Harrow, United Kingdom Pollen Count Today
Harrow, United Kingdom · Updated Saturday, November 7, 2026
Pollen Overview
Today's overall pollen level and the dominant type (trees, weeds, grass, or mold).
Total Pollen Index
The combined pollen level across all types (0–100).
Harrow, United Kingdom
Weeds Index
How active weeds pollen is today (0–100).
Harrow, United Kingdom
Pollen Types
Pick a pollen subtype to update the species forecast
5-Day Harrow Overall Pollen Forecast
Bars are colored by severity (Low/Moderate/High).
This reading is the forecast point shared with Greenhill, United Kingdom — 2 nearby places use the same point; Harrow is 0.6 km from it.
Pollen count Harrow residents check each morning
The Harrow pollen count today is 32 (Low). The main driver is Ragweed, with weed pollen at 37 today. Weed pollen leads the split at 37 (Low on its own scale), followed by tree pollen at 34 and grass 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 Saturday, November 7, 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 Harrow 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.
To see whether today’s pollen level holds, check the 5-day Harrow pollen forecast below — it is currently mixed, with Monday the highest day in the window.
This is the pollen count Harrow residents check each morning, built from the day’s tree, grass, weed and mold readings.
What is the Harrow pollen count today?
The Harrow pollen count today is 32 out of 100 (Low) on the Pollen Atlas Total Pollen Index, driven mainly by Ragweed.
Short answer for anyone searching pollen count today Harrow: this page is updated every morning with the day’s modelled reading.
Harrow allergies today
Harrow allergies today are set by the same reading as the pollen count above: the Total Pollen Index is 32 (Low), driven mainly by Ragweed. When people ask about Harrow allergies, this is the number that answers them — one daily index built from today’s tree, grass, weed and mold readings for Harrow.
Allergies in Harrow follow the United Kingdom 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 Harrow 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 Harrow allergy forecast: today reads 32 (Low), and the day-by-day outlook shows whether Harrow 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 Harrow today records is this same combined reading — tree, grass, weed and mold in one index.
The Harrow allergy count today is 32 (Low) — the same Total Pollen Index as the pollen count above, in one combined reading.
Pollen count today Harrow: the 5-day forecast
| Day | Total Pollen Index | Band |
|---|---|---|
| Saturday, November 7 | 32 | Low |
| Sunday, November 8 | 31 | Low |
| Monday, November 9 | 34 | Moderate |
| Tuesday, November 10 | 24 | Low |
| Wednesday, November 11 | 14 | Low |
Pollen Atlas forecasts Harrow’s pollen count to peak on Monday at 34 (Moderate) over the next 5 days.
Pollen by type in Harrow
What is driving Harrow’s pollen today
The shape of today’s 32 (Low) is set by weed pollen at 37 (Low on its own scale) — about 52% of the four category readings added together, 3 points clear of the next category, tree pollen at 34. 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 United Kingdom 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 Harrow, so the drivers have to be read from the category split above — it shows how much of today’s total each category is actually carrying, and plant detail returns here automatically on any day the feed includes it.
Across the five-day window the Total Pollen Index runs from 14 to 34, changing band 2 times. Today’s 32 sits 5 points above the window’s average of 27 — a moving window, worth reading day by day rather than from the average.
Plants affecting Harrow now
Detailed plant-by-plant readings for Harrow 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 34 (Low).
Grass pollen is one of the categories with a non-zero reading today, at 0.6 (Low).
Weed pollen is one of the categories with a non-zero reading today, at 37 (Low).
In the Atlantic West pattern, the plants that typically shape this city’s year are early hazel and alder, a spring birch and oak wave, late-spring and summer grasses, and a modest late-summer weed finish — 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.
Harrow pollen through the year
Three chapters make the United Kingdom pollen year, and Harrow follows them in the Atlantic West order. The tree chapter: hazel and alder can open as early as February in mild winters, and the main tree wave — birch, then oak — builds through spring to a May peak. The grass chapter: grasses hold from late May into July, peaking in late spring and early summer. The weed chapter: weeds are the minor closing act — mugwort through late summer, with ragweed localised and generally light this far west. Mold tracks the region’s Atlantic humidity rather than a flowering calendar, and it fills the gaps between chapters.
No United Kingdom allergy season guide is published yet, so this page does not single out signature pollens for Harrow — the calendar above is the Atlantic West regional pattern, and the plant detail on this page names what today’s feed actually records.
November falls between the main chapters of the United Kingdom 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 9 months of the United Kingdom year, February to October — leaving a quiet gap of roughly 3 months in the depth of the off-season. No United Kingdom allergy season guide is published yet — this calendar follows the Atlantic West regional pattern. See Harrow pollen count rankings and Harrow on the pollen heatmap.
How to read this index
Pollen Atlas reports the Harrow 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 Harrow, United Kingdom 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.
Harrow in today’s national picture
At 32 (Low), Harrow ranks joint 10912th of the 90896 cities Pollen Atlas tracks today — in the middle of the national table. The highest reading in the country today is Beja, Portugal at 52, and the lowest is Los Ángeles de San Rafael, Spain at 5. The whole table spans 47 points today — a wide-open day, when the top and bottom of the table are effectively in different seasons.
Around Harrow: Greenhill, United Kingdom (1 km away) reads 32 (Low); Headstone, United Kingdom (2 km away) reads 32 (Low); Harrow Weald, United Kingdom (4 km away) reads 32 (Low). Harrow reads exactly level with its nearest tracked neighbour today. Across United Kingdom’s 3713 tracked cities, today runs from 9 in Lisburn to 44 in Baschurch.
Pollen totals are population numbers; symptoms are personal. The same reading can leave one Harrow resident untouched and floor another, depending on which pollens they are sensitised to. If this pattern finds you every season, allergists in Harrow, United Kingdom 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.
Harrow in its local area
Harrow sits 0.7 km southeast of Greenhill, United Kingdom — the anchor of the forecast-point group this reading belongs to. Within the group of 2, Harrow ranks joint 1st; across United Kingdom’s 3713 tracked cities, it ranks joint 551st today.
Like every Pollen Atlas city page, the Harrow, United Kingdom pollen count is refreshed each morning.
Nearby cities
- Greenhill pollen count (1 km away)
- Headstone pollen count (2 km away)
- Harrow Weald pollen count (4 km away)
- Wembley pollen count (4 km away)
- Pinner pollen count (4 km away)
- Northolt pollen count (4 km away)
From Pollen Atlas News
See how Harrow ranks in today's pollen count rankings — the worst cities for allergies today
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).