I always depend heavily on the seasons for mountaineering when deciding which mountain to climb and when. Knowing when to go into the mountains could be the difference between having an awesome trek and getting stuck in the worst conditions you can imagine.

A general rule of thumb is that spring, early autumn and summer are best for mountaineering. Here, the weather is generally fair and you won’t encounter much snow or extreme winds. This isn’t always valid, though, since some areas are in summer rainfall regions, which will complicate your choice a bit.

In this article, I’ll take a look at the best season for mountaineering and how to understand mountain weather.

Make sure to Avoid these Seasons when Mountaineering

On a mountaineering trip, you want to avoid extreme cold, heavy snowfalls, strong winds and any form of rain. If you’re heading into the mountains at extremely high altitudes, it will probably be quite hard to avoid these, since most places at extreme altitudes are permanently cold and snow-clad.

The best season for mountaineering really depends on the climbing location, however the months during winter and early spring are often subject to rougher weather and more snow.

The key is to understand the weather in the area you’re planning to trek in and take proper precautions.

Regardless of the area, it’s usually a good idea to avoid winter, even in areas that aren’t generally snow-clad. In most areas, winter weather is worse than in the other seasons and also harder to predict.

Not long ago I wrote an article about the dos and don’ts of mountaineering. If you are just starting out and are unsure about where to begin, I’d recommend reading that article. You can find my article here.

Understanding Mountain Weather and Seasons

Mountain weather is notoriously unpredictable. Even the best weather forecast is sometimes inaccurate.

This means you could head out on a sunny morning thinking that you have an entire balmy day’s hike ahead of you, only to see some clouds building up around mid-morning and getting stuck in a thunderstorm around lunch. That would suck and could have serious implications for your safety.

Understanding mountain climates will give you a bit of an edge when it comes to planning your trip and reading the weather while you’re trekking.

In general, increased altitude increases wind and precipitation (either rain or snow).

Along with this, temperature decreases by roughly 6°C for every 1000m ascended.

This means that mountain weather is generally colder, wetter and windier than the low-lying areas surrounding the mountain.

Here are some basics to use when you’re figuring out the weather for your trip:

Weather Forecasts and What’s Different in Winter

Check the weather online for the actual location of your climb, not the nearest town. The nearest town could well be a kilometer lower than your planned route, having a significant impact on what you’re likely to encounter. Don’t just check the temperature – take note of the wind speed and forecast precipitation.

Most weather sites have an hourly forecast. This will indicate lots of extras, like freezing altitude and lots of other goodies that will help you plan ahead and potentially postpone your trip by a day or two.

Locals

The locals know their area and the weather that goes with it. They’ll be able to tell you if it’s a good idea to head out when you’re planning to go, things that generally go wrong and some stuff to look out for when you’re in the mountains.

They’ll be able to tell you how the weather usually turns, which direction the rain comes from and how cold the nights actually get.

Eyes to the Sky

This is your most important tool while out trekking. If you see the weather changing faster than expected, adjust your plans accordingly. It’s never a good idea to get stuck outside in bad weather.

As you build up experience, you’ll get better at reading mountain weather. It helps taking someone with you that has more experience and can teach you to read the weather properly.

Understand the Clouds

Different types of clouds indicate different types of weather. If you understand what different types of clouds look like and what they mean, you would be able to predict weather a storm is heading your way and how severe it’s likely to be. Here are some types of clouds to look out for:

• Lenticular clouds: aka Hogs-back clouds. These are known for their distinct shape. When you see these accompanied by strengthening winds, you can bet your bottom dollar that a storm will hit in the next 6-24 hours.
• Cirrus clouds: these occur at high altitude and are wispy. If you see these alone, everything’s fine. If you see them combined with low stratus clouds, you can probably expect some rain.
• Cumulus clouds. These are large and puffy and usually indicate fair weather. If they grow bigger, however, building up many heads or bumps, they bring bad weather: they turn into cumulonimbus clouds, bringing hail, strong wind, thunder and lightning.

Other Storm Indicators

There are other indicators to watch out for when it comes to the weather. Here are some of them:

• Drop in air pressure indicates a storm is approaching. This you’ll see if you’re carrying a pocket barometer. Note that an increase in altitude would also cause a drop in air pressure, so take that into account before freaking out.
• Conditions higher up are always worse. If the weather at lower altitudes is moderately bad, you’re likely to hit some foul weather higher up. There are exceptions to this rule, however, since sometimes a low cloud system only affects the lower regions. Once you get through the clouds, you can encounter gorgeous weather ideal for hiking.

Conclusion

Mountaineering, as with most outdoor sports, is best done in good weather. Pick your season based on local conditions and always take the current weather into account.

For beginners, I’d recommend to get most climbs done during late spring, summer or in some cases autumn. Avoid the winter months since you can get stuck in snowy conditions and more technical/icy climbs.

It’s a good idea to learn to read mountain weather accurately in order to keep yourself and your team safe. Happy adventures!