Western States 100 weather

Race-day forecast

June 26 in past years

At the start, 5 AM to 9 PM local time. “Heat” is the typical slowdown at the same effort, from temperature plus dew point, in the hottest hour. From Open-Meteo’s historical weather (ERA5).

About the course

100.2 miles from Olympic Valley over the Sierra crest and down through the canyons to the track in Auburn, starting at 5 AM. The weather is two races: cold, sometimes snowy high country in the morning, then canyon heat in the afternoon that regularly tops 100°F. This page shows the first 16 hours, 5 AM to 9 PM, at four points along the course. Official site: wser.org.

Your own runs, any day

Open a route in Route Forecast and choose Run for the weather along it at your pace, what to wear, and on warm days how much the heat will slow you. Open a route · Heat pace calculator · What to wear running

Questions

What’s the weather forecast for the Western States?

The race-day forecast for the course appears on this page from about 16 days before the race, with the temperature at the start and along the course, dew point, how much the heat is likely to slow you, wind and rain. Until then the page shows the weather on June 26 in each of the past ten years.

What is the weather usually like at the Western States?

See the table on this page: the temperature at the start, the high, dew point, wind and rain on June 26 for each of the last ten years, with the typical, coldest and warmest starts.

What should I wear for the Western States?

Dress for about 15–20°F warmer than the forecast once you’re racing, and bring throwaway layers for the wait at the start. From 16 days out this page lists what to wear for the forecast; the what-to-wear-running calculator covers any conditions.