Collinsville, Illinois Pollen Count
Collinsville pollen count and allergy forecast — tree, grass, and ragweed seasons and what’s pollinating now
Collinsville, IL · Pollen season
In June, grass pollen is in season in Collinsville — the dominant allergen you're likely reacting to right now.
Based on the seasonal pollen calendar for this region.
Pollen by type this season
- TreeOut of season
- GrassIn season
- Weed / RagweedOut of season
Collinsville pollen calendar
Typical peak months for each pollen type in this climate region. The highlighted column is the current month.
How Collinsville’s pollen count works
The calendar above is tuned to Collinsville’s warm, humid subtropical Southeast climate, not a national average: tree pollen peaks Feb–Apr, grass Apr–Sep, and ragweed Aug–Nov here. Those windows are why grass pollen is the one in season in Collinsville right now.
No live count is wired up for Collinsville today, so the seasonal calendar above is your guide to which allergen is in season. Counts run highest on warm, dry, windy mornings and drop after rain, which washes pollen out of the air — reported on the None / Low / Moderate / High / Very High scale.
Frequently asked
- When is pollen worst in Collinsville?
- The late-summer ragweed run is the headline in Collinsville: 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 pollen is what's driving counts this month.
- What's in the air in Collinsville right now?
- In June, grass pollen is in season in Collinsville — the dominant allergen you're likely reacting to right now. A live count, when available, confirms the day's actual reading; this reflects the typical peak windows for Collinsville's warm, humid subtropical Southeast climate.
- Is tree or grass pollen higher in Collinsville in spring?
- In spring, tree pollen leads in Collinsville — 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 Collinsville's pollen season distinctive?
- Collinsville 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 Collinsville?
- Through Collinsville'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.
- What pollen index counts as high?
- Pollen is reported on a categorical scale — None, Low, Moderate, High, and Very High. "High" and above means most allergy sufferers notice symptoms even with brief outdoor exposure, and sensitized people should limit time outside and pre-medicate. "Low" to "Moderate" usually only affects highly sensitive individuals.
More for Collinsville
See the full Collinsville, IL weather forecast — hour-by-hour outlook, NOAA radar, satellite, and air quality.
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