Deciding When to Visit
Denali is a land of extremes. Winters can be harsh, though starkly beautiful. Summers are short, packed full of intense activity for animals and humans alike. Spring is so brief that a matter of days can be the difference between hillsides looking drab and brown versus lush and green. Fall is equally brief, with tundra plants changing from green to brilliant reds and oranges, and then fading back to brown a week later.
Whether you plan to visit in summer, winter or the "shoulder seasons" between the two, there are many adventures to be had here.
For a visitor to Denali, the summer is when most services and activities are possible, and is when access into the park is easiest. The "core" season runs June 8 – mid-September each year, with some bus options available both before and after those dates. Mid-June to mid-August also sees the largest number of visitors to the park.
Expect the land to turn from brown to green in just a few days, at the end of May or beginning of June—depending on how mild the weather is. Wildflowers begin to bloom in early June, and can be seen until late July. Most flowers have gone to seed by early August, making way for a variety of berries and fall colors. By early August, tundra plants at high elevation will change color first; brilliant reds, oranges and yellows march downhill into the valleys, where trees change color in turn by early September. By then, the mountains will be brown again, if not blanketed in fresh white snow.
Animals are at their most active and visible from May to September, as they squeeze in as much living (and eating) as they can before the onset of another cold winter. Mosquitoes, too, are active in early summer, although by early August they have disappeared from all but the wettest parts of the park, like Wonder Lake.
The days are also at their longest in summer, with the solstice in late June offering over 20 hours of daylight. The summer sun provides so much light, the Aurora Borealis isn't seen until late August. As daylight hours rapidly decrease in the fall, chances of seeing the northern lights increase.
While snow can fall even in summer, snow that arrives in September tends to stay rather than melt away. Winter announces its arrival not just with snow, but with extreme temperatures and diminishing sunlight. Access into the park and services offered are limited between late September and late April, though self-sufficient folks will find plenty to do in winter. Temperatures can drop to -40°F (-40°C) and on the winter solstice—just before Christmas—the sun is above the horizon for less than four and a half hours.
