ジュノーの月別の天気

Juneau forum regulars describe January bluntly: nighttime readings average around 20°F, conditions that can run rainy, snowy, icy, windy or cold and sunny in no particular order. The real obstacles for a winter visit aren't just the weather — poor road conditions at times, not much daylight, not many tourist activities available — and virtually all visitor attractions closed except the Alaska State Museum. What does stay open: a downhill ski resort, rentable snowshoes and cross-country ski trails, and the Alaska Club's heated pool for anyone wanting an indoor break from the cold. Regulars are consistent this only works if you're genuinely prepared for harsh weather and interested in winter outdoor activities rather than the standard summer glacier-and-wildlife itinerary. Our record: -1°C days, -4.3°C nights, 297.5mm of precipitation, 21.8 rain days and 183.8cm of snow — genuinely severe winter weather, matching the “harsh, most tourism closed, real snow sports instead” read.

Juneau forum threads describe February as genuinely variable and often described by posters as pretty miserable - rain, snow, wet snow, icy wind or occasionally cold and clear, with no single dominant pattern to count on. Posters were direct that the month rewards flexibility: warm, waterproof layering and a willingness to adjust plans day to day matter more than any specific forecast. A practical note repeated across threads: Alaska's state Legislature convenes in Juneau in February, pushing hotel prices up during what would otherwise be a quiet season. For those hoping to catch the Northern Lights, posters were candid that Juneau's frequent cloud cover makes it an unreliable spot for aurora viewing, though not impossible on a clear night. Snowshoeing toward Mendenhall Glacier or Eagle Beach was recommended as a solid way to make the most of the conditions.

Regulars are specific that early in this month can bring a genuine winter relapse, fresh snow falling all the way down to sea level and putting tours like Glacier Bay or helicopter flightseeing on hold, a real contrast to how settled May becomes just weeks later. Our row backs that cold, still-wintry read, 9.6C over 0.4C nights feeling -2C, with a heavy 163.4mm of rain across 17.6 days and a real 17.8cm of snow. Regulars are consistent that layered clothing plus proper rain gear, boots, gloves and a hat cover most of what this month can throw at a visitor, since conditions can swing from a mild, clear day to a genuine snow event within the same week. The record: humidity 80 percent, 7.7 hours of sun, a 9.8 kph wind and AQI 40.

Regulars are consistent on one rule regardless of the forecast: always bring proper rain gear to this part of Alaska, since even a visitor who caught a genuinely beautiful stretch one year is quick to add that the same week the year before was a washout. Our row backs the wet reality, 175.7mm of rain across a striking 15.4 days, alongside cool temperatures, 14.5C over 5.1C nights feeling 2C, and a trace of late snow, 2.6cm. Regulars pushing toward late May specifically say it can bring some of the season's best weather, so the back half of the month is worth favouring if the dates are flexible. Layering is the standard advice on top of the rain gear, since the temperature swings enough within a day to matter. The record: humidity 82 percent, 8.9 hours of sun and AQI 37.

Juneau measures rain on 222 days of an average year, and the forum's most useful correction is about the kind: this is drizzly English rain rather than a Florida downpour, so it can rain any day without ever being an all-day soaking. Our row gives 164.2mm across 16.7 precipitation days in June. Early June can be genuinely cold and windy, with port temperatures ranging from the high 60s Fahrenheit down to the 40s or 50s, which our row averages at 18.5C over 9.6C. Excursions rarely cancel for rain - the outfitters hand out gear - and the packing list is layers, rain gear, and a hat and gloves for any glacier day. The record: humidity 81 percent, 9.6 hours of sun and 18.1 hours of daylight.

Juneau's forum is blunt that Southeast Alaska's weather changes hour by hour and no one can guess it days out — rain is possible in port regardless of the season. Regulars' standard packing list: proper rain gear, layers including a fleece, and a t-shirt for the occasional warm afternoon in the 60s°F.

Regulars answer the question about August rain by reframing it: this is temperate rainforest, measurable rain falls on 222 days of the year, and the right expectation is cloud and drizzle with a sunny day as a bonus. They put the month near 59F with roughly a three-in-four chance of rain on any day, and our row agrees emphatically at 265.1mm across 17.8 days under 19.2C. What the weather does not spoil is the reason to come: the whale trips from May to mid-September find humpbacks essentially every time, with about a one-in-five chance of orcas. The cruise season runs to mid-September. Evenings darken by half past nine. The record: humidity 85 percent, 8 hours of sun and AQI 28.