Rocky Mountain National Park’s 415 square miles encompass and protect spectacular mountain environments. Over 300 miles of hiking trails, wildflowers and wildlife.
Sweet spot months in Rocky Mountain National Park (RMNP) without the heavy summer crowds, open Trail Ridge Road and a good chance of nice weather are late May until early June or September after Labor Day (mid-week) until mid-October. However, snow is possible at both times. September is also great for wildlife because of the elk rutting season (peak mid-September to mid-October). In fall the air is clear and crisp and the skies are blue.
Please make sure to read our full Season Guide below (including monthly weather), tips for Avoiding Tourist Crowds, Hotel Suggestions as well as more useful tips at the end of this article (scroll down!)
Top Tip (Very Easy Hikes)
Tip: Venture off Trail Ridge Road to experience the real beauty of RMNP. If you can't do any strenuous hikes but still want to be awed, then take a look this guide on Amazon: Best Easy Hikes Rocky Mountain National Park. It covers amazing hikes for everyone, even suitable if you visit with small children (like 0.5 miles or 2 miles round-trips). But also hikes which are slightly more challenging. Like John Muir said 'Of all the paths you take in life, make sure a few of them are dirt.'
Highlight (Trail Ridge Road & Tours)
The stunning Trail Ridge Road is open from Memorial Day (last Monday in May) until mid-October. The official closing date is October 23, but they often close it a few days before that date. Even in June or September, it’s possible that it’s closed for hours or a day due to snow, often between 8 PM and 10 AM. Make sure to check more tips for the Trail Ridge Road in our section below the season guide (scroll down).
Special Tour Tip (from Denver or Boulder): If you're staying in Denver or Boulder and would like to experience the Trail Ridge Road as well as the most stunning viewpoints hassle-free, we suggest the Unique Rocky Mountain National Park Tour (from Denver and Boulder). It's an 8 hour day tour which includes driving the amazing Trail Ridge Road as well as other mesmerizing parts of RMNP. The views you'll get to see on this trip are just spectacular. Everything is taken care of, including pick-up service from Denver and Boulder (In case you need a hotel in Denver, check these deals: Denver Hotels)
Regardless of the season: The higher into the mountains you go, the colder it gets. In general, RMNP is known for its extreme weather patterns which can change very quickly, as well as wide variations between day and nighttime temperatures. Find detailed weather data here: Climate Estes Park - Colorado
Spring | April - May
Early Spring in Rocky Mountain National Park
The weather in spring is unpredictable: Up to 70°F (21°C) on one day and a temperature drop together with blizzards on the next day. It varies between warm and cold, wet and dry. Many trails are still snow-covered well into May, often even at the end of May. After a warm April, trails can be snow free in May, but are very muddy. This means you either have to deal with snow or with muddy trails. In general, snowfall is not uncommon in spring. Temperature ranges between 70°F (21°C) and 60°F (16°C).
Summer | June - July - August
Cub Lake in RMNP at Dawn
The most comfortable weather is in the summer months from July to August: The temperature climbs up to 75°F (24°C). However, afternoon thunderstorms can occur and wind is normal. Always prepare for temperature drops of 10-20 degrees Fahrenheit. Keep in mind that the highest elevation trails are snow covered well into June. Wildflowers are in bloom from late June to early August. What to wear in the summer? Always bring layers of clothes, even if you don't plan to hike at higher elevations. A morning can be mild and in the afternoon temps can drop remarkably. Always bring a rain jacket, as well as a warmer long sleeve shirt in your pack. Usually you can start with a short sleeve shirt for hikes or walks.
Fall | September - October - Early November
Autumn is usually a great time for a visit. September and October bring clear, crisp air, blue skies, and generally dry weather. Especially in September it's generally still mild and warm. However, mornings and evenings can be a lot chillier. Always bring a jacket! Early snow is already possible in October. Looking for fall foliage? Leaves start changing colors in late August at higher elevations, peak is around mid-September and the beautiful fall foliage lasts until October in most years at lower elevations. Early October is often still a good time for leaf peeping at lower elevations. At higher elevations the vibrant fall colores will be already gone in October. Elk rutting season begins in September as well and continues through mid-October at least. Like in spring you need to be flexible, check the forecast and bring gear and clothes for various conditions.
Winter | November - March
Winter in RMNP means snow and arctic conditions. However, lower elevations on the east slope of Rocky Mountain National Park are usually free of deep snow. The west side of the park experiences more snow, less wind, and clear cold days during these months. Most high country overnight trips require gear suitable for freezing temperatures. Skiing and snowshoeing conditions are best in January, February, and March. There are lots of other exciting activities in Winter: Sledding at Hidden Valley, Winter Wildlife Viewing, Ice Climbing and more. Visit NPS Rocky Mountain Winter Activities and 20 Things To Do in the Winter. Trail Ridge Road: While it's closed in the winter, keep in mind that you're allowed to drive the first 8 miles until Many Parks Curve overlook. Depending on weather conditions of course.
Avoiding Tourist Crowds
With over 4 million visitors each year, Rocky Mountain National Park is one of the most visited Parks in the U.S. Expect the most crowds in summer and fall. The busiest months are June until August, with heavy crowds in July/August. During the week it starts to thin out after Labor Day in September (first Monday in September), but not on weekends. Also, try to avoid National Public Lands Day at the end of September. Entrance to to all National Parks is free then and RMNP will be extremely busy on this day/weekend!! Visiting mid-week in September means less crowds as well as enjoying elk rutting and pleasant fall temperatures at the same time.
In general from July through September: Avoid weekends and/or go early in the morning to beat the crowds. In the peak months arrive between 7 and 8 AM to get a parking spot. Usually, it starts to get busier after 9 AM. Especially popular entrances like Estes Park or trailheads like Bear Lake Trail are extremely busy. In general, the west side (Grand Lake) is less crowded than the Eastern side (Estes Park Entrance). Regardless of the month, season or entrance: Go as early as possible, head out on a trail, hike a few of miles from the busy areas and you won’t see too many others.
We were there on October 12th, which was a very good balance for us: Late enough to avoid the summer crowds and to see some snow, yet early enough to see some of the aspens with their yellow leave
This is a popular trail, which is beautiful any time of year, although busiest in the summer. The aspens turn in late September/early October.
Time of Day Tip: During peak summer months, the parking lot of this popular trail is already full between 8:30 and 9 AM. If possible, be there early around 7 AM.