Grass pollen in Seattle usually starts winding down in July and is mostly over by early to mid-July , though some years it can linger a bit longer into late July or even September at lower levels. Seattle sources describe grass season as running from mid-May through early July , while other local guides note that it can extend through September in some years, so the exact end depends on weather and the year.

What that means in practice

  • Peak season: May and June.
  • Typical end: Early to mid-July.
  • Occasional longer tail: Late summer in some years, especially if conditions stay dry and warm.

Quick scoop

For most people in Seattle, the toughest grass pollen stretch is late spring into early summer , and by now in early July the season is often tapering off. Rain and cooler weather usually help bring counts down.

Today’s takeaway

If you’re tracking symptoms, the best rule of thumb is: grass pollen is usually fading by July in Seattle, but it can still show up later depending on the season.