The climate of Uttarakhand is sharply demarcated in case of its two distinct divisions: the predominant hilly terrain and the smaller plain region. The most favorable time to visit Uttarakhand happens to be in the course of the summers when the weather is very clement and mild. Certain areas of the hills even become inaccessible in winter due to extremities of climate causing prolonged snowfall. The plain region seems to be at its best in terms of climate in winter, when the weather is pleasant.
The type of climate that is mainly to be found in the plains closely resembles the corresponding state in the Gangetic plain. Summers are exceedingly hot with temperatures crossing the 40°C mark and considerable humidity. Winters can be chilly with temperatures going below 5°C at times.
The climate in the northern part of Uttarakhand is typically Himalayan. This mountain range itself exerts an appreciable extent of influence on monsoon and rainfall patterns. Within the Himalayas, climate differs depending on altitude and position.
Climate ranges from subtropical in the southern foothills, averaging summer temperatures of about 30° C (about 86° F) and winter temperatures of about 18° C (about 64° F).
Warm temperate conditions prevail in the Middle Himalayan valleys, with summer temperatures usually hovering about the mark of 25° C (about 77° F) and cooler winters.
Cool temperate conditions dominate the higher areas of the Middle Himalayas, where the summer temperatures are usually around 15 to 18° C (59 to 64° F) and winters drop below the freezing point.
You will encounter a cold alpine climate at higher reaches where summers are cool and winters are harsh.
At altitudes over 4880 meters (16,000 feet), the climate is bitterly cold with temperatures consistently below the freezing point and the area perennially shrouded in snow and ice.
The eastern flanks of the Himalayan ranges are subject to heavy rainfall while the western section is relatively dry.
Uttarakhand is characterized by two types of climate, sharply differentiated in the plains and the mountainous regions.