Denver

Here's the thing about Denver: everyone talks about the 300 days of sunshine, but what they don't mention is that the city sits at 5,280 feet, which means the sun hits different — you'll burn faster and feel temperature swings more dramatically than you'd expect. The annual average high is around 18.8°C (66°F), which sounds pleasant until you realize that's dragged down by brutal January and February. If you're actually planning to enjoy yourself outdoors, you want April, June, September, and October. These months aren't just "good" — they're the ones where Denver actually feels like the outdoor paradise locals keep bragging about.

April is the wildcard: highs climb to around 16–18°C (60–64°F), but you get those rare, warm afternoons where you suddenly understand why people moved here. Wildflowers start showing up in the foothills, and the city isn't yet overrun with summer tourists. June is different — warmer (highs around 27°C/81°F), drier than you'd expect (only 429 mm falls annually in Denver, which is genuinely dry), and the light lingers until 9:15 pm. September is the sleeper pick: crowds vanish, highs drop back to 25°C (77°F), and you get that perfect "shirt-sleeves in the morning, sweater by evening" rhythm. October is the golden hour literally — aspens turn in the mountains an hour away, the air gets crisp (highs around 18°C/64°F), and the city feels like it's taking a breath before winter.

What should you avoid? January through March is when Denver gets its rare snow dumps, and while the city's usually cleared by afternoon, the whole vibe feels closed in. July and August are hot (highs often hit 28–29°C/82–84°F) and crowded with families on summer break — parking gets brutal, restaurant waits stretch, and you're sharing trailheads with half of Texas. November gets gray and unpredictable, and by December, holiday crowds and potential early snow make it feel chaotic rather than festive.

Worth noting: Denver's climate has shifted slightly over the past decade. Spring arrives earlier now — April feels more reliably warm than it did in 2015. Summers are holding heat longer into September. For 2026, expect slightly warmer-than-normal temps in your best months, but nothing that breaks the pattern. The 10.3 average hours of daily sunshine is real, so even in your "off" months, you're getting decent light.