← Ontario Night Sky · All sites tonight
Poor (Medium confidence)
No sustained clear window; brief gaps possible (min cloud 19%).
Fri 6:00 p.m. – Fri 6:00 p.m. (1h, 19% mean cloud)
Parts of Yellowstone's Lamar Valley sit in Bortle Class 1 — as dark as skies get in the Lower 48 — and on a clear moonless July night visitors regularly gather at pullouts between Mammoth Hot Springs and Tower Junction just to look up. It's one of the largest expanses of genuinely dark sky left in the continental United States.
Drive from Toronto: Multiple entrances in Wyoming and Montana; West Yellowstone, Montana is the most common gateway, about 5–6 hours from Salt Lake City.
Best time of year: Late summer through fall for clear, dry nights; Lamar Valley in the park's northeast is the most reliably dark section.
https://koohxdehsweadgdegrly.supabase.co/functions/v1/mcpThis is a build-time snapshot — the live forecast at https://ontarionightsky.com/?site=yellowstone-np updates continuously.