Alton, IL Pollen Count

Alton, IL · Last updated Friday, November 6, 2026

This page shows the most recent reading available for Alton — from Friday, November 6, 2026 (1 day ago) — not today's reading.

Pollen Overview

Today's overall pollen level and the dominant type (trees, weeds, grass, or mold).

LowDominant Allergen: Weeds
Alton, IL · Sat, Nov 7

Total Pollen Index

The combined pollen level across all types (0–100).

Alton, IL

22index / 100
Low
0–40 Low41–60 Moderate61–100 High

Weeds Index

How active weeds pollen is today (0–100).

Alton, IL

28index / 100
Low
0–40 Low41–60 Moderate61–100 High

Pollen Types

Pick a pollen subtype to update the species forecast

Top Allergens for Alton:

5-Day Alton Overall Pollen Forecast

Bars are colored by severity (Low/Moderate/High).

Pollen count Alton residents check each morning

The Alton pollen count today is 22 (Low). The main driver is Ragweed, with weed pollen at 28 today. Weed pollen leads the split at 28 (Low on its own scale), followed by grass pollen at 2 and tree pollen at 0.6. Below, the plant detail and the multi-day outlook show whether today is the pattern or the exception. Pollen Atlas updated this count on Friday, November 6, 2026.

A Low band on the Pollen Atlas index means the Total Pollen Index has stayed in the lower part of the 0–100 scale. Readings in this band are built from low individual category values rather than from one large spike, and the category split above matters more than the headline number: a low total can still contain one category, such as weed pollen or mold, reading noticeably higher than the rest, which is why the split is printed on every Alton page.

Fall is ragweed season across most of the United States: ragweed plants release pollen from late summer into autumn, and weed pollen is typically the last major outdoor pollen category to fade as the weather cools. That pattern is why an autumn total is so often weed-led even when the headline number is low — tree and grass pollen have usually receded by then, leaving weed pollen, and on damp days mold, to make up most of what the index records. In the Plains and around the Great Lakes, ragweed is a familiar late-season plant of open ground, field edges and disturbed soil, which is why it so often leads inland autumn readings.

To see whether today’s pollen level holds, check the 5-day Alton pollen forecast below — it is currently holding, with Friday the highest day in the window.

This is the pollen count Alton residents check each morning, built from the day’s tree, grass, weed and mold readings.

What is the Alton pollen count today?

The Alton pollen count today is 22 out of 100 (Low) on the Pollen Atlas Total Pollen Index, driven mainly by Ragweed.

Short answer for anyone searching pollen count today Alton: this page is updated every morning with the day’s modelled reading.

Alton allergies today

Alton allergies today are set by the same reading as the pollen count above: the Total Pollen Index is 22 (Low), driven mainly by Ragweed. When people ask about Alton allergies, this is the number that answers them — one daily index built from today’s tree, grass, weed and mold readings for Alton.

Allergies in Alton follow the Illinois calendar set out below — the chapters, the plants behind them, and the 5-day forecast on this page show whether today is typical for the season or an exception to it. If you are checking allergies today in Alton before heading outdoors, the split at the top of this page is the part to read: it shows which pollen is doing the work today, not just how high the total sits.

Read the five-day table on this page as the Alton allergy forecast: today reads 22 (Low), and the day-by-day outlook shows whether Alton allergies are set to ease or build across the week — the days to plan outdoor time around are the ones where the index steps down, not just today.

In practice, the allergy count Alton today records is this same combined reading — tree, grass, weed and mold in one index.

The Alton allergy count today is 22 (Low) — the same Total Pollen Index as the pollen count above, in one combined reading.

Pollen count today Alton: the 5-day forecast

DayTotal Pollen IndexBand
Friday, November 622Low
Saturday, November 722Low
Sunday, November 822Low
Monday, November 922Low
Tuesday, November 1021Low

Pollen Atlas forecasts Alton’s pollen count to peak on Friday at 22 (Low) over the next 5 days.

Pollen by type in Alton

What is driving Alton’s pollen today

The shape of today’s 22 (Low) is set by weed pollen at 28 (Low on its own scale) — about 92% of the four category readings added together, 26 points clear of the next category, grass pollen at 2. A weed-led total is the classic late-year shape: tree and grass pollen have usually receded, leaving weed pollen — and on damp days mold — to make up most of what the index records. Weed pollen leading in November runs against the usual calendar — the Illinois weed chapter runs August to October — so today’s lead is the model outranking the pattern, and this page reports the modelled reading first.

Plant-level detail is not in today’s feed for Alton, so the drivers have to be read from the category split above. The Illinois guide’s account of Illinois names the classic tree, grass and ragweed sequence at full strength, with mold as a Chicago co-headliner — the pollens behind readings of this shape in this state — and the split shows how much of today’s total each category is actually carrying.

Across the five-day window the Total Pollen Index runs from 21 to 22, never changing band. Today’s 22 sits 0 points above the window’s average of 21.8 — a steady window, in which one day reads much like the next.

Plants affecting Alton now

Detailed plant-by-plant readings for Alton were not returned in today\u2019s source data, so this section summarises the pollen types the index above is built from instead of listing individual plants.

Tree pollen is one of the categories with a non-zero reading today, at 0.6 (Low).

Grass pollen is one of the categories with a non-zero reading today, at 2 (Low).

Weed pollen is one of the categories with a non-zero reading today, at 28 (Low).

In the Midwest & Great Lakes pattern, the plants that typically shape this city’s year are spring trees, late-spring and summer grasses, and late-summer and autumn ragweed — named here as regional context only, not as today\u2019s measurements.

Plant detail returns here automatically on any day the source data includes it.

Every pollen type, with photos and seasons: the pollen directory.

Alton pollen through the year

Three chapters make the Illinois pollen year, and Alton follows them in the Midwest & Great Lakes order. The tree chapter: trees run from March into May, later near the big lakes. The grass chapter: grasses hold from May through July. The weed chapter: ragweed builds from mid-August, peaks in September, and ends at the first frost. Mold builds through the humid summer and fills the gaps between chapters.

Lake Michigan delays spring flowering near the shore, so downstate Illinois often runs two to three weeks ahead of Chicago in spring — and behind it at the fall frost. The season typically starts in March in the south of the state and April in the Chicago area. The Illinois guide singles out the classic tree, grass and ragweed sequence at full strength, with mold as a Chicago co-headliner.

November falls between the main chapters of the Illinois pollen year — the tail of one and the approach of the next — so the calendar alone explains little today, and the modelled split above carries the story. Between them, the three chapters cover 8 months of the Illinois year, March to October — a compressed season, which is why its chapters arrive in quick succession. The full calendar is set out in the Illinois allergy season guide.

How to read this index

Pollen Atlas reports the Alton pollen count on a Total Pollen Index from 0 to 100, built from separate tree, grass and weed readings. The total is a summary, not an average of the three: a single strong category can lift it, and three quiet categories can hold it down even in a month when Alton, IL pollen is usually more active. Index values are a modelled pollen risk index computed by Pollen Atlas from open weather, vegetation and phenology data, calibrated against CDC/NAB season data, with plant detail by the Google Pollen API. The index is a modelled 0–100 scale, not a measured count, and figures update through the day, so a morning and an evening visit to this page can legitimately show different numbers.

Alton in today’s national picture

At 22 (Low), Alton ranks joint 44134th of the 90896 cities Pollen Atlas tracks today — in the middle of the national table. The highest reading in the country today is Serpa, Portugal at 53, and the lowest is Galiakberovo, Russia at 5. The whole table spans 48 points today — a wide-open day, when the top and bottom of the table are effectively in different seasons.

Around Alton: East Alton, IL (3 miles away) reads 23 (Low); West Alton, MO (4 miles away) reads 22 (Low); Rosewood Heights, IL (4 miles away) reads 23 (Low). Alton reads 1 point lower than its nearest tracked neighbour today. Across Illinois’s 1456 tracked cities, today runs from 14 in Hamburg to 41 in Elburn.

Pollen totals are population numbers; symptoms are personal. The same reading can leave one Alton resident untouched and floor another, depending on which pollens they are sensitised to. If this pattern finds you every season, allergists in Alton, IL can test whether tree, grass, weed or mold is the category that matters for you — the four readings at the top of this page are the starting point for that conversation.

Alton in its local area

Alton is a city in Madison County, Illinois. Its population is 25,430 (ACS 2023).

Across Illinois’s 1456 tracked cities, Alton ranks joint 1155th today.

Like every Pollen Atlas city page, the Alton, IL pollen count is refreshed each morning.

Nearby cities

From Pollen Atlas News

See how Alton ranks in today's pollen count rankings — the worst cities for allergies today

See Alton on the US pollen map

Search the full allergist directory

Pollen indexes: a modelled pollen risk index computed by Pollen Atlas from open weather, vegetation and phenology data, calibrated against CDC/NAB season data. Plant detail: Google Pollen API. Index values are modelled, not measured counts. Sources: CDC/NAB; USA-NPN; GBIF (CC BY); ESA WorldCover (CC BY 4.0).