デンバーの月別の天気
デンバーを訪れるベストシーズンは5月、6月、9月です — 9月は90/100、最高29°C、雨の日3日。 ベストな季節は夏(6月〜8月)で、平均84/100です。
最も不向きな月は1月で、63/100です — 寒い、雨が少ない、空気がきれい。 1月を見る →
2026年9月更新 · ERA5再解析による気候平年値
周辺も含めて旅を計画するなら アメリカ合衆国旅行のベストシーズン →
デンバーDenver, United States🇺🇸 アメリカ合衆国 · ロッキー山脈 · 都市90
ベストな季節:6月〜8月(平均84/100) · 最も不向きなのは1月(63/100)
- 日中
- 29°C
- 夜
- 11°C
- 雨の日
- 3
- 日照
- 10.9 h
- 湿度
- 46%
- 日の長さ
- 12 h

デンバーの月ごとのようす
デンバーに最も合う旅のタイプでの100点満点の快適スコア、気候平年値による平均最高気温・雨の日数・1日の日照時間、そして混雑具合の目安です。
デンバーの年間イベント
祭り、自然の見どころ、祝日、そして注意したい季節 — 厳選し出典を明記しています。詳しくは各月のページで。
- 1月
- National Western Stock Show1月5日〜28日(例年)祭り
- 3月
- Denver March Powwow3月15日〜29日(例年)祭り
- 4月
- Red Rocks concert season4月1日〜11月5日(例年)オープン
- 6月
- Wildfire smoke and ozone6月15日〜9月15日(例年)要注意
- 7月
- Independence Day7月3日〜5日祝日
- Afternoon monsoon storms7月5日〜9月5日(例年)要注意
- 9月
- Great American Beer Festival10月10日〜11日祭り
- Aspen colour9月15日〜10月10日(例年)自然
- 10月
- Mountain ski season10月25日〜4月20日(例年)季節
- 11月
- Thanksgiving11月25日〜29日祝日
- 12月
- Christmas and New Year12月24日〜1月1日祝日
9月のデンバーの混雑
その場所自体の混み具合 — 学校休暇や大型連休、編集部がタグ付けした月、そして天気の良さによる人気の高さ。快適スコアには含まれません。
ピークの混雑Aspen colour、アメリカ合衆国のSummer break(推定)
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ピークの混雑混雑ショルダーシーズン閑散
デンバーへ行く前に知っておきたいこと
旅行者自身の旅行記から、実際の体験を原文へのリンク付きで引用しています。
健康
A traveler combining hiking and craft beer in Denver, sitting at exactly 5,280 feet (the actual 'mile high' elevation), passes along a widely repeated local rule of thumb worth taking seriously: one drink at altitude tends to hit like two would at sea level, since thinner air and lower oxygen levels amplify alcohol's effects faster than most visitors expect. He recommends pacing drinks more conservatively than usual on a first Denver visit specifically to avoid what locals call an altitude hangover, which can set in even after a modest amount if you're drinking at the same pace you would at home. He also notes hiking itself takes more effort here purely because of the thinner air - even a straightforward trail like the 6.5-mile Herman Gulch, with about 1,755 feet of elevation gain, felt tougher than a comparable sea-level hike he'd normally consider easy. Posters generally recommend drinking extra water and genuinely pacing both hiking and drinking slower than usual for the first day or two in Denver, letting the body adjust before pushing hard at either.
デンバーの旅行者の声
実際に訪れた人たちの声です — 通年のメモを先に、そのあと月ごとに並べています。
Denver forum threads describe January as genuinely hard to predict, with posters noting plenty of sunny days alongside real possibilities of bitter cold or, on the mild end, weather warm enough to eat lunch outside. Flight disruption concerns were addressed directly by posters, who pointed out Denver International Airport has only closed a couple of days in over a decade despite the city's snowy reputation, since the airport and I-70 corridor toward the ski areas are treated as critical infrastructure. Posters steered visitors away from January road trips given the real risk of sudden bad weather, but were positive about in-city activities, suggesting snowshoeing over hiking as the better-suited winter outdoor option for the month.
The fact that surprises visitors: "we often get more snow in spring than winter. Historically, March averages out to be the snowiest month in Denver, followed by April." What that does not mean is a snowy city — "snow typically doesn't stay on the ground for very long in Denver," and anyone coming to play in it is told plainly, "you will have to go to the mountains for snow activities," where "the snow at the higher elevations doesn't melt until mid-June." So March is a big-snowfall month that mostly melts on contact at 1,600m, and a reliable snow month an hour's drive up. Our record agrees on the totals — 28.8cm in March, more than any other month — alongside 10°C days and 9.8 hours of sun, which is the combination that melts it.
Denver-forum threads on May draw a sharp elevation line: the city itself is warming fast by this point, while the resort towns up in the mountains - Vail, Aspen, Breckenridge - are stuck in what regulars call mud season, the snow melting away without the ground being dry enough yet for summer trails. Anyone chasing actual snow is told to just drive a high mountain pass instead; above roughly 9,500 feet there's still plenty of it through mid-May, less likely after the 22nd as the month wears on. Down in Denver proper the record backs the warming trend: 22.2C days, 7C nights, 74mm of rain across eight days, 11.6 hours of sun, and a late 4.4cm of snowfall still possible early in the month before the city's own spring properly arrives.
June storms are routine here and regulars turn them into a rule rather than a warning: the mornings are sunny and dry, the storms build mid to late afternoon, so hike early and be heading down by noon. Most are scattered and brief, under half an hour, with perhaps one week a summer of something more persistent. At altitude a single spring or early-summer day can hold rain, thunder, freezing drizzle and snow on the high ground, which is why the timing matters more than the forecast. Our row is otherwise a dry, bright month: 30.7C days over 13.4C nights at 51 percent humidity, 45.5mm across 6.2 days and 13 hours of sun. The record: a 15.9 kph wind and AQI 47.
Regulars from humid climates like Atlanta and the Southeast consistently note that even when Denver's temperature matches what they're used to at home, the dry air makes it feel genuinely different, with cooler overnight temperatures providing real relief that a humid climate wouldn't give at the same daytime high. Our row backs the hot, dry read, 32.7C reading as 32C at just 49 percent humidity, over 15.3C nights, with rain minimal at 26.3mm across 5 days. Regulars are specific that afternoon thunderstorms are a real, near-daily possibility this time of year, brief but capable of disrupting an outdoor plan even on an otherwise scorching day. The record: 11.9 hours of sun, a 14.4 kph wind and AQI 46.
Denver's forum rates September among Colorado's most beautiful months — sunny, mild days in the 70s with chillier nights, especially once you head toward the mountains. Regulars flag that an early snow, however brief, isn't unheard of even late in the month, though it typically melts fast.
Regulars are blunt about the spread this month can produce: early October is generally the better bet, still holding some fall color at lower elevations, while late October swings unpredictably between an 80-degree Fahrenheit afternoon and a foot of snow depending on the year. Our row backs a genuinely wide range, 20.6C by day over a real 0C-feeling night, with a modest 18mm of rain across 3.3 days alongside a real 6.4cm of early snowfall. The standard advice from regulars is layering that can come off in full sun and go back on in shade or after dark, since the swing happens within a single day as much as across the month. Dry air keeps humidity down to 50 percent even on a cold day. The record: 9.4 hours of sun, a 14.7 kph wind and AQI 31.
地図のデンバーのカードから自分のメモを追加できます。