The 2025 Outside Festival in Denver Was Electric. Here’s What You Missed.

At first, the breeze felt wonderful—a blast of chilly air to dull the afternoon heat.

It was Sunday, June 1, and I was standing at the entrance to Denver’s Civic Center Park, welcoming guests to the Outside Festival, clad in my sweat-stained volunteer t-shirt. In front of me, 15,000 or so guests swarmed the park. Some crowded the main stage to see indie folk singer Hazlett. Others rushed to the Denver Art Museum to catch former National Park Service director Chuck Sams III speak about the ongoing public lands battle. Others still mingled around booths for The North Face and REI.

People fanned themselves to cool off, others sat under trees or tents. And when the light wind began to blow, everyone felt a momentary respite from the baking sunshine.

And then the wind got much stronger.

I looked to the west. Dark clouds from over Colorado’s Front Range were speeding toward Denver, a whirling mass of grey and green. It looked like the scene in Independence Day when the alien spacecraft is about to arrive.

Anyone who has lived in Colorado for more than a few years knows this scene—it’s the precursor to the thunderstorms that roll across our state almost every afternoon in June through August. The storms blow in like hurricanes, drop inches of water, light up the sky with bolts of electricity, and then vanish, usually within an hour.

You don’t want to be on the side of a fourteener when one arrives. But if you’re out camping, you can duck inside your tent, read a chapter of your book, and then emerge to pristine conditions. These storms are why Coloradans overuse the cliche Don’t like the weather? Just wait 5 minutes. 

But what happens when a thunderstorm descends on 15,000 concertgoers in a city park? As it turns out, something kind of magical.

Big Crowds, Bigger Ideas

Last year we debuted the Outside Festival and Summit in downtown Denver, and the event—a blend of music, films, celebrity speakers, outdoor films, and a celebration of outdoor recreation culture—surpassed our wildest expectations. The Outside Summit attracted a smattering of industry leaders and brands. About 18,000 people attended that inaugural festival over the two days. They danced to up-and-coming acts like Say She She, queued up to meet celebrity speakers like Diana Nyad and Shaun White, and packed an auditorium to check out the lineup of outdoor films.

For 2025 our goal was to make the weekend even bigger, and for the most part, we succeeded, drawing nearly 35,000 people to Denver’s Civic Center Park. Diana Nyad came back, alongside magician David Blaine, climber Alex Honnold, surfer John John Florence, and two former National Park Service directors (among others).

We added  Outside Ignite, a Shark Tank-like pitch competition for outdoor innovators (Kyle Siegel of Raide Research Packs won the $100,000 grand prize). And at the Outside Summit, attendees got to meet Netflix co-founder Reed Hastings and hear Hipcamp founder Alyssa Ravasio talk about launching a start-up.

I attended all four days, and based on my own highly unscientific survey of vibes and vibes alone, I’d say that the marks we earned were positive.

As I wrote last summer, this event represents an experiment for those of us who work for Outside’s parent company, Outside Inc. For two days, editors, advertising reps, marketing types, and other employees cosplay as event producers, working alongside a professional event production company, Groundswell, which manages the event. We put down our keyboards and spreadsheets and pick up walkie talkies and nylon zip ties. Instead of selling ads or writing stories, we do crowd management.

So you can understand my concern when I saw the storm clouds barreling down on the park. I saw one lightning flash, then another. Um, what are a bunch of editors and advertising salespeople going to do about that I wondered.

Flash of Lightning, Driving Rain

The emergency training I’d gotten prior to the event (that was reinforced constantly by the event managers) echoed in my brain. In the case of extreme weather, help people to an exit, point them to shelter, and clear the park. 

And just like that, the drops began to fall. Hazlett wrapped up his set, and the giant screens adjacent to the stage beamed a message. We are temporarily halting the festival due to weather. Please seek shelter. 

Gentle rain quickly turned into a driving downpour. Lighting crackled overhead. Wind gusts toppled trash cans and blew them across the park as if they were Kleenex.

I looked across the park and saw volunteers shuffling the public toward the McNichols building on the north side of the park, and also into the Denver Public Library and the Denver Art Museum. I ran to one of the emergency exits and flung it open, and began pointing attendees to the Denver Post building on the northeast side of the park.

It’s impressive how quickly 20,000 people can move after a loud thunderclap or two. And within ten minutes or so, the park was a soggy and blustery—but mostly empty.

A mom with her kids ran by me toward the exit. “Do you think we will come back?” she asked. Guessing that the tempest would end within the hour, I told her to find shelter nearby, but to stick around.

An Impromptu Performance

What do you do to pass the time during a Colorado thunderstorm? Get creative. That was the mantra for the 45 minutes that elapsed during our hiatus.

I cowered under a white tent near the the festival entrance. But every few minutes, my walkie talkie pinged to life with updates from other buildings. As it turns out, people were using the break for impromptu entertainment.

Inside the McNichols Building, one of the performing acts, Brothers of Brass, began playing to the crowds standing shoulder to shoulder in the main hall. Someone texted me a video of the dance party.

At the Denver Art Museum, comedian Eeland Stribling, who was on a panel of outdoor comics, picked up the microphone and performed a comedy set for the soggy guests packing the auditorium.

I looked out from my shelter and saw a few hearty souls sitting in the rain despite the evacuation orders, letting themselves get drenched.

And then, like so many other Colorado thunderstorms, this one simply blew on, to the east, and disappeared.Sunshine chased off the last fragments of clouds. People emerged from their shelters. And before I knew it, a massive queue formed at the main entrance. Thousands of people had stuck around.

More Cowbells

Above: scenes from the rain delay at the 2025 Outside Festival

It took us about 30 minutes to open up the tents, set up the toppled trash cans, and ready the park for visitors. At one point I strolled along the massive line to get in to tell people that we’d soon open.

I half-expected to be pelted with trash or beer cans for being the messenger of a delayed festival. But no—I was met with good vibes and high fives. Yes, some folks were still soggy from the downpour, but people were ready to get back inside and party.

When I think back to the 2025 Outside Festival now, the moment I always come back to is this. When the park was finally ready, the other volunteers and I opened the gates and welcomed everyone back in to see the remaining three bands: Waxahatchee, Trampled by Turtles, and Lord Huron.

Several dozen Outside staffers and volunteers crowded the entrance. Someone banged a cowbell. Everyone cheered. As the thousands of guests re-entered the park, they high-fived us, hugged us, and gave us fist bumps. Yes, some of the embraces were wet. We didn’t care.

The midday heat was gone, chilled down by the rain storm. The sun began to set above the Front Range as people strolled out to the main stage. The opening bluegrass bars of a Waxahatchee song echoed through the park, and people began to dance. It was just another perfect evening in Denver.

I heard someone say: “Well, that’s Colorado for ya.”

Articles editor Frederick Dreier is no longer seeking shelter from the storm.