UTMB Weather Guide
Weather conditions at the Ultra-Trail du Mont-Blanc in the Alps.
UTMB circles Mont-Blanc through France, Italy, and Switzerland—mountain weather at its most variable.
UTMB Weather Overview
Setting: Alpine mountains, 31,000+ feet of elevation gain.
When: Late August.
What's possible: Everything from heat to snow.
The UTMB Weather Reputation
Famous for variability:
- Sunshine and beautiful
- Rain and mud
- Snow at high passes
- All in the same race
Weather Through the Course
Valleys: Can be warm.
High passes: Cold, exposed, potentially severe.
Night sections: Cold regardless of day weather.
Mandatory Gear Explained
UTMB requires:
- Waterproof jacket
- Warm layers
- Hat and gloves
- Survival blanket
Because: Mountain weather can turn deadly.
Historical Weather
Recent years: Everything from perfect to brutal.
Race sometimes modified: For dangerous conditions.
UTMB weather demands respect. Alpine conditions can change rapidly—carry all mandatory gear.
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