Summers, specifically from April to June, are considered the best months to embark on the Har Ki Dun trek. During this time, the weather is incredibly pleasant, characterized by warm days and cool nights, making it ideal for trekking. The snow in the lower altitudes begins to melt, giving way to a vibrant display of blooming flowers, while the higher peaks remain adorned with pristine snow, creating a picturesque contrast that is truly breathtaking.

Although afternoon showers are common during the summer months, the weather generally remains clear and stable, ensuring a comfortable and enjoyable trekking experience. However, towards the end of June, the onset of the monsoon season brings an increased likelihood of rainfall, leading to slippery trails and potential safety hazards. Consequently, the Har Ki Dun Wildlife Sanctuary is closed for visitors' safety.

Despite the closure of the sanctuary, August can still be a unique time to consider the trek for adventure enthusiasts. However, it's crucial to be aware of the associated risks, including unpredictable weather conditions and challenging terrain, which can add an element of thrill to the journey.