Zion Traverse

The weather window Thursday through Saturday daytime is genuinely good. Highs of 62-64°F with light winds and mostly sunny skies are ideal running conditions for the Traverse. Overnight lows drop to 31°F Thursday and Saturday night, so if you're camping mid-route, plan accordingly. The real constraint is Saturday night: 72% precipitation probability with thunderstorms likely. If you're doing a multi-day push, structure your itinerary to be off the exposed canyon rims and out of the Narrows by Saturday afternoon — don't count on a comfortable exit Saturday evening.

For a 48-mile Zion Traverse, you've got 13h 27m of daylight each day (sunrise 6:47 AM, sunset 8:14 PM). If you're running it as a single push, a 6:47 AM start gives you the full window, but a sub-13.5-hour pace is tight for most runners on this terrain — have a hard turnaround or bailout plan at Kolob Canyons or Scout Lookout if you're behind schedule going into the afternoon. If you're spreading it over multiple days, Thursday and Friday are your best movement days.

The stream flow data in this briefing — Salinas River, Alameda Creek, Llagas Creek — is entirely from central California and has zero relevance to Zion. Disregard those numbers. What matters here is the Virgin River through the Narrows. Spring snowmelt is real right now; the SNOTEL station at Long Lake shows 97 inches of depth still falling, which means sustained melt runoff is likely ongoing. Scout the Narrows entry at the Temple of Sinai and check the Zion NPS flow gauge (Virgin River at Springdale) before committing. If flows are above roughly 150 cfs, the Narrows becomes a serious hazard. Call the Zion Visitor Center the morning you plan to enter.

Heat and hydration aren't the primary concern at these temps, but the canyon walls can amplify radiant heat on sunny afternoons even when air temps feel moderate. Carry more water than you think you need between sources — several sections of the Traverse have long dry stretches. Start Thursday's leg early to lock in the best conditions before Saturday's storm system arrives.