Weather in the mountains is notoriously difficult to predict. Of course, at night it is generally cold, and in winter the days can be quite beautiful if the sun is out. There can be snow or rain storms any time of the year. Trekking in spring (March – April) is particularly lovely as the rhododendrons are in full bloom, and the mountains still have plenty of high snow to enhance your photos. You need to be aware that it can get pretty hot and sunstroke can be a risk. Good polarizing sunglasses or glacier glasses (not trendy fashion ones) for high altitudes/winter treks, and a large brimmed hat are a necessity. It is also important to make sure that you can stay warm and dry in just about any conditions. Expect the unexpected!  Between 1000m and 3500m the temperature could be as high as 20 deg C to 5 deg C low. At higher altitudes, the temperature ranges from 20 deg C to -10 deg C. During winter it is around 10 deg colder.