Brownsville, Texas Pollen Count & Allergy Forecast

Brownsville pollen count and allergy forecast — tree, grass, and ragweed seasons and what’s pollinating now

Brownsville, TX · Pollen season

In September, ragweed pollen is in season in Brownsville, peaking Aug–Nov.

Based on the seasonal pollen calendar for this region.

Brownsville on the WeatherStory Allergy Index

Brownsville isn't one of the 100 metros on the WeatherStory Allergy Index, but the nearest ranked metro — McAllen, TX, about 51 miles away — sits at #19 with a 335-day combined pollen season.

#19of 100nearest ranked metro
Load index
42
Combined season
335 days
Heaviest load
Grass · 183 days
Nearest ranked metro
McAllen, TX · ~51 mi

See the full 100 worst U.S. cities for pollen — a modeled seasonal load ranking (see methodology).

Typical now — Septemberseasonal estimate, not a live reading

Ragweed pollen typically leads in Brownsville in September, at an estimated High level.

Pollen by type this season

What pollinates near Brownsville

The tree, grass, and weed species that drive Brownsville’s pollen seasons, with each plant’s typical peak.

Trees

  • Oak Quercuspeaks March–April
  • Loblolly pine Pinus taedapeaks March–April
  • Pecan Carya illinoinensispeaks April–May
  • Sweetgum Liquidambar styracifluapeaks March–April
  • Mulberry Moruspeaks March–April
  • Elm Ulmuspeaks February–March

Grasses

  • Bermuda grass Cynodon dactylonpeaks May–September
  • Bahia grass Paspalum notatumpeaks May–September
  • Johnson grass Sorghum halepensepeaks June–August
  • Timothy Phleum pratensepeaks May–June

Weeds

  • Common ragweed Ambrosia artemisiifoliapeaks August–October
  • Giant ragweed Ambrosia trifidapeaks August–October
  • Pigweed Amaranthuspeaks August–September
  • English plantain Plantago lanceolatapeaks May–September

Species are the region’s common wind-pollinated plants; peak months are a seasonal estimate, not a measured count — see methodology.

Brownsville’s allergy year

Typical month-by-month pollen intensity for Brownsville, tuned to its latitude and climate region — darker means higher typical counts. The highlighted column is the current month.

JFMAMJJASOND
TreeJan–Mar
GrassMar–Aug
RagweedAug–Nov

How Brownsville compares to the U.S. average

Each colored bar is Brownsville’s typical season against the national-average window (grey). The offset is the per-city timing shift.

Tree~9 wks earlier
Grass~9 wks earlier
Ragweedabout average

“U.S. average” is the textbook tree Mar–May, grass May–Jul, ragweed Aug–Oct calendar. The shift is a phenology estimate (Hopkins’ bioclimatic law), not a measured count — see methodology.

How Brownsville’s pollen count works

The calendar above is tuned to Brownsville’s warm, humid subtropical Southeast climate, not a national average: tree pollen runs from week 1 (early January) to week 13 (late March), grass from week 10 (early March) to week 35 (late August), and ragweed from week 31 (early August) to week 48 (late November) here — a 335-day combined pollen season. Those windows are why ragweed pollen is the one in season in Brownsville right now.

No live count is wired up for Brownsville today, so the seasonal calendar above is your guide to which allergen is in season.

For the science behind Brownsville’s pollen seasons — how counts are measured, when each type peaks, and what the numbers mean — see the pollen count scale and the other pollen & allergy guides.

Frequently asked

When is pollen worst in Brownsville?
The late-summer ragweed run is the headline in Brownsville: weed pollen peaks Aug–Nov, the longest and most punishing window of the year here. Tree pollen comes first (Jan–Mar) and grass bridges the gap (Mar–Aug), but it's the ragweed stretch that floors most sufferers. Currently, ragweed pollen is in season.
What's in the air in Brownsville right now?
In September, ragweed pollen is in season in Brownsville, peaking Aug–Nov. On Brownsville's warm, humid subtropical Southeast calendar the typical September level is High, led by ragweed pollen — a seasonal estimate, not a live count.
Is tree or grass pollen higher in Brownsville in spring?
In spring, tree pollen leads in Brownsville — trees pollinate Jan–Mar, ahead of grass (Mar–Aug). The handoff is the tail of the tree window: tree counts taper as grass climbs, so an early-spring flare is more likely tree pollen and a late-spring one more likely grass.
What makes Brownsville's pollen season distinctive?
Brownsville sits in the warm, humid subtropical Southeast zone, which means an unusually long, overlapping season — the warm climate stretches grass across much of the year and pushes ragweed deep into autumn. That shapes when symptoms hit and which allergen to watch.
How do I reduce pollen exposure in Brownsville?
Through Brownsville's peak windows (tree Jan–Mar, grass Mar–Aug, ragweed Aug–Nov), keep windows shut and run AC on recirculate; counts run highest on dry, warm, windy mornings, so push outdoor activity to late afternoon or just after rain, which clears pollen from the air. A HEPA purifier indoors, a saline rinse after being outside, showering before bed, and starting antihistamines a week or two before your worst local window all measurably cut symptoms.
When does the next pollen season start in Brownsville?
Tree pollen is next in Brownsville: it opens around week 1 (early January), peaks around week 7, and runs about 91 days.
What is the allergy forecast in Brownsville today?
With no live reading for Brownsville today, its allergy forecast is the seasonal estimate above: a typical September level of High, led by ragweed pollen.