Can I climb todayToday: Yes. Dry for the rest of the day.
How to read the dial
- Dry
- Fast‑drying sectors only
- Wet
- Now
- When it dries
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The best-known areas today
Climb indoors instead
Bouldering gyms near the forest, for a wet day.
Before you go
Flagstaff Mountain (Boulder) after rain
Flagstaff Mountain: sandstone boulders in open country, in Colorado, United States. The nearest other areas here are Boulder Canyon (9 km), Clear Creek Canyon (30 km) and Three Sisters Park (42 km).
Is Flagstaff Mountain dry today?
The answer at the top of this page comes from NOAA's forecast and how fast sandstone dries, and it's updated through the day. Nobody checks the rock in person, so touch the holds before you climb.
How long does Flagstaff Mountain take to dry after rain?
Flagstaff Mountain is sandstone, which soaks up rain and stays weak inside for a while after the surface looks dry. These times are the model's estimates, tuned on Fontainebleau sandstone and not checked here. After a proper soaking (2 mm of rain or more), sunny, windy boulders need about 18 hours of dry weather, most of the boulders about 30 hours, and shaded ones about 42 hours. A light shower needs less. Wind, sun and dry air shorten the wait, and above about 92% humidity the model won't call the rock dry.
Can you climb at Flagstaff Mountain when the rock is wet?
Wet sandstone breaks. If a hold feels cool or damp, leave it for another day.