Climate of Himachal Pradesh :

 Climate of any place is dependent on various geographical factors. The state of Himachal Pradesh, India is a hilly region and it experiences a pleasant Climate through out the year. It even experiences heavy snow fall during the winter months. The weather of Himachal alters with the change of altitude. The best time to visit the state of Himachal is from September to March.

There is a huge variation in the climatic conditions of Himachal Pradesh due to variation in altitude (450–6500 metres). The climate varies from hot and sub-humid tropical (450–900 metres) in the southern low tracts, warm and temperate (900–1800 metres), cool and temperate (1900–2400 metres) and cold glacial and alpine (2400–4800 metres) in the northern and eastern high elevated mountain ranges.

By October, nights and mornings are very cold. Snowfall at elevations of nearly 3000 m is about 3 m and lasts from December start to March end. About 4500 m, is perpetual snow. 

The spring season starts from mid February to mid April. The weather is pleasant and comfortable in the season.

The rainy season start at the end of the month of June. The landscape lushes green and fresh. During the season streams and natural springs are replenished. The heavy rains in July and August cause a lot of damage resulting in erosion, floods and landslides. Out of all the state districts, Dharamsala receives the highest rainfall, nearly about 3400 mm. Spitiis the driest area of the state (rainfall below 50mm). The reason is that it is enclosed by high mountains on all sides.

The temperature of Himachal Pradesh is highly dependent on altitude. The average altitude of the region is from 350 meter to 700 meter above sea level. The region generally experiences three seasons. The winter season spans from October to February. The summer months in Himachal are the months of March to June. By July the rainy season starts in the hilly region and it ends in September. In the winter months, some parts of Himachal experiences heavy snow fall. It occurs generally in the months of December to March. The days and nights during this time of the year become very cold.

The Weather and Climate of Himachal Pradesh becomes very beautiful after the rainy season. The landscape of the place become lush green. But heavy rains often cause floods and landslides causing destruction to life and property. The highest amount of rainfall that has been recorded in Dharmasala is 3400 mm. The annual rainfall of Himachal Pradesh is 2909 to 3800 mm. The average temperature in the summer months vary from 22 degrees to 37 degree Celsius. The temperature varies from 0 degree to 15 degree Celsius.

Recent trends observed in Parvati basin :

• Significant decreasing average annual and seasonal discharge in the Parvati watershed of northwest Himalayan region have been observed.
•  Winter discharge decline was observed to be the sharpest.
• Both parametric and non-parametric tests showed that decreasing trend was significant at 95% of confidence level.
•  Reduction in glaciated areas have been observed during 1963 through 2006 but this reduction in glaciated mass have not contributed towards the increase in discharge of the Parvati watershed.
•  Flow characteristics in the Parvati watershed appears to be controlled to a large extent by the variation of rainfall and not by the glaciated areas Contd. Analysis of temperature data from the Parvati watershed revealed  notably upward trends in winter temperature
• The increase in winter temperature may result in a changed proportion of precipitation falling as rain near the freezing level and this may have little effect at higher elevations where greatest accumulation occurs.
•  Runoff from foothill and snow-fed catchments may be significantly affected but there may be limited impact on runoff on glacier-fed catchments.