Cold weather season
Also called: Winter season · Topic: Climate of India and the Monsoon · NCERT: Class 11, Ch 4 "Climate"
Meaning
The cold weather season begins by mid-November in north India and lasts until February (Class 11: December-February). December and January are the coldest months. Mean temperatures stay below 21°C, and there is frost in Punjab and Rajasthan. There are three reasons for the cold:
- continentality, which means being far from the sea's moderating effect
- snow on the nearby Himalaya
- cold winds from the Caspian Sea and Turkmenistan in February
A weak high-pressure area lies over the northwest, and light winds blow from land to sea at 3-5 km/h. Western disturbances are shallow lows from the east Mediterranean. They bring light rain that helps rabi wheat. The south has no well-defined cold season.
Example
Delhi gets about 53 mm of winter rain from western disturbances, which is good for wheat in Punjab and Haryana. Thiruvananthapuram in Kerala, by contrast, stays warm in January.
Don't confuse with
- Northeast monsoon: the same winter winds pick up moisture over the Bay of Bengal and soak the Tamil Nadu coast in October-December. The north stays mostly dry.