance of a frost before it
  • Frost-free season236 daystypical year, 32°F
  • Hardiness zone8bcalculated*

The year at a glance

Frost season at Blanco, TXSpring: a frost after February 28 in 9 years out of 10, after March 20 in half of the years, after April 8 in 1 year out of 10. Fall: the first frost comes before October 27 in 1 year out of 10, before November 10 in half of the years, before December 2 in 9 years out of 10. Typical frost-free season: 236 days.JanFebMarAprMayJunJulAugSepOctNovDecLast frost ~Mar 20First frost ~Nov 10Frost season at Blanco, TXSpring: a frost after February 28 in 9 years out of 10, after March 20 in half of the years, after April 8 in 1 year out of 10. Fall: the first frost comes before October 27 in 1 year out of 10, before November 10 in half of the years, before December 2 in 9 years out of 10. Typical frost-free season: 236 days.JFMAMJJASONDLast frost ~Mar 20First 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 8October 27
50% (typical)March 20November 10
90% (likely)February 28December 2
Frost-free season (32°F, 50% chance)
236 days
Hard frost (28°F), last in spring, 50% chance after
March 6
Hard frost (28°F), first in fall, 50% chance before
November 23

The last 15 years (2006–2020 normals)

Typical last frost March 20 (same as the 30-year normal), typical first fall frost November 10. Frost-free season 234 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 Blanco: chance of a frost after this dateSpring, chance of a frost after the date: 10% April 8, 20% April 2, 30% March 30, 40% March 25, 50% March 20, 60% March 16, 70% March 11, 80% March 5, 90% February 28.Spring: last frostChance of a frost after this date10%50%90%Mar 1Apr 1Apr 8Mar 20Feb 28Fall at Blanco: chance of a frost before this dateFall, chance of a frost before the date: 10% October 27, 20% November 1, 30% November 3, 40% November 6, 50% November 10, 60% November 14, 70% November 19, 80% November 25, 90% December 2.Fall: first frostChance of a frost before this date10%50%90%Nov 1Dec 1Oct 27Nov 10Dec 2
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.

What these dates mean

Setting out tender crops on February 28 in Blanco carries a 90 % chance of a frost later that season, making it a gamble. The cautious spring date for tender crops is April 8, which has a 10 % chance of a frost later than this date, and the risky early date is February 28.

The 50% light-frost date is March 20, which carries a 50 % chance of a frost later than this date, and the 50% autumn date is November 10, which carries a 50 % chance of a frost earlier than this date. The 50% hard-frost dates are March 6 and November 23.

For a cautious plan, tender crops should be finished by October 27, the 10 % chance date for early-fall frost. A hard frost at 28 °F can damage plant tissue that survives a light frost at 32 °F.

How to read the probabilities

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

  • Spring: "10% after April 8" 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 27" 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 Blanco, TXNumbered nearest stations: 1 — near Canyon Lake, TX — 21 mi; 2 — Dripping Springs, TX — 27 mi; 3 — Boerne, TX — 28 mi; 4 — Fredericksburg, TX — 31 mi; 5 — San Marcos, TX — 31 mi.25 mi · 40 km1. near Canyon Lake, TX — 21 mi12. Dripping Springs, TX — 27 mi23. Boerne, TX — 28 mi34. Fredericksburg, TX — 31 mi45. San Marcos, TX — 31 mi5
  1. near Canyon Lake, TX 21 mi (33 km)
  2. Dripping Springs, TX 27 mi (43 km)
  3. Boerne, TX 28 mi (45 km)
  4. Fredericksburg, TX 31 mi (50 km)
  5. San Marcos, TX 31 mi (51 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: 30.095, -98.4142.