This is The Best Time to Visit Boulder (And Worst)

Looking for the best time to visit this Colorado mountain town known for its Flatiron mountain skyline and outdoor culture?

Well, I’ve done some digging (and, after my 2 year van life adventure across the West, I’ve got a bit of experience under my belt) to find out the best times to visit this gem of a city. That, plus making the mistake of going in the middle of the winter with limited clothing options.

Boulder is an all-year-round haven, but like Salt Lake City with its epic ski conditions in winter, Boulder has its prime times too. The weather in Boulder swings from pleasantly warm summers to brisk, snow-kissed winters. So, let’s break down the visitor seasons in Boulder:

• Best Season: April to June and September to November
• Peak Season: June to August
• Off-Peak Season: December to February

Ready for the specifics of each season in Boulder, including must-see events and typical weather conditions? Whether you’re planning a Boulder day trip or a more extended stay, from rock climbing and hiking to drinking local craft beers, these are the perfect times to visit Boulder.

Best Time to Visit Boulder

Best Time of Year to Visit

Hands down, the best time to go to Boulder is during the late spring and early summer, between May and June. This season gifts you the perfect weather for hitting the trails or enjoying local cafes under the warmth of the sun, minus the heavy tourist traffic. You get the full Boulder vibe, with blooming nature and lively streets.

Best Time for Good Weather

For the best weather, aim for late spring to early fall, around late May through early September. During this period, the daytime highs will settle between 70°F and 85°F, perfect for all outdoor activities under sunny, blue skies. At this elevation, nights still can cool off pretty severely.

Best Time to Avoid Crowds

To dodge the crowds, go during the shoulder seasons: late spring and early fall (September to October). You’ll find fewer people around because you’re sneaking in just after the height of the ski season and right before or after the summer vacationers swarm in.

Cheapest Time to Visit

The cheapest time to go is during its off-peak season, which falls in winter, from December to February. I went during this season, and the trouble is that many of the trails are completely snowed out and closed off. 

However, the scenery is absolutely gorgeous, and accommodation rates plummet as much as 50% compared to peak summer prices, making it a steal for those willing to brave the colder weather.

Worst Time to Visit Boulder

Boulder is blessed with a lot of sun and relatively mild days. It’s a great all-year-round place, but during the heat of mid-summer, specifically July and August, the city swelters under temperatures that can climb into the 90s. Plus, it’s the peak season, so expect crowded trails, full patios, and booked-up accommodations. 

Otherwise, if you’re not into snow sports, the dead of winter does limit your activities and options. Though it’s a magical time, with snow-covered mountains and festive holiday vibes, this may not be the season for you if you’re looking for more outdoor adventure.

Seasons of Boulder

Spring (March to May)

Spring in Boulder welcomes adventurers and nature lovers back into its open spaces. The Flatirons, iconic to Boulder’s skyline, have a lingering dust of snow on their tops, while the trails at their feet are ready for hiking. 

Wildflowers start to dot the landscape with color, and the local wildlife becomes more active. You can hit the Colorado trails in the morning with a light jacket and, by afternoon, be chilling in a t-shirt at a local brewery’s patio. 

Temperature-wise, the average ranges from the high 50s to mid-70s. It’s warm enough for outdoor fun but not so hot that you’re seeking shade every five minutes. Plus, the city isn’t swamped with visitors yet.

Key Events: 

• Boulder International Film Festival (March): A four-day event featuring over 55 films from around the world.
• Boulder Arts Week (April): A nine-day celebration of Boulder’s vibrant arts scene, with over 100 events and everything from live music and dance performances to visual arts and interactive workshops.
• First Sip Boulder (April): A month-long celebration of Boulder’s craft beer scene, with special events and promotions at local breweries.
• Tulip, Fairy & Elf Festival (April): spring with over 15,000 tulips in full bloom, live entertainment, and children’s activities. 
• Boulder Creek Festival (May): A three-day community event with live music, a carnival, an art show, and food vendors.

Summer (June to August)

Summer in Boulder is when everything’s in full bloom, the days stretch longer, and daytime highs hover around the mid-80s to low 90s. The days are usually always sunny. 

The Flatirons serve as a picturesque backdrop and a playground for hikers and climbers. And if the heat gets too much, there are numerous creeks and lakes to take a refreshing dip in.

Summer in Boulder is also packed with cultural festivities, from outdoor concerts and movie nights to local farmer’s markets.

Summer marks Boulder’s peak tourist season, so the city is at its liveliest. Dining al fresco becomes a daily ritual, and patios and rooftops are filled with locals and visitors alike.

Key Events: 

• Boulder Jewish Festival (June): A day of Jewish culture filled with music, food, and community.
• Colorado Shakespeare Festival (June to August): To be, or not to be… Brush up on your Shakespeare with outdoor performances.
• Boulder Taco Fest (August): Join the fiesta with a day celebrating all things tacos, featuring live music and taco vendors from around the city. 
• Great Boulder Duck Race (August): Cheer on your rubber duck as it races down Boulder Creek during this quirky and beloved event.

Fall (September to November)

From September through November, the city undergoes a magical transformation into striking fall foliage colors. Temperatures range from the high 70s in early September to the chilly 40s by late November, so layer up for the outdoors.

The aspen trees shine with their brilliant yellows and golds, making hiking or biking through Boulder’s numerous trails absolutely incredible. Go to Chautauqua Park if you’re at all into photography.

For adventurous souls, fall is the perfect time for rock climbing. The cooler temperatures provide ideal conditions for tackling the famous Boulder Flatirons or exploring the canyons.

Festivals continue with a focus on local harvests, showcasing Colorado’s rich bounty with food and beer festivals that celebrate the season’s end. 

Key Events: 

• Downtown Boulder Fall Fest (September): A three-day street party with live music, a beer garden, and local vendors.
• Boulder Burgundy Festival (October): An annual celebration of all things Burgundy wine featuring tastings, seminars, and dinners at some of Boulder’s best restaurants. 
• Munchkin Masquerade (October): A family-friendly Halloween event with trick-or-treating on Pearl Street Mall.

Winter (December to February)

Boulder’s winter is a wonderland of deep, deep snow. From December to February, temperatures hover around the 20s to 40s Fahrenheit, but at least it’s under mostly clear, blue skies.

The snow-capped Flatirons are great for snowshoeing and cross-country skiing, and some trails are open to winter hiking. Eldora Mountain Resort, just a short drive away, is the go-to spot for skiing and snowboarding.

The city lights up with holiday spirit, starting with the annual Lights of December Parade. Downtown Boulder twinkles with festive decorations, and local shops and restaurants go all out to create a warm atmosphere while holiday markets pop up.

Key Events: 

• Ullr Fest (December): Ullr Fest is where Boulder pays homage to the Viking snow god himself. Expect quirky traditions, bonfires, and parades.
• Freezie Fest (December): A family-friendly winter celebration with ice skating, live music, and more on the Pearl Street Mall.
• WinterFest (January):  A two-day music festival at the Fox Theatre showcasing local and national talent.
• Wintersköl (January): The annual Aspen winter festival that includes a snow sculpture competition, a canine fashion show, and more.
• Ouray Ice Festival (January): It might be a bit of a drive from Boulder, but it’s worth mentioning. Ice climbers from around the globe gather to show off their gravity-defying skills on frozen waterfalls. 
• Winter Craft Beer Festival (February):  A celebration of Colorado’s craft beer scene with over 50 breweries participating.

Boulder Weather By Month

This is a detailed month-by-month overview of Boulder’s average high and low temperatures, along with precipitation and snowfall data:

Month	Average High	Average Low	Precipitation (days)	Snowfall (inches)
Jan	44°F	23°F	0.8d	2.2″
Feb	47°F	25°F	1.2d	2.4″
Mar	55°F	31°F	2.5d	2.5″
Apr	61°F	37°F	5.5d	1.9″
May	70°F	46°F	8.1d	0.3″
Jun	81°F	55°F	6.5d	0.0″
Jul	86°F	60°F	8.2d	0.0″
Aug	84°F	58°F	7.4d	0.0″
Sep	76°F	50°F	4.7d	0.2″
Oct	64°F	39°F	3.3d	1.4″
Nov	52°F	30°F	1.7d	2.4″
Dec	43°F	23°F	0.8d	2.8″

Before you Close That Tab…Where to Next in Colorado?

I’ve vanlifed south to the north all of Colorado in the dead of winter to early spring. Let me tell you, it was cold, but turn on that buddy heater, and let’s hit the slopes. If you’re looking for more information on Colorado, check out these other destination itineraries.

• Perfect One Day In Mesa Verde National Park Itinerary
• Perfect One Day In Black Canyon Of The Gunnison Itinerary
• Unbeatable One Day In Rocky Mountain National Park Itinerary
• One Day In Boulder Itinerary: What Not To Miss On A Day Trip
• Perfect One Day In Denver Itinerary For First-Timers
• Perfect One Day In Great Sand Dunes National Park Itinerary

MY FAVORITE TRAVEL RESOURCES

✈️ Find amazing guided tours and experiences with Viator to maximize your time! 🏘️ Plan ahead and secure your accommodation with Booking.com in advance. 🧾 Rent a car with Discovercars in advance and get the best prices for your day trip adventures.