Boulder is rewriting the record books this summer—and not in the fun way.

As of mid-August 2026, Boulder had recorded 23 days at or above 95 degrees, setting a new calendar-year record. The city had also reached 100 degrees six times, tying the annual record set in 1954, while 40 days at or above 90 degrees had already accumulated.

The most startling number came on August 3, when the Boulder Municipal Airport climate site reached 104 degrees. That tied the location’s all-time high and established a new August record. The latest totals were compiled by BoulderCAST from local climate observations, underscoring just how unusual this summer has become.

For hikers, runners and dog owners, the message is simple: Boulder’s outdoors are still open, but the daily routine needs to change.

Best Shaded Boulder Trails During Extreme Heat

When the sun is relentless, canyon walls, tree cover and an early start can make a major difference.

Anne U. White Trail remains one of the coolest nearby choices. Its narrow canyon, creek crossings and mix of cottonwoods, willows and evergreens provide more protection than Boulder’s exposed foothill routes. Dogs are permitted but must remain leashed.

Anne U. White Trail

Shadow Canyon offers substantial shade once hikers enter the canyon, but reaching it requires crossing more exposed terrain. This is a demanding outing, not a casual escape from the heat, so begin near sunrise, carry ample water and turn around early if temperatures climb quickly.

Gregory Canyon provides tree cover along portions of the route while keeping hikers close to classic Flatirons scenery. Bear Canyon and the forested sections of Betasso Preserve are also useful alternatives. At Betasso, dogs must be leashed, and hikers may prefer Wednesdays and Saturdays, when bicycles are prohibited.

Hiking towards Gregory Canyon

For a shorter, gentler outing, the Boulder Creek Path offers convenient access to shaded sections beneath mature cottonwoods. Bobolink Trail can also work early in the day, although parts of it remain exposed.

Before leaving home, check the city’s current OSMP closures and advisories. Start before 8 a.m.—earlier on triple-digit days—and avoid strenuous afternoon outings. Carry more water than usual, use sun protection and remember that Boulder’s dry air can increase moisture loss even when sweat evaporates quickly.

For more ideas, see AboutBoulder’s guide to Boulder’s best shaded dog-friendly trails.

How to Keep Your Dog Safe in the Heat

Dogs regulate body temperature primarily through panting and can develop heat illness rapidly. Older dogs, puppies, flat-faced breeds, overweight dogs and animals with heart or respiratory conditions face added risk.

Schedule walks for early morning or after surfaces have cooled in the evening. Before stepping onto pavement, press your hand against it; if the surface feels uncomfortably hot, choose grass, shade or another route. Even when the ground seems manageable, a strenuous hike may still be unsafe because air temperature, direct sun and exertion all add heat.

Bring drinking water and a collapsible bowl rather than relying on creeks. Offer small amounts frequently and do not assume that creek water is safe for a dog to drink.

Warning signs include frantic or excessive panting, heavy drooling, weakness, vomiting, diarrhea, confusion, abnormal gum color, stumbling or collapse. If these appear, stop activity, move the dog into shade or air conditioning and begin cooling with cool—not ice-cold—water. Wet the body, especially the underside, and use moving air when available.

Heatstroke is an emergency. Contact a veterinarian immediately and transport the dog for care, even if it begins to appear better. The American Veterinary Medical Association’s warm-weather guidance also stresses that pets should never be left in a parked vehicle.

Dog rules vary across Boulder’s trail system, and seasonal leash restrictions begin on portions of several OSMP trails on August 15. Check the posted regulations before every outing and leash your dog whenever wildlife, crowds or conditions make close control important.

Where to Cool Down and Recover

Boulder Creek can provide a refreshing place to sit beside the water, especially around Eben G. Fine Park, but moving water always carries hazards. Creek access and tubing restrictions can change with flow, water quality and emergency orders, so verify current conditions before entering.

Eldorado Springs Pool

The historic Eldorado Springs Pool is another option for a full reset. Its published summer schedule runs daily through Labor Day, but hours and availability can change, so check before driving over.

After any outdoor activity, prioritize water, electrolytes when appropriate, food and rest in a cool environment. Headache, dizziness, nausea, unusual weakness, confusion or fainting are signals to stop—not challenges to push through.

Boulder’s open space still offers relief and beauty during this extraordinary summer. The safest strategy is also the simplest: choose shade, start early, shorten the route, protect your dog and treat the hottest hours as recovery time. The trails will still be there when the temperature eases.

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