Indian subcontinent weather varies from region to region, it is mainly hot most of the year. The chilling season starts around the end of November and ends to the beginning of March. The real hot weather, is between March and July. Monsoon rains occur in most regions in summer anywhere between July and early October.
Below is the Indian subcontinent weather details as per the zones:
Western Himalayas: Srinagar is best from March to October; July to August can be cold and damp in winter. Shimla is higher and therefore colder in winter. Places like Gulmarg, Manali and Pahalgam are usually under several feet of snow from December to March and temperatures in Ladakh, which is a high-altitude desert, can be extremely cold. The mountain passes of Ladakh are accessible from July to October due to heavy snow fall.
Northern Plains: Cities like New Delhi, Varanasi, Lucknow and Patna experience an extreme range of temperatures and are typically warm from April to mid-June, falling to almost freezing at night in winter between November and February. Summers are hot with monsoons between June and September.
Central India: Madhya Pradesh state escapes the very worst of the hot season, but monsoons are heavy between July and September. Temperatures fall at night in winter.
Western India: November to February is most comfortable, although evenings can be fairly cold. Summers can be extremely hot with monsoon rainfall between mid-June and mid-September.
Eastern India: Weather in states like Orissa (which is flood-prone) are defined by cooler weather from October to February, scorching heat from March to May and unavoidable drenching from the monsoons from June to October.
Southwest: The most pleasant weather is from November to March. Monsoon rains fall anywhere between late April and July. Summer temperatures are not as high as Northern India although humidity is extreme. The coast benefits from some cooling breezes. Inland, Mysore and Bijapur have pleasant climates with relatively low rainfall.
Southeast: Tamil Nadu experiences a northeast monsoon between October and December and temperatures and humidity are high all year. The hills can be cold in winter.
Northeast: March to June and September to November are the driest and most pleasant periods. The rest of the year has extremely heavy monsoon rainfall.