Best Time to See Monarch Butterflies in Oregon
June, August and July is the best time to see monarch butterflies in Oregon. Based on 577 verified iNaturalist observations, here is exactly when monarch butterflies are most active across the year in Oregon.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated June 28, 2026.
577 verified observations of monarch butterflies in Oregon, recorded across 7 months of the year on iNaturalist.
When monarch butterflies are recorded in Oregon
Peak month
June
164 records (28.4% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 0 | 0% |
| February | 0 | 0% |
| March | 0 | 0% |
| April | 0 | 0% |
| May | 17 | 2.9% |
| Junepeak | 164 | 28.4% |
| Julypeak | 136 | 23.6% |
| Augustpeak | 141 | 24.4% |
| September | 88 | 15.3% |
| October | 28 | 4.9% |
| November | 3 | 0.5% |
| December | 0 | 0% |
Monarch Butterflies you are most likely to see
| Species | Verified observations |
|---|---|
| Monarch | 577 |
Weather to expect, source Open-Meteo
Typical weather in Oregon
Recent typical conditions by month, so you can plan a trip around both when monarch butterflies are active and what the weather is doing. The best months to look for monarch butterflies sit around 48 to 83 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 39°F | 26°F | 2" |
| Feb | 38°F | 22°F | 2.4" |
| Mar | 43°F | 25°F | 1.9" |
| Apr | 52°F | 32°F | 2.2" |
| May | 61°F | 40°F | 2" |
| Junbest time | 71°F | 48°F | 1.1" |
| Julbest time | 83°F | 56°F | 0.1" |
| Augbest time | 81°F | 56°F | 0.4" |
| Sep | 71°F | 47°F | 1.2" |
| Oct | 58°F | 37°F | 1.2" |
| Nov | 45°F | 28°F | 2.3" |
| Dec | 37°F | 25°F | 2.4" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Oregon. Weather varies year to year, so treat these as a guide.
More on monarch butterflies in Oregon:
Sightings of monarch butterflies in Oregon peak in June, when 164 of the year's 577 verified observations are logged — about 28.4% of the annual total. Activity stays high through June, August and July.
The quietest stretch is January, February and March, when monarch butterflies are hardest to find — no verified records exist for January. If a reliable sighting matters, plan around the peak window rather than the off-season.
The monarch butterflies you are most likely to encounter in Oregon are Monarch — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see monarch butterflies in Oregon
- Crater Lake National Park — National Park
- Fort Vancouver National Historic Site — National Historic Site
- Lewis & Clark National Historic Trail — National Historic Trail
- Lewis and Clark National Historical Park — National Historical Park
- Nez Perce National Historical Park — National Historical Park
- Oregon Caves National Monument & Preserve — National Monument & Preserve
Frequently asked questions
What is the best month to see monarch butterflies in Oregon?+
June is the single best month, and the broader peak window runs through June, August and July, based on 577 verified iNaturalist observations.
When are monarch butterflies hardest to see in Oregon?+
January is the quietest month for monarch butterflies in Oregon, with no verified records on iNaturalist.
Are monarch butterflies active year-round in Oregon?+
Monarch butterflies are recorded in 7 of 12 months in Oregon, concentrated around June and August.
More places to see monarch butterflies
More wildlife in Oregon