Seasons of India
The Indian Meteorological Department (IMD) recognises four seasons. The monsoon season has two phases: advance and retreat.
| Season | Months | Main features |
|---|---|---|
| Cold weather (winter) | Mid-December to February | Clear skies, cool dry weather, north-east winds, western disturbances give rain in the north-west |
| Hot weather (summer) | March to May | Rising temperature, loo (hot dry wind), dust storms, pre-monsoon showers in the south and east |
| Advancing south-west monsoon (rainy) | June to September | Moist south-west winds, onset on the Kerala coast about 1 June, withdraws from the north-west by mid-September |
| Retreating monsoon (post-monsoon) | October to November | Falling temperature, October heat, cyclones on the east coast, north-east monsoon over Tamil Nadu |
Cold weather season
- January is the coldest month in the north; the mean temperature in the north is 10-15°C and in the south about 24-25°C.
- High pressure over north-west India; winds blow from land to sea (north-east trade winds), so most of the country is dry.
- Western disturbances bring rain to Punjab, Haryana, Delhi, Himachal and J&K, and snow in the hills. The rain is called mahawat in north India and is important for wheat.
- Tamil Nadu coast gets rain in winter from the north-east monsoon.
Hot weather season
- Sun moves north; April-May is the hottest in the peninsula and May-June in the north.
- Loo: hot, dry, strong wind in the afternoon in the north-western plains.
- Local storms of this season:
| Local name | Region | Notes |
|---|---|---|
| Mango showers | Kerala and Karnataka | Help ripen mangoes |
| Blossom showers | Kerala, coffee areas of Karnataka | Help coffee flowering |
| Nor'westers (Kalbaisakhi) | West Bengal, Assam, Odisha, Bihar | Violent thunderstorms, good for tea, jute, rice; called Bardoli Chheerha in Assam |
| Andhi | Punjab, Haryana, Rajasthan | Dust storms |
South-west monsoon season
- Onset around 1 June at Kerala; covers the whole country by about 8 July (normal date; recent years have been earlier). Withdrawal begins from west Rajasthan about 17 September and ends by mid-October.
- Two branches: the Arabian Sea branch and the Bay of Bengal branch. See Monsoon Mechanism.
- Break in monsoon: dry spell in the rainy season when the monsoon trough shifts toward the Himalayas.
Retreating monsoon
- The sun moves south; the monsoon trough weakens; the sky clears. Air is humid with high day temperature, called October heat.
- Tropical cyclones form in the Bay of Bengal and strike the Odisha, Andhra and Tamil Nadu coasts.
- The north-east monsoon brings rain to the Coromandel coast in October-December.
Keep practising
Notes are only half the work. Test yourself with questions and discuss doubts with other aspirants.
Prepared for exam revision from NCERT, standard geography textbooks, the Census of India 2011, the India State of Forest Report, IMD, Ministry of Agriculture and other official sources. Maps are schematic teaching maps, not Survey of India maps, and zone boundaries are approximate. Figures such as production, capacity, counts of parks and ports, and census status change, so check the latest official source before relying on them. Found a mistake? Tell us.