Alaska (Juneau)
USA · North America
The best time to visit Alaska (Juneau) is May, June, July, August, and September. In summer, daytime highs average 17°C (63°F), with peaks around 24°C (75°F); in winter, nights average -2°C (28°F), dropping to around -12°C (10°F) on the coldest. All climate data are based on historical monthly averages (2005–2025) to help you plan the optimal travel time.
Alaska (Juneau) – What you should know
Juneau is the capital of Alaska, and it can only be reached by ship or plane: no road leads out of the city. It lies in the Inside Passage rainforest between mountains and the Gastineau Channel, and the climate is cool and wet. From May to September daytime highs are 13 to 17°C (55 to 63°F), in July 17°C (63°F) on average and around 24°C (75°F) on the hottest days. Rain is still comparatively light in May and June at just under 100 mm (3.9 in) across about ten days, and clearly heavier in autumn, with 230 mm (9.1 in) in September across 18 days.
The main attractions are glaciers and whales. The Mendenhall Glacier lies about 20 km (12 mi) from downtown, and in summer humpback whales and orcas can be watched off Juneau. The sea is 13 to 14°C (55 to 57°F) in July and August, so water sport here means kayaks, not swimming holidays. Because of the northern latitude the days are long in June, but sunshine still drops to only 4 to 6 hours a day, since cloud is the rule. In May the sun is out most, at 7.5 hours a day.
From October to April Juneau suits travellers looking for quiet and a winter mood, but with a limited offer: daytime highs in winter are 1 to 4°C (34 to 39°F), in the coldest nights about -12°C (10°F), and the days are short, with under one hour of sunshine in January. Most cruises run from late April to early October. Compared with Ketchikan, Juneau is drier, compared with Skagway clearly wetter, and with the glacier it offers a day trip straight from the port.
Climate Overview
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Ø day, range from coolest to warmest dayØ dayrange | 2° (36°)-8– (18–)7 (45) | 2° (36°)-6– (21–)8 (46) | 4° (39°)-3– (27–)9 (48) | 9° (48°)3– (37–)15 (59) | 14° (57°)7– (45–)22 (72) | 16° (61°)10– (50–)25 (77) | 17° (63°)12– (54–)24 (75) | 17° (63°)11– (52–)23 (73) | 13° (55°)9– (48–)18 (64) | 9° (48°)4– (39–)13 (55) | 4° (39°)-3– (27–)9 (48) | 2° (36°)-6– (21–)7 (45) |
Ø night, range from coldest to warmest nightØ nightrange | -2° (28°)-13– (9–)4 (39) | -2° (28°)-12– (10–)3 (37) | -1° (30°)-9– (16–)3 (37) | 2° (36°)-3– (27–)6 (43) | 7° (45°)1– (34–)10 (50) | 10° (50°)5– (41–)13 (55) | 12° (54°)8– (46–)13 (55) | 11° (52°)7– (45–)14 (57) | 9° (48°)3– (37–)12 (54) | 5° (41°)-2– (28–)9 (48) | 0° (32°)-8– (18–)5 (41) | -1° (30°)-10– (14–)4 (39) |
☀️Sunshine | 1h UV 1 | 3h UV 2 | 4h UV 4 | 6h UV 5 | 8h UV 6 | 6h UV 6 | 5h UV 5 | 5h UV 4 | 2h UV 3 | 3h UV 2 | 3h UV 2 | 2h UV 1 |
🌊Water Temp | 6° (43°) | 5° (41°) | 5° (41°) | 6° (43°) | 8° (46°) | 11° (52°) | 13° (55°) | 14° (57°) | 13° (55°) | 11° (52°) | 8° (46°) | 7° (45°) |
🌧Rain Days | 16d176mm (6.9") | 11d108mm (4.2") | 11d90mm (3.5") | 11d94mm (3.7") | 10d96mm (3.8") | 10d103mm (4.0") | 13d134mm (5.3") | 15d175mm (6.9") | 18d229mm (9.0") | 17d219mm (8.6") | 16d165mm (6.5") | 14d155mm (6.1") |
Best travel timeØ = average · small figures = range: coolest–warmest day / coldest–warmest nightClimate data 2005–2025 · Source: ERA5 + station data
The travel year in Alaska (Juneau)
November – April
The quiet season: the cruise ships are gone, days are short and the sky is mostly grey. Snow falls in the mountains, while in town wet weather alternates with frost. Visitors now see the Alaska of the locals, with winter sports, a chance of northern lights on clear nights and empty streets.
May – June
Spring arrives with long days and the sun, which breaks through most often in May. The first cruise ships dock and humpback whales return to the waters off town. The Mendenhall Glacier sits in fresh green, and prices are still gentler than in high summer.
July – August
High summer in Juneau: long days, a full harbour every day, and whale-watching boats leaving by the hour. It is mild but rarely properly warm, and cloud comes with the territory. Salmon run up the rivers and bears appear along the creeks.
September – October
The rain returns, the deciduous woods turn yellow and the cruise season ends. The town grows quieter, the salmon runs wind down and the first snow reaches the peaks. Those who bring a rain jacket and patience find low prices and dramatic cloud moods.
Events & Festivals
April
- Alaska Folk Festival· early April
Since 1975, this free festival has turned downtown into one big week-long jam session with musicians from all over Alaska.
June
- Celebration· early June (every two years in even years, next edition 2028)
A four-day festival of the Tlingit, Haida and Tsimshian with dance groups, a procession and an art market — one of the largest cultural events in Alaska.
August
- Golden North Salmon Derby· early/mid-August (Fri–Sun)
This salmon fishing tournament has run every year since 1947, over three days in the waters around Juneau.
Frequently Asked Questions
- When is the best time to visit Alaska (Juneau)?
- The best time to visit Alaska (Juneau) is May, June, July, August, and September. These months offer the most favourable combination of sunshine, temperatures, and low rainfall.
- How warm does it get in Alaska (Juneau)?
- In summer, daytime highs in Alaska (Juneau) average 17°C (63°F), with peaks around 24°C (75°F); in winter, nights average -2°C (28°F), dropping to around -12°C (10°F) on the coldest.
- How much rain does Alaska (Juneau) get?
- Alaska (Juneau) has a relatively even rainfall pattern with an average of 14 rain days per month. The driest months are March, April, and May.
- How warm is the water in Alaska (Juneau)?
- Water temperature in Alaska (Juneau) ranges from 5°C (41°F) (March) to 14°C (57°F) (August). That makes the sea cool for swimming all year round.
Best Travel Time by Vacation Type
🏙️
City Trip
Pleasantly mild, not too hot
JunJulAug
