It’s certainly a unique day when iRunFar publishes an article about a race’s weather forecast.
Have we mentioned the weather in previews, interviews, and race results? Countless times. But the forecast for this year’s Western States 100 is looking special, with a high of 73 degrees Fahrenheit on Saturday, June 27, according to Wunderground as of late Thursday afternoon. That’s 17 Fahrenheit (F) cooler than the average race-day high.
While not the absolute hottest spot on the course — that title goes to the bottom of some of the canyons — the town of Auburn, California, is the exemplary spot where the race’s official high temperature is recorded every race Saturday. The average high to date is 90F.
Ellie Greenwood clearly having a bit of fun in Robinson Flat on her way to setting the then course record at the 2012 Western States 100. Photo: iRunFar/Bryon Powell
The two years with the lowest high temperatures to date were 66F in 1991 and 71F in 2012.
In 1991, Tom Johnson set the men’s course record and became the first person to break 16 hours — 15:54:05 — on the full 100.2-mile course, while Ann Trason won for the third-straight time in 18:29:37.
In 2012, Timothy Olson became the first person to beak the 15-hour barrier in running 14:46:44, while Ellie Greenwood took 72 minutes off Trason’s later 1994 course record by running 16:47:19. This is the sort of year where myself, Andy Jones-Wilkins, and then Assistant Race Director Craig Thornley were all up in the cold drizzle at Robinson Flat telling one another, “I sure wish I had a bib!”
Timothy Olson setting the then course record at the 2012 Western States 100. Photo: iRunFar/Bryon Powell
The only other year with a high below 80F was 2005, with a high of 78F. I ran it. It was dreamy. It was only my second 100 miler, but I only ever managed to run six minutes faster in another 100 miler. In other words, a sub-80F day at Western States is the stuff of dreams.
The current men’s course record of 14:09:28 was run by Jim Walmsley on a day with a high of 83F in 2019. Courtney Dauwalter ran the women’s course record of 15:29:33 in 2023, which saw a high of just 80F.
Jim Walmsley on his way to setting the current course record at the 2019 Western States 100. Photo: iRunFar/Meghan Hicks
Having followed the front of the fields in 20-plus Western States, I’ve seen that the intuitive view on weather holds. Cooler weather leads to less carnage. Even if it takes a while, hot days eventually take their toll and blow the field apart with plenty of front-of-the-field DNFs. I don’t want to get into the realm of hyperbole, but the men’s field and women’s field are strong and deep. The inherent depth at the front, in combination with a much lower blow-up rate and less heat limitation on individual performances, likely means hard racing for the win. That’s the sort of competitive situation that happened at the London Marathon earlier this year, when two runners broke two hours and a third went under the marathon world record.
Courtney Dauwalter setting a new course record at the 2023 Western States 100. Photo: iRunFar/Meghan Hicks
And it’s not just fast times at that front that are likely. Of the five years with large fields* with over 80% finishing rates, you have four years with lower high temperatures of 71F (2012), 80F (2023), 82F (2011), and 83F (2019), along with the outlier year of 2018, which topped out at 98F.
Let’s close out with a few observations that go beyond the high in Auburn on Saturday. Long-time followers of the race might be familiar with the term “pre-baking,” which refers to what can happen in the race’s lower canyon sections when it’s particularly hot and sunny in the days leading up to the event, when the rocks absorb heat and become their own thermal engines. That’s important in two ways, as those canyons can often top out at 10 or more degrees Fahrenheit over the official high, and that pre-baking can lead to much earlier high heat in the canyons for the front-runners and persistent heat throughout the night for the rest of the field. Well, the current forecast includes some clouds in Auburn on both Friday and Saturday mornings, along with quite moderate pre-race temperatures in the low-to-mid 80Fs. What’s more, the forecast low for Saturday night is a dreamy 53F.
Let’s get excited! This is the stuff of PRs, and probably also course records!
A very excited Bryon Powell and Andy Jones-Wilkins in the cold drizzle of Robinson Flat during the 2012 Western States 100. “Puffy jackets? At Western States!!” Photo: iRunFar/Bryon Powell
* In other words, if you exclude the pioneering years of 1974 and 1976, where the single starter finished each year.
