You can visit round the year in Uttarakhand. There are no restrictions of any kind. While as Char Dham like Badrinath – Kedarnath – Gangotri and Yamunotri shrines remain close from November to Mid May. Though rest of the destinations remain open round the year
Monsoon season considered in Uttarakhand - India from end of June to Mid September. It will be very much enjoyable to travel in deep shivalik ranges of Himalaya. Lush green mountains, clean weather and mist traveling from your window will take you to divine feelings. Though you must take precautions with heavy rain fall which may cause landslides. Valley of flowers is most suitable destination to visit at this time of the year when most of the flowers blooms in the valley. Some of them are very rare such as Brahmkamal and Blue poppy. July and August is the best time to travel in Valley of Flowers.
Summers in Uttarakhand considered from Mid April Till end of June when temperature may be minimum 15 D Celsius to 35D Celsius. May and June is the peak season to explore all hill stations in Uttarakhand. Char Dham yatra starts Mid may onwards therefore you can plan your trip accordingly. You can plan your trekking trips in summer wither for Gaumukh glacier – Panwali Kantha Trek – Kuwari Pass Trek or Bedini Bugyal Trek – Pindari Glacier – Sundar dhungla Glacier etc..
Winter season in Uttarakhand considered from October to March. If you wisht o enjoy with the snow you may plan your trip in the month of January and February. Musoorrrie – Nainital – Auli – Munshrai may be your most favourate destinations. If you are planning for skiing – Auli will be best to enjoy with snow and breathtaking panorama of Nanda Devi group of peaks and Trans Himalayan Ranges.