Weather
Read cloud formations to forecast weather
Clouds give 6–24 hours of advance warning about incoming weather when you know what to look for.
Topic summary
Clouds give 6–24 hours of advance warning about incoming weather when you know what to look for.
Intended uses
Weather skill (all levels, ~10 min practice)
Step-by-step
High wispy cirrus 'mare's tails' invading a clear sky mean a warm front is 12–24 hours out — expect rain within a day.
Cirrus thickening to a smooth cirrostratus veil (halo around sun or moon) confirms front is closer — often within 12 hours.
Middle-level altostratus turning to low nimbostratus with a lowering, darkening ceiling means active precipitation is beginning.
Tall cumulus towering into anvil-topped cumulonimbus in warm afternoons means thunderstorms — get off ridges and out of exposed water within an hour.
Clearing to fair-weather cumulus with flat bases and blue sky between means the system has passed.
Tip: Watch cloud motion, not just shape. Fast-moving clouds mean strong upper winds and rapidly changing weather.
Related outdoor skills
Educational reference only. Wilderness conditions change fast — practice in low-stakes settings, take a certified wilderness first-aid course, and confirm regional regulations before you rely on any of these skills in the field.