Seasonal Variations in Himachal Pradesh :

Himachal Pradesh experiences three well defined seasons viz Summer, Monsoon and Winter. Spring is the transition period between Winter and Summer and that between monsoon and winter is autumns.

 Summer :

Summer season begins in Himachal Pradesh from the middle of April and continues till the end of June. The Shivalik hills, Beas valley and Kiarda valley is quite hot in summer with average temperature ranges from 28°C to 32°C. In some parts like Bilaspur, Hamirpur, Una, Paonta, Kalka, Chintpurni, Dehra and Nadaun it has also been recorded above 40°C occasionally. In the areas adjoining to Punjab and Haryana plains, dust rises up and cover the sky at times reducing visibility to barely a few meters. At the beginning and end of summer season there may occur conventional and orographic stormy disturbances.

 Monsoon :

In Himachal, the monsoon displays its myriad wondrous moods. Clouds floating in cobalt skies suddenly turn dark and roll and rumble and bring down showers of rain.The monsoons permeate the consciousness of the Paharis, inspiring them to create beautiful art works. South-West monsoon remains active in the lower and mid-hills from June to September. These rains are heavy on the South-facing slopes of the hills. In many areas, rain may continue for several days at a stretch without break. Many areas also remain cut off from rest of the world for days together due to land slides and blockades. Mountain sides are covered with mist for long periods. The inner dry valleys of the main Himalayas and trans-Himalayan ranges do not receive much rain during the monsoon season, as they fall in the rain shadow belt of the main Himalaya. The rain shadow areas of Himachal Pradesh are:-

• The Lahaul valley across the Pir Panjal up to Udaipur.
• The tract along the Chenab river.
•  The Spiti valley, and
• The upper Satluj valley upstream at Wangtu.

Autumn:

The weather clears in Himachal Pradesh by the end of September and early October. This is the best season in Himachal Pradesh, lasting for two months October and November. There is clear sky and pleasant sun shines. This is also period of fairs and festivals. People from all over the world visit Himachal Pradesh during this period.

Winter:

The winter season follow autumn and continues from November end to March. During winter most parts ofthe state remain snow covered. The higher tracts of Lahaul-Spiti, Pangi Valley, Shimla hills, Chamba and Dhauladhar Pir Panjal ranges experience heavy snowfall. The areas above 2200 meters receive heavy to moderate snowfall. Themercury remain below freezing point. Kangra valley, Beas valley, Shivalik hills and Kiarda valley has pleasant winter with moderate variation between day and night temperature. In Chandrabhaga and Kinnaur valley the climate is semi- arctic in winter-Snowfall normally starts from the end of October and continues till March-April. The remoter parts of the state remain cut off from rest of the world during winter for weeks together and life becomes quite isolated there. Avalanches and snow storms are common in tracts lying above the snow line. Owing to the very low temperature, the inhabitants of higher Himalayas migrate to the lower hills along with their livestock and start returning in March and
April. The Northern cold dry winds and Western disturbances affect the state in winter.

Spring :

The spring season commences in the state from March and concludes by the end of April. In Spring and autumn maximum trade activities are performed by the people of the state. This is the transition period from winter to summer. The lower tracts may experience rainfall sand upper parts have snowfall during spring. The state can aptly be divided into four climatic regions on the basis of climatic conditions like temperature and precipitation, latitude and altitude.
Arctic : over 4500 meters
Sub-arctic : 3500-4500 meters
Temperate : 2000-3500 meters
Tropical below : 2000 meters

The climate of Himachal Pradesh varies at different altitudes. The average rainfall is 152 cms (60 inches). The highest rainfall is in Kangra district at Dharamsala and lowest in Lahaul-Spiti at place Spiti.