Ragweed season in Texas ends around November 29

Ragweed doesn't stop on a schedule. It keeps flowering until a freeze kills the plants, which is why the end of the season is a weather question rather than a calendar one — and in Texas, the answer sits around November 29 in a typical year.

Is ragweed season still going in Texas?

Status comes from the typical season window for this area, not from a pollen count — a cool spring or a late frost moves the real dates by a week or two either way. These are the windows for Texas.

Why the end of the season is a frost date

Two thresholds matter, and NOAA records both. The first 32°F frost is the one that ends ragweed season. The first 28°F hard freeze, which follows it, is what finishes off the plants for good. City tables on this site show both.

These are fifty-fifty dates, not deadlines. At each city's own weather station, NOAA's 30-year record puts half of the first freezes before the date and half after — so ragweed ends early in a cold autumn and hangs on well past the date in a warm one.

Many people plan ahead of the season; if that includes anything medical, ask your doctor.

Ragweed
The Texas ragweed season across the year, from early August. Ragweed's bar ends at the typical first frost — around November 29.

Where in Texas it ends first

Frost doesn't switch a state off all at once. It reaches the coldest corners of Texas around October 27 and the mildest around January 3 — 68 days apart, so ragweed season can be finished at one end of the state while it's still going at the other.

City First frost (32°F) Hard freeze (28°F)
Amarillo October 27 November 5
Lubbock November 2 November 11
Midland November 14 November 24
Waco November 15 November 28
El Paso November 20 December 1
Fort Worth November 24 December 6
Dallas November 29 December 12
Austin December 3 December 27
San Antonio December 3 December 23
Corpus Christi December 21 December 30
Houston December 28 January 8
Brownsville January 2 rarely reached
McAllen January 3 rarely reached

Based on 30 years of NOAA frost records (1991–2020).

What comes after

Once frost has been through, the pollen year starts over: Texas gets only a short break, and tree pollen opens the next one in early December.

The full Texas pollen year — tree, grass and ragweed, with the dates each one starts — is on the Texas season page. For how ragweed works nationally, see ragweed season.

Common questions

When does ragweed season end in Texas?

Around November 29 in a typical year — the day the first freeze usually arrives in Texas. A warm autumn pushes it later; an early cold snap ends it sooner.

Does the first frost really end it?

Effectively, yes — and that is what makes the date worth looking up. Common ragweed is an annual: it grows from seed every spring and has no way to survive a freeze, so the cold kills the plants outright rather than slowing them down. A dead plant releases no more pollen, which is why the first frost is an ending and not just a quiet spell.

Does it end everywhere in Texas at once?

No. The first freeze crosses Texas over roughly 68 days — earliest around October 27, latest around January 3 — so ragweed season is finished at one end of the state while it is still running at the other. The city table above gives the local date.

What comes after ragweed in Texas?

Nothing, for a while — ragweed is the last pollen of the year. The next season to open in Texas is tree pollen in early December, usually starting with mountain cedar (Ashe juniper).

Sources: NOAA U.S. Climate Normals, 1991–2020 (first-frost and hard-freeze dates) · Asthma and Allergy Foundation of America · Iowa State University Extension — common ragweed. Season windows reviewed August 2026.