When should you visit? The numbers know.
VisitWhen ranks every month for all 63 US national parks from three official datasets: monthly crowd statistics (NPS, 2021–2025 average), weather normals (NOAA 1991–2020) and computed daylight — an honest, formula-based verdict for every park, every month. See exactly how it's computed →
Where to go in October — top computed picks
Lassen Volcanic National Park
Best month of the year · 78/10035% of peak crowds · highs 59°F · 11.2h daylight
Theodore Roosevelt National Park
Best window · 78/10034% of peak crowds · highs 58°F · 11h daylight
Glacier National Park
Best month of the year · 76/10018% of peak crowds · highs 49°F · 10.9h daylight
Full October ranking — all 63 parks →
Planning ahead: November
Top computed picks if you're booking next month: Gateway Arch · Great Basin · Badlands · Wind Cave · Canyonlands · Mammoth Cave · Mesa Verde · New River Gorge — full November ranking →
Planning ahead: December
Top computed picks if you're booking for December: Shenandoah · Channel Islands · Zion · Gateway Arch · Saguaro · Big Bend · American Samoa · Great Basin — full December ranking →
Every park, month by month
Each park page shows the full 12-month table — crowds as a percentage of the park's peak, temperature and precipitation normals, daylight, seasonal road status — and a computed verdict for each month.
Browse all 63 national parks A–Z →
How the verdict works
Every month gets a 0–100 score: 45% comfort (NOAA temperature and precipitation normals), 35% quietness (official NPS monthly visitation, inverted), 20% daylight (computed from the park's coordinates). Months where a park's headline access is typically closed are penalized and can't be labeled "Best window." No opinions, no sponsored rankings — the formula is public and identical for every park. Full methodology →
Park photos: Badlands — NPS Photo · Isle Royale — NPS Photo / Paul Brown · Wind Cave — NPS Photo · Gateway Arch — NPS Photo/Sue Ford · Lassen Volcanic — NPS Photo / Scott Arnaz · North Cascades — NPS Photo/D.Dixon · Theodore Roosevelt — NPS Photo / Mark Meyers · Glacier — NPS Photo. National Park Service photos are U.S. federal government works in the public domain.
Plan your gear after choosing a park
Check the park's weather and trail conditions before choosing sizes or equipment. These options are starting points for comparison; none is required for every visit.
As an Amazon Associate, VisitWhen earns from qualifying purchases, at no extra cost to you.
- Black Diamond Storm 550 headlampSee price on AmazonView on Amazon
A rechargeable light to consider if your plans include walking after dark. Check battery runtime and carry an appropriate backup.
- Compare hiking footwear on Amazon
Choose for your terrain, fit and intended distance; check sizes and return terms.
- Compare packable rain jackets on Amazon
Compare fit, weather protection and packed size with the conditions on your park page.