North Cascades National Park weather in August
August in North Cascades National Park: cool, dry, with clean air — one of the best months to visit.
#1 of 12 months in North Cascades National Park · #16 of 604 destinations to visit in August · comfort 94/100 (tier S)
Updated June 2026 · climate normals from ERA5 reanalysis
North Cascades National Park climate normals — August
| Daytime high | 16°C / 61°F | 🙂 cool |
|---|---|---|
| Nighttime low | 4°C / 39°F | |
| Feels like (high) | 14°C / 57°F | |
| Rainfall | 27 mm / 1.1 in | ☀️ dry |
| Rainy days | 7 days | |
| Humidity | 64% | 💧 humid |
| Dew point | 3°C / 38°F | |
| Sunshine | 11.3 h/day | |
| Daylight | 14.3 h | |
| Wind | 9 km/h / 5 mph | |
| Air quality (US AQI) | 44 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Where is North Cascades National Park?
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North Cascades National Park in August — FAQ
- Is August a good time to visit North Cascades National Park?
- August in North Cascades National Park: cool, dry, with clean air — one of the best months to visit. It ranks #1 of 12 months for North Cascades National Park on SeasonMap's comfort score (94/100).
- What is the weather like in North Cascades National Park in August?
- In August, North Cascades National Park averages a daily high of 16.2°C and a low of 4.1°C, with about 27.1 mm of rain over roughly 7.4 rainy days.
- What is the air quality in North Cascades National Park in August?
- North Cascades National Park has a mean US Air Quality Index of about 44 in August.