Grass Pollen
GrassesThe grass family as a whole. Grass pollen is the most common trigger of hay fever worldwide, with peak levels in late spring and summer.
In a typical year, Grass Pollen season runs May to September, peaking around June to July.
Where is Grass Pollen highest today?
Live ranking across the cities we track, from today's forecast. Updated daily.
| Locations | Level | Count |
|---|---|---|
| Sarajevo · Bosnia and Herzegovina | X.HI | 112 grains/m³ |
| Faro · Portugal | V.HI | 60 grains/m³ |
| Lyon · France | HIGH | 49 grains/m³ |
| Montpellier · France | HIGH | 49 grains/m³ |
| Dresden · Germany | HIGH | 47 grains/m³ |
| Aarhus · Denmark | HIGH | 46 grains/m³ |
| Rabat · Morocco | HIGH | 46 grains/m³ |
| Prague · Czech Republic | HIGH | 43 grains/m³ |
| Kinshasa · Democratic Republic of the Congo | HIGH | 42 grains/m³ |
| Chișinău · Moldova | HIGH | 41 grains/m³ |
Grass Pollen season by country
Typical windows from our country pollen calendars; the weather shifts them earlier or later each year.
| Country | Season | Peak |
|---|---|---|
| Australia | Sep–Apr | Oct–Dec |
| Germany | May–Sep | Jun–Jul |
| Japan | Apr–Oct | May–Jul |
| United Kingdom | May–Sep | Jun–Jul |
| United States | Apr–Sep | May–Jul |
About Grass Pollen
Grasses are the single biggest cause of hay fever worldwide. The family includes the meadow, pasture and lawn grasses of every temperate region. Because their pollens share closely related allergens, most people who react to one grass react to many: timothy, cock’s-foot, perennial ryegrass and the meadow grasses all count. Symptoms usually begin when the first grasses flower in late spring and last until the last hay meadows are cut or the summer dries the grass out.
In the temperate northern hemisphere the season runs roughly May to August, peaking in June and July. Around the Mediterranean and in the southern United States it starts and peaks a month or more earlier, and warm-climate grasses there can shed pollen for much of the year. In southern Australia and New Zealand the season runs October to January instead. Counts climb on warm, dry, breezy days and fall in rain. Pollen released in the morning often settles back into city streets in the early evening, which is why symptoms can be worse at both ends of the day.