Best Time to See Monarch Butterflies in New Hampshire
August, September and July is the best time to see monarch butterflies in New Hampshire. Based on 3,794 verified iNaturalist observations, here is exactly when monarch butterflies are most active across the year in New Hampshire.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated June 28, 2026.
Monarch · Michael Nerrie CC BY
Migratory Monarch · Steven Lamonde CC BY
Monarch · Michael Nerrie CC BY
3,794 verified observations of monarch butterflies in New Hampshire, recorded across 7 months of the year on iNaturalist.
When monarch butterflies are recorded in New Hampshire
Peak month
August
1,383 records (36.5% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 0 | 0% |
| February | 0 | 0% |
| March | 0 | 0% |
| April | 0 | 0% |
| May | 15 | 0.4% |
| June | 110 | 2.9% |
| Julypeak | 981 | 25.9% |
| Augustpeak | 1,383 | 36.5% |
| Septemberpeak | 1,094 | 28.8% |
| October | 197 | 5.2% |
| November | 14 | 0.4% |
| December | 0 | 0% |
Monarch Butterflies you are most likely to see
| Species | Verified observations |
|---|---|
| Monarch | 3,794 |
Weather to expect, source Open-Meteo
Typical weather in New Hampshire
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 72 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 24°F | 8°F | 4.1" |
| Feb | 25°F | 8°F | 3.6" |
| Mar | 34°F | 18°F | 3.3" |
| Apr | 45°F | 29°F | 5.2" |
| May | 58°F | 40°F | 4.1" |
| Jun | 67°F | 50°F | 4.8" |
| Julbest time | 72°F | 57°F | 7.1" |
| Augbest time | 70°F | 56°F | 4.5" |
| Sepbest time | 63°F | 48°F | 4.5" |
| Oct | 53°F | 39°F | 5.6" |
| Nov | 38°F | 24°F | 4.2" |
| Dec | 30°F | 17°F | 6" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for New Hampshire. Weather varies year to year, so treat these as a guide.
More on monarch butterflies in New Hampshire:
Sightings of monarch butterflies in New Hampshire peak in August, when 1,383 of the year's 3,794 verified observations are logged — about 36.5% of the annual total. Activity stays high through August, September 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 New Hampshire 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 New Hampshire
- Appalachian National Scenic Trail — National Scenic Trail
- Saint-Gaudens National Historical Park — National Historical Park
Frequently asked questions
What is the best month to see monarch butterflies in New Hampshire?+
August is the single best month, and the broader peak window runs through August, September and July, based on 3,794 verified iNaturalist observations.
When are monarch butterflies hardest to see in New Hampshire?+
January is the quietest month for monarch butterflies in New Hampshire, with no verified records on iNaturalist.
Are monarch butterflies active year-round in New Hampshire?+
Monarch butterflies are recorded in 7 of 12 months in New Hampshire, concentrated around August and September.
More places to see monarch butterflies
More wildlife in New Hampshire