Signs of changing weather

Mountaineering, like any other activity in the mountains, depends on the weather. Often the weather forecast is a determining factor when deciding on a route and directly affects the safety of travel in the mountains.

Official weather forecasts very often give information that differs from what is actually happening on the mountain or in your chosen area.Therefore, a climber needs to know and be able to correctly interpret signs of weather changes.

We have collected basic weather signs for you that you can use in addition to the forecast or in case there is no forecast.

Signs of worsening weather:

1. Atmospheric pressure drops;
2. Morning dew does not dry for a long time;
3. The appearance of clouds from early morning;
4. Cirrus clouds appear;
5. Clouds appear in the form of lenses;
6. Clouds at different levels move in different directions;
7. Circles (halos) appear around the Sun or Moon;
8. In summer, the clouds darken at midday;
9. At night the temperature is higher than usual;
10. At midday, cumulus clouds form quickly;
11. The mountain-valley cycle is disrupted;
12. Contrails from aircraft do not dissipate immediately, but are visible in the sky for a long time;
13. Cirrus clouds that thicken and gradually begin to cover the entire sky;

Signs of improving weather (clear weather without precipitation expected):

1. Atmospheric pressure is stable or rising;
2. It’s cold at night;
3. The morning fog clears within two hours after dawn;
4. There are fewer clouds after 4 pm;
5. The sun at sunset looks like a ball of fire;
6. Steady cycle of mountain-valley winds;

You can read about what resources to use to forecast weather in the mountains in our article.