How the heatmap works
Color = how good that factor is. Blue = best, red = bad. Colorblind-friendly palette (no red-green). The number in each cell is the raw value.
- score
- The overall call, and the order of each heatmap: the average of the four factors below, pulled halfway to the worst one — so one bad factor (wet rock, 85°F, a 90% rain chance) sinks the day. GO ≥ 70 · MAYBE ≥ 45 · else NO. Periods are 8am–8pm; Today is what's left of today's daylight and drops off in the evening.
- temp
- Number = forecast air temp (the period's high), matching the chart. Color scores the sun-warmed rock temp for the crag's aspect, shown as ☀78° when the sun warms it. Sport crags ideal 50–70°F, boulder crags 45–55°F. Bad below 35°F or above 80°F.
- dew
- Worse of two: high humidity (dewpoint 60°F+ = greasy holds) or low temp-to-dew spread (<5°F means rock will condensate, slicking up).
- rock
- Is the rock dry? Counts all rain — overnight too — against each crag's drying time (heavy rain can take 1–2 days). dry · dry 11a (dry from ~11am) · wet 2p (wet from ~2pm) · wet. The small number is the rain during the period plus the 12h before. Overhung crags score wet rock at half, not zero: the steep stuff stays climbable.
- precip
- Max chance of rain during that period. 0% = best, 100% = bad.
- ⛈ storms
- A ⛈ and red ring flag thunderstorms in that period's forecast, with thunder's own chance (⛈ 17%) — a hard no-go on exposed cliffs and approaches. Best windows skip storm hours; the chart marks them; per-crag pages show a banner.