Climate
| Climate | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
| Daily highs °F | 38 | 40 | 44 | 53 | 62 | 72 | 78 | 76 | 70 | 60 | 46 | 39 |
| Nightly lows °F | 16 | 17 | 20 | 27 | 34 | 41 | 46 | 44 | 37 | 30 | 22 | 17 |
| Precipitation in | <1 | <1 | <1 | 1 | 2 | 2 | 2 | 2 | 1 | <1 | <1 | <1 |
| The above measurements are for Estes Park. Temperatures in the mountains can be 10-15°F 5-7°C cooler. |
Considering the park's high altitude, the weather trends closer toward moderate four-season climate than edging on the extremes. Winters bring heavy snowfall, and although there is rarely a deep-freeze the park gets significantly less visitors. Summer are the high season with warm temperatures ranging in from mid 70s-80°F during the day, but dropping into the low 40s°F to near freezing. Thunderstorms are constantly looming in the early to mid afternoon during the summer, but clear off quickly by evening, bringing crisp and cool weather.
Flora and fauna
For wildlife seekers, Rocky Mountain National Park offers some fantastic opportunities to view the variety of animals that live inside its borders. Elk, deer, chipmunks, ground squirrels, beavers, porcupines, foxes, and coyotes are all commonly seen in meadows and in and around lakes and streams. Marmots seem to be ubiquitous above the tree line, especially on well-hiked trails around Longs Peak. Hawks and eagles are often seen soaring above the glacier gorges in search of critters that hide among the rocks and colorful tree birds such as blue jays and cardinals fly in the lower altitudes. Hummingbirds have a tendency to fly close to where people - and their food - are sitting. Less common animal sightings include black bears and the rare mountain lions, although the former will manage to hang out if human food is accessible. Moose mainly stay on the western side of the park and Bighorn Sheep - a rare but exciting find - stay above the tree line and can sometimes be seen off the Trail Ridge Road.
Wildflowers seem to be everywhere throughout the park, including the popular Indian Paintbrush and Columbine, Colorado's state flower. One of the most spectacular sights in the mid to late fall is to walk through a grove of Aspen trees as their leaves change from green to gold. Ponderosa and Lodgepole pines are the dominate conifer trees in the area, although they have been recently dying in large numbers due to an outbreak of pine beetle infestation.
Orientation
Highway 34 connects Grand Lake and Estes Park across the Continental Divide, giving you awesome views of the western and eastern sides of the park. A great stopping point along the road is the Alpine Visitor Center at the Fall River Pass, which sits at almost 11,800 feet. Colorado Route 7 runs from Estes Park to the south, passing by several trailheads, including those for Lily Mountain, the Twin Sisters, the Longs Peak Ranger Station and the Wild Basin. Many visitors use Bear Lake or Glacier Gorge as their starting point into the park, both of which can be accessed via the Bear Lake Road. The Beaver Meadows and Moraine Park visitor centers are popular destinations for getting oriented with the park's layout, the former having been designed by students of American architect Frank Lloyd Wright.
History
Evidence of Native American peoples visiting the park date back almost 10,000 years, mainly from the Ute and Arapaho communities. Several expeditions visited the area in the early to mid 19th century, including one by Joel Estes in 1859 after which he and his family established a homestead that would soon become Estes Park, the resort town that currently sits on the east side of the park. After a small mining rush on the western side of the park in the early 1880s, a 14 year old boy by the name of Enos Mills moved to the area and began to extensively document the region's geography and ecology through essays and books. He began to lobby Congress to establish a national park in the area surrounding Longs Peak, a mountain he had climbed over 40 times by himself. On January 26, 1915, President Woodrow Wilson signed a bill that established the creation of Rocky Mountain National Park. The 1930s brought a building boom to the park during the Great Depression, during which time the Trail Ridge Road was constructed through the park, which remains today the highest continuous stretch of highway in the United States.
Landscape
Rocky Mountain National Park sits on the Continental Divide, separating the park into two distinct regions. The eastern and more developed side of the park is dominated by striking valleys and cirques that were formed through heavy glaciation and is a good starting point for first-time visitors. The western side of the park is wetter, is heavily forested and is less developed, but still contains excellent trekking and backcountry opportunities. Most areas of the park sit well above 9,000 feet with mountains along the Continental Divide topping off at above 12,000 feet. The 13,000 foot Mummy Range rests on the northern side of Rocky Mountain National Park with two roads skirting long it's southern edges; a one-way, dirt road that winds up the Fall River called the Old Fall River Road; and a section of Highway 34 famously known as the Trail Ridge Road. The Never Summer Mountains sit on the western side of the park and consist of 10 distinct peaks, all rising well over 12,000 feet, and contain the headwaters for the Colorado River. One of the most dominating features in the southeast area of the park is Longs Peak at 14,259 feet, which is surrounded on all sides by several peaks well about 13,000 feet, including Mt. Meeker, Mount Lady Washington, and Storm Peak.