Weather, conditions, and the discipline of turning around

City forecasts do not describe trailheads

Elevation, aspect, and distance from the coast can produce completely different conditions within an hour's drive. A sunny city genuinely tells you nothing about a mountain pass, a canyon, or an exposed ridge.

Look for a forecast for the elevation you will actually be at, and check the snow level separately in any season where it might matter. Where a land manager publishes current conditions, that source beats any forecast.

Set the turnaround rule before you leave

A turnaround decision made in advance is a rule. Made on the day, on a ridge, having driven two hours, it is a negotiation you will usually lose against your own investment.

Pick a time, a weather condition, or a landmark, and agree it out loud with the group. It costs nothing when conditions are fine and it is the entire safety margin when they are not.

The specific risks worth understanding

Three conditions cause trouble far out of proportion to how often they are discussed, and all three are counterintuitive.

• Flash flooding in canyons and slots, which is caused by rain miles upstream and can happen under a clear sky overhead
• Lingering snow on high traverses months after the valley is clear, which turns a walk into a route needing traction
• Heat on an exposed climb out, which is dangerous rather than uncomfortable and is worst on the return leg when water is low

Verify anything with consequences

Permits, water crossings, road access, and seasonal closures all change, sometimes at short notice. For any of these, check the official source rather than a description written at an unknown point in the past.

This applies to this site as much as any other. Every listing here shows when it was last updated and what level of verification it has had — treat both as part of the information, not as fine print.