Historical Race Day Weather for the Boulderthon - Boulder Marathon

September 27, 2026

Race day snapshot

Partially cloudy

Start Line Conditions

Start Temp 60°F 16°C

Start Humidity 49% Humidity

Wind WSW 4 mph Wind

Race day high 70°F 21°C

Race day low 49°F 9°C

PR Score 92.43 Normal score 92.68

Course Score 92.68 Course-only Score

Course-adjusted pacing

Want to run your best Boulderthon - Boulder Marathon?

Boulderthon - Boulder Marathon Pace Bands are adjusted for the specific terrain of the course, your goal time, and pacing strategy.

Build your Boulderthon - Boulder Marathon pace band

Easy to useCourse-aware pacing, goal-time based splits, and a cleaner race day plan.See all pace bands

September 28, 2025

Race day snapshot

Clear

Start Line Conditions

Start Temp 59°F 15°C

Start Humidity 59% Humidity

Wind No Wind Wind

Race day high 77°F 25°C

Race day low 51°F 11°C

PR Score 91.83 Normal score 92.68

Course Score 92.57 Course-only Score

September 29, 2024

Race day snapshot

Clear

Start Line Conditions

Start Temp 64°F 18°C

Start Humidity 34% Humidity

Wind SSE 0 mph Wind

Race day high 85°F 29°C

Race day low 55°F 13°C

PR Score 91.00 Normal score 92.68

Course Score 91.81 Course-only Score

October 8, 2023

Race day snapshot

Clear

Start Line Conditions

Start Temp 56°F 13°C

Start Humidity 32% Humidity

Wind W 3 mph Wind

Race day high 72°F 22°C

Race day low 45°F 7°C

PR Score 91.81 Normal score 92.68

Course Score 91.81 Course-only Score