Rock Hill, South Carolina Pollen Count & Allergy Forecast

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

Rock Hill, SC · Pollen season

In September, grass and ragweed pollen are in season in Rock Hill — grass peaks Apr–Sep and ragweed peaks Aug–Nov.

Based on the seasonal pollen calendar for this region.

Rock Hill on the WeatherStory Allergy Index

Rock Hill isn't one of the 100 metros on the WeatherStory Allergy Index, but the nearest ranked metro — Charlotte, NC, about 21 miles away — sits at #14 with a 304-day combined pollen season.

#14of 100nearest ranked metro
Load index
42
Combined season
304 days
Heaviest load
Grass · 183 days
Nearest ranked metro
Charlotte, NC · ~21 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 Rock Hill in September, at an estimated High level.

Pollen by type this season

What pollinates near Rock Hill

The tree, grass, and weed species that drive Rock Hill’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.

Rock Hill’s allergy year

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

JFMAMJJASOND
TreeFeb–Apr
GrassApr–Sep
RagweedAug–Nov

How Rock Hill compares to the U.S. average

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

Tree~4 wks earlier
Grass~4 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 Rock Hill’s pollen count works

The calendar above is tuned to Rock Hill’s warm, humid subtropical Southeast climate, not a national average: tree pollen runs from week 5 (early February) to week 17 (late April), grass from week 14 (early April) to week 39 (late September), and ragweed from week 31 (early August) to week 48 (late November) here — a 304-day combined pollen season. Those windows are why grass and ragweed pollen are in season in Rock Hill right now.

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

For the science behind Rock Hill’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 Rock Hill?
The late-summer ragweed run is the headline in Rock Hill: weed pollen peaks Aug–Nov, the longest and most punishing window of the year here. Tree pollen comes first (Feb–Apr) and grass bridges the gap (Apr–Sep), but it's the ragweed stretch that floors most sufferers. Currently, grass and ragweed pollen are in season.
What's in the air in Rock Hill right now?
In September, grass and ragweed pollen are in season in Rock Hill — grass peaks Apr–Sep and ragweed peaks Aug–Nov. On Rock Hill'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 Rock Hill in spring?
In spring, tree pollen leads in Rock Hill — trees pollinate Feb–Apr, ahead of grass (Apr–Sep). 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 Rock Hill's pollen season distinctive?
Rock Hill 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 Rock Hill?
Through Rock Hill's peak windows (tree Feb–Apr, grass Apr–Sep, 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 Rock Hill?
Tree pollen is next in Rock Hill: it opens around week 5 (early February), peaks around week 11, and runs about 91 days.
What is the allergy forecast in Rock Hill today?
With no live reading for Rock Hill today, its allergy forecast is the seasonal estimate above: a typical September level of High, led by ragweed pollen.