Chamonix in August

August weather, activities, events & insider tips

August Weather in Chamonix

24°C (75°F) High Temp

13°C (55°F) Low Temp

95mm (3.7 inches) Rainfall

70% Humidity

Is August Right for You?

Advantages

Perfect hiking weather with 11+ hours of daylight and warm temperatures ideal for high-altitude trails above 2,000m (6,562 ft)
Peak wildflower season in alpine meadows - rhododendrons, gentians, and edelweiss in full bloom from 1,500-2,500m (4,921-8,202 ft)
All cable cars and mountain huts operating at full capacity with extended summer hours (typically 8am-5pm)
Warmest lake temperatures of the year at Lac Blanc 16°C (61°F) and Lac des Gaillands 20°C (68°F) for alpine swimming

Considerations

Peak tourist season means 3x higher accommodation prices and crowds of 15,000+ daily visitors at Aiguille du Midi
Afternoon thunderstorms 60% of days between 2-5pm force early starts for high-altitude activities
Trail erosion and overcrowding on popular routes like Lac Blanc require 6am starts to avoid bottlenecks

Best Activities in August

Mont Blanc Massif High-Altitude Hiking

August offers the most reliable weather window for accessing high-altitude trails above 2,500m (8,202 ft). The Vallée Blanche glacier access and Tour du Mont Blanc sections are at their most stable. Perfect 13°C-24°C (55°F-75°F) temperature range means comfortable hiking in base layers with warm conditions even at altitude. Snow has cleared from most passes, making technical routes like the Grand Balcon Nord accessible to intermediate hikers.

Booking Tip: Book guided glacier walks 3-4 weeks ahead through certified IFMGA mountain guides. Day hikes cost €45-85 per person for cable car access. Multi-day hut-to-hut treks typically €380-550 including accommodation. Start early (6-7am) to avoid afternoon storms and crowds.

Aiguilles Rouges Nature Reserve Wildflower Photography

August is peak wildflower season with over 600 alpine species in bloom across the Aiguilles Rouges massif. The Flégère-Brévent area offers perfect morning light (golden hour 6:30-8am) for photography with Mont Blanc backdrop. Lower humidity in early morning creates crystal-clear visibility extending 50km+ (31+ miles). Afternoon thunderstorms create dramatic cloud formations perfect for moody landscape shots.

Booking Tip: Photography workshops cost €120-180 for full-day sessions with local experts. Access via Flegere cable car €32 return. Book botanical guided walks 10-14 days ahead. Best shooting locations require 2-4 hour moderate hikes at 1,800-2,300m (5,906-7,546 ft) elevation.

Mer de Glace Glacier Experience

August provides optimal conditions for glacier exploration with stable ice conditions and the warmest temperatures for underground ice cave visits. The historic railway operates extended hours and the glacier is most accessible. Ice caves maintain -2°C (28°F) year-round, creating a refreshing 26°C (47°F) temperature contrast from valley heat. Clearest glacier views and safest crevasse conditions for guided glacier walking.

Booking Tip: Montenvers train tickets €37 return, runs every 20 minutes 8am-6pm. Ice cave entry additional €8. Glacier walking courses €95-140 with certified guides, book 2-3 weeks ahead. Crampons and equipment provided. Allow 4-5 hours total including train journey and glacier time.

Via Ferrata and Rock Climbing

August offers ideal rock conditions with dry granite and extended daylight until 9pm for evening climbs. Rock temperatures warm enough for comfortable belaying but not scorching hot like July. The famous granite spires have minimal morning condensation and afternoon storms clear quickly. Perfect conditions for multi-pitch routes on Aiguilles with stable weather windows of 4-6 hours before afternoon thunderstorms.

Booking Tip: Via ferrata courses €85-120 for half-day with guide and equipment. Rock climbing instruction €140-200 full day. Book through certified mountain guide services 2-3 weeks ahead. Via ferrata routes like Curalla operate independently, equipment rental €25-35/day. Start climbs by 7am to avoid afternoon weather.

Alpine Lake Swimming and Picnicking

August delivers the warmest alpine lake temperatures with Lac des Gaillands reaching swimmable 20°C (68°F) and higher altitude lakes like Lac Blanc at refreshing 16°C (61°F). Perfect for post-hike recovery with impressive mountain reflections in calm morning conditions. Long daylight hours allow for extended lakeside picnics until 8:30pm sunset. Minimal crowds at higher lakes accessed by hiking.

Booking Tip: Lake access is free but parking at popular spots like Lac des Gaillands fills by 10am (€2/hour). Higher lakes require 1-3 hour hikes with elevation gains of 300-600m (984-1,968 ft). Pack picnic supplies from Chamonix markets - local cheese and bread costs €8-15 for two people. No facilities at alpine lakes.

Paragliding and Scenic Cable Car Tours

August provides the most reliable thermals for paragliding with consistent afternoon lift between 12-4pm before thunderstorms. Crystal clear visibility extends across the entire Mont Blanc massif and into Switzerland and Italy. Cable cars operate at full capacity with extended hours, offering access to 3,842m (12,605 ft) Aiguille du Midi for glacier panoramas. Minimal wind interference and stable atmospheric conditions.

Booking Tip: Tandem paragliding flights €95-140 depending on flight duration and launch point. Book 5-7 days ahead as weather dependency creates cancellations. Cable car day passes €67-89 for multiple lifts. Aiguille du Midi can have 45+ minute queues, purchase priority tickets online. Morning flights offer calmest conditions, afternoon flights the strongest thermals.

August Events & Festivals

Mid August

Fête des Guides (Guides Festival)

Annual celebration honoring Chamonix's mountain guides with traditional ceremonies, climbing demonstrations, and local food stalls. Features authentic Savoyard music, folklore performances, and guided historical walks through old Chamonix. Local restaurants offer special menus featuring traditional dishes like tartiflette and diots.

Late August

Ultra-Trail du Mont-Blanc (UTMB)

World's most prestigious ultra-trail running event with 10,000+ participants racing 171km (106 miles) around Mont Blanc massif. The valley buzzes with international trail running community, gear exhibitions, and outdoor film screenings. Spectacular viewing points along the route offer glimpse of elite mountain athletes.

Essential Tips

What to Pack

Lightweight merino wool base layers - temperature swings from 13°C to 24°C (55°F to 75°F) require adaptable layering system

Waterproof shell jacket with pit zips - afternoon thunderstorms deliver 95mm (3.7 inches) monthly rainfall in sudden downpours

SPF 50+ glacier glasses and zinc sunscreen - UV reflection off snow and ice at altitude intensifies 8-level UV index by 10-15%

Microspikes or lightweight crampons - early morning trails above 2,000m (6,562 ft) may have frost patches until 9am

Quick-dry hiking pants and shorts - 70% humidity makes cotton uncomfortable, synthetic fabrics essential for comfort

Insulated water bottle - mountain hut water costs €3-5 per liter, springs available but require purification above treeline

Power bank 20,000+ mAh capacity - mountain hut electrical outlets limited, GPS navigation drains batteries in cold alpine air

Lightweight down vest - evening temperatures drop rapidly after sunset, essential for cable car rides and high-altitude dining

Gaiters and broken-in hiking boots - trail conditions vary from rocky granite to muddy alpine meadows within single hikes

Emergency bivvy sack - afternoon thunderstorms can trap hikers above treeline, weighs only 85g (3oz) but potentially lifesaving

Insider Knowledge

Book the first Aiguille du Midi cable car (8am) to avoid crowds and catch the famous 'golden light' on Mont Blanc's north face - by 10am you'll wait 45+ minutes

Local farmers' markets on Saturday mornings offer authentic reblochon cheese at €12/kg versus €18/kg in tourist shops, perfect for trail picnics

The Petit Train du Montenvers offers half-price tickets after 3pm when most tour groups have departed - better glacier photography light anyway

Valley restaurants close kitchens 2-7pm but mountain huts serve continuous food service - plan lunch stops at altitude for better value and views

Avoid These Mistakes

Starting popular hikes after 8am - trails like Lac Blanc become bottlenecked with 200+ daily hikers, early start ensures parking and peaceful experience

Booking accommodation less than 6 weeks ahead - August prices triple and availability drops to under 15% by July for quality hotels

Ignoring afternoon thunderstorm forecasts - lightning strikes on exposed ridges kill 2-3 hikers annually in the Alps, always check Météo France morning reports