The weather on Snowdon can vary considerably, and your clothing choices should prepare you for the worst while you hope for the best.
Essential items of clothing you should always have when climbing Snowdon in the summer are:
Fleece jacket or top
Base layer top or T-shirt
Walking trousers (not jeans)
Does Snowdon (Yr Wyddfa) get really hot in the summer?
Generally, because of lapse rate, Snowdon is 10°C colder at the summit than it's base. Factor in the wind chill, and it'll feel like the temperature is much cooler.
In spite of the cooling effect of the lapse rate, it can get hot on the summit, with temperatures occasionally topping 30°C. This is definitely the exception and not the rule.
It is good practice to check the weather forecast for the car park and summit and pack accordingly. It is also good to remember that the weather forecast is frequently wrong, so you should be prepared for this.
What are the dangers of hot weather when mountain walking?
Every summer, there are numerous mountain rescue callouts on Snowdon for people suffering from heat exhaustion and, worse, heat stroke. Make sure you know how to prevent them, their signs and what to do if someone develops symptoms.
Sunburn and dehydration are probably the most common dangers, which can be easily avoided with sun cream, a sun hat, and plenty of water.
It might be sensible to do an easier route on a hot day, we recommend the Llanberis Path or Snowdon Ranger Path.
Thunder and lightning are more likely in the summer and pose a very real danger. Last year two people were struck by lightning on the summit.
Take a look at our article for more information about the Dangers of Climbing Snowdon.
What is it like at the top of the mountain in summer?
Snow can persist near the summit well into May and as early as October. The temperature at the summit can vary wildly from a few degrees to over thirty degrees. The average summer temperature is around 15°C.
Visibility is also wildly erratic. One minute you can be in thick fog, barely able to see 10m and the next second the cloud lifts, and you will have amazing views for over 100km.
If it is raining anywhere in Wales, it is likely to be at the top of Snowdon. Appropriate clothing such as a decent waterproof jacket, is essential even if the weather forecast is predicting it to be dry.
Windspeed is faster the higher up you go, with the summit of Snowdon being totally exposed to the prevailing wind. The windspeed can make walking more difficult and arduous, and potentially dangerous at times.
What types of materials to wear for hiking in hot weather?
Good clothing makes a big difference to your comfort and enjoyment on a hot day. A good layering system is key to staying dry and comfortable and the types of clothing you choose should be:
Light in colour
Moisture-wicking fabrics (some include Bamboo)
Synthetic fibres such as polyester
UPF (Ultraviolet Protection Factor)
Waterproof jackets and walking boots aside, you don't need to go out and buy specialist hiking clothing. Select items that you already own that are lightweight and light in colour, as this will make a big difference on a hot day. Modern gym clothing made of synthetic fibres are a fantastic alternative to specialist hiking clothing as a base layer. It does the same job of wicking moisture away from your skin.
What snacks are best to climb Snowdon?
Snacks with a high GI (Glycaemic Index) content are perfect as they deliver a rapid increase in blood glucose, giving you energy quickly.
Foods which are high in sugar have a high GI index. Foods such as jelly babies, energy bars, cereal bars and even fizzy drinks are perfect.
You can sometimes buy snacks from the Snowdon summit café, which uses the Snowdon mountain Railway to transport them up or from the snack bar on the Llanberis Path. These cafes are not always open, especially outside of the summer and in bad weather.
On a hot day, make sure you take plenty of water. Each person will probably need around 3 litres.
If you're a cheese lover, you may want to sneak a few bites into a cool bag or box. Check out our blog all about Snowdonia Cheese which also includes other foods to eat for your climb.
The ultimate Snowdon summer kit list
This is a comprehensive list of everything needed to climb Snowdon in all the conditions you might experience in the summer. Check the weather forecast before you set off and pack accordingly. We recommend you pack:
Fancy walking socks
Base Layer or T shirt
Warm fleece or top
Spare warm layers
Rucksack liner (or plastic bag to keep your kit dry)
Map and compass (and knowledge of how to use maps)
Water (2 litres at least)
First aid kit (Blister plasters and painkillers are recommended)
Head torch & spare batteries (especially in spring and autumn)
Mobile Phone (in waterproof case or bag)
Warm drink in a flask
Toilet paper (& a bag to dispose of it in)
Plastic bag for rubbish
Group shelter and/ or survival bag
When the forecast is for hot weather or high UV, you should take extra water and items to protect you from the sun. This would include:
For normal or if the forecast is for wet, windy, cold or overcast weather, it might be best to take:
Additional warm layers
Warm drink in a flask
Group shelter and/ or survival bag
As a mountain professional, I almost always take sun cream, gloves, and layers in spite of the forecast.
Should you wear layers when hiking in the summer?
A good layering system is key to maintaining a comfortable temperature. Adding and removing thin layers will help regulate temperature, reduce sweating, and keep you comfortable.
The best layering system for mountaineering in summer is a base layer, mid layer and waterproof outer shell...
This should keep you cool and dry by wicking moisture away from your skin. Your base layer should consist of...
Base layer top
This is the layer which provides most of the warmth by reducing heat loss. Several thin layers work better than one thicker layer. The colder and wetter the forecast the more spare layers you should take:
Fleece and spare fleece or jacket
Gloves and spare gloves
Waterproof shell/ Outer shell/ Hard shell
This keeps you dry when it is raining and also acts as a windproof barrier, significantly reducing wind-chill.
Book your summer guided tour with Walk Snowdonia now
Book one of our guided walks and we will give you advice and a detailed kit list based on the time of year, weather forecast and route. In addition, we will be able to offer advice and answer all of your clothing and equipment questions as part of our professional, friendly, and helpful service. Contact us today!
How do I stay cool whilst protecting myself from sunburn?
Government advice in hot weather is to 'avoid heavy activity' and 'walk in the shade'. Both of these are pretty much impossible when you climb Snowdon, but there are some really good hacks to keep cool even when it is hot:
avoid hiking in the hottest part of the day (Sunrise or sunset hikes are cooler)
wear a hat & light clothing
take plenty of water (at least 3 litres on a hot day)
put water in the fridge the night before
put ice cubes in the water bottle
submerge your hat in cold stream then put it on your head
dip your feet or go for a swim in the plunge pools on the Watkin Path
buy a cold drink from the café on the Llanberis Path (if it's open)
choose a route on the windward side of the mountain
Is it better to wear shorts or trousers in the summer when climbing Snowdon?
As a general rule, trousers are better than shorts. Trousers are warmer, and importantly they protect your skin from wind chill or sunburn.
In addition, a hidden danger in the mountains is Lyme Disease, which is carried by infected Ticks. Trousers reduce the chance of being bitten by Ticks.
Is it better to wear hiking boots or walking shoes when climbing Snowdon?
Walking boots are better as they have ankle support, good grip, foot protection, and are waterproof. The good grip and ankle support will significantly reduce your chances of injury and slipping on wet rock or loose scree, such as on the Watkin Path or Llanberis Path.
Walking shoes have good grip and are often waterproof but don't have ankle support. Twisted and broken ankles are the cause of around 20% of Mountain Rescue call outs, and most of these could be prevented by wearing a walking boot with ankle support.
Summer is the most reliable time of the year for good weather and good views on Snowdon. Check the weather forecast before you set off, pack accordingly and always pack the essentials.
A good layering system is the best way to regulate body temperature when hiking. Numerous thin layers work best.
Other useful resources you might be interested in include...