Climate & Monsoon

The onset of the monsoon is associated with the sudden shift of the ITCZ and the strengthening of Equatorial Westerlies towards the Indian subcontinent.

Mango showers occur towards the end of summer in Kerala and coastal Karnataka, helping in the early ripening of mangoes.

The North-East Monsoon, or the retreating monsoon, picks up moisture from the Bay of Bengal and causes rainfall on the Tamil Nadu coast.

Western Disturbances are extratropical storms originating in the Mediterranean region that bring moisture to Northern India during winter.

As moisture-laden winds rise over the Western Ghats, they shed most of their moisture; the descending air on the other side warms up, creating a rain shadow.

Loo refers to the strong, dusty, hot, and dry summer winds that blow over the western plains of India and Pakistan.

India is globally classified as having a tropical monsoon type of climate due to the seasonal reversal of winds.

The word 'Monsoon' is derived from the Arabic word 'Mausim', which means season.

Inland locations like Delhi experience a greater range of temperatures because they lack the moderating effect of the sea.

During winter, the land cools faster than the sea, leading to the development of a high-pressure zone over North-Western India.

The intense heating of the Tibetan Plateau acts as a strong heat source, which pulls the monsoon winds towards the Indian subcontinent.

As the monsoon retreats, the skies clear and temperatures rise slightly, but high humidity makes the weather oppressive; this is termed 'October Heat'.

The Coromandel Coast (Tamil Nadu) receives significant rainfall during the North-East monsoon period (October-December).

Kal Baisakhi, or Nor'westers, are localized thunderstorms in West Bengal during the summer season.

Mawsynram in Meghalaya receives the highest average annual rainfall in the world due to the orographic lifting of monsoon winds against the Khasi Hills.

The Tropic of Cancer passes through the middle of India, dividing it into nearly two equal halves—the tropical zone in the south and the subtropical zone in the north.

The Tropical Easterly Jet stream is a key factor that helps in the northward movement of the monsoon over India.

El Nino is the anomalous warming of sea surface temperatures in the Central and Eastern Pacific, which often negatively impacts the Indian Monsoon.

The winter monsoon is generally dry for most of India as winds blow from land to sea; Western India remains mostly dry except for winter disturbances.

The monsoon trough is a low-pressure area that develops over the Gangetic plains during the monsoon season, facilitating the influx of moisture-laden winds.

The withdrawal of the Southwest Monsoon is triggered by the southward movement of the Subtropical Westerly Jet Stream across the Himalayas in September.

The Coromandel Coast receives significant rainfall during winter from the moisture-laden retreating Northeast Monsoon winds blowing across the Bay of Bengal.

Andhi refers to the intense, localized dust storms that frequently occur in the arid and semi-arid northwestern plains of India during the peak of summer.

The Tibetan Plateau acts as a massive heat source in summer, warming the upper air and helping to establish the Tropical Easterly Jet, which intensifies the monsoon.

The Aravalli range runs parallel to the direction of the Arabian Sea branch of the monsoon winds, providing no orographic obstruction to cause rainfall.

La Niña is characterized by cooler-than-normal sea surface temperatures in the equatorial Pacific, which is generally associated with a stronger-than-normal Indian monsoon.

A 'break' in the monsoon occurs when the monsoon trough moves close to the Himalayas, leading to dry conditions over the plains while the foothills experience heavy rainfall.

The Bay of Bengal is highly prone to cyclonic depressions during the retreating monsoon (October-November), which frequently impact the Odisha and Andhra coasts.

Bordoi Chila is the local name for the violent pre-monsoon squalls and thunderstorms in Assam, similar to Kal Baisakhi in Bengal.

In Koeppen's classification, 'Amw' represents a tropical monsoon climate with a short dry season, typically found on the west coast of India.

The Mascarene High is a high-pressure zone in the South Indian Ocean; its intensity determines the strength of the cross-equatorial flow of monsoon winds.

During July, the ITCZ shifts northward over the Indo-Gangetic plain, creating a 'monsoon trough' that attracts the Southwest monsoon winds.

The onset date varies based on the location's latitude, its distance from the moisture source, and the influence of local topographical features.

The Deccan Plateau lies on the leeward side of the Western Ghats, receiving significantly less rainfall because the mountains block moisture-laden winds.

Western Disturbances are extratropical storms originating in the Mediterranean region that bring winter precipitation to Northwest India.

Rajasthan contains the Thar Desert, which constitutes the largest arid zone in India, significantly influencing the region's climate.

Blossom showers occur in Kerala and nearby areas and are crucial for the blooming of coffee flowers.

The cold weather season (winter) in India is marked by clear skies, low temperatures, and low humidity due to the influence of continental winds.

The Southern Oscillation is the see-saw pattern of meteorological changes observed in the South Pacific Ocean, linked to the Indian monsoon via the Walker Circulation.

Leh is located at a very high altitude in the rain-shadow area of the Himalayas, leading to extreme cold temperatures, earning it the title of the 'Cold Pole' of India.

The shifting of the Inter-Tropical Convergence Zone (ITCZ) and the upper-air circulation in the troposphere (like the Tropical Easterly Jet) are vital for monsoon progression.

Kal Baisakhi showers are highly beneficial for the tea gardens of Assam and West Bengal, often referred to as 'Tea Showers'.

The Coriolis force, caused by the Earth's rotation, deflects the trade winds to the right in the northern hemisphere, turning them into the South-West Monsoon.

The massive differential heating of the Indian landmass compared to the surrounding Indian Ocean creates a low-pressure gradient that draws moist winds inward.

Leh is a high-altitude cold desert and lies in the rain-shadow region of the Himalayas, receiving minimal annual precipitation.

The heating of the Tibetan Plateau acts as a high-altitude heat source, helping to establish the Tropical Easterly Jet, which aids in the monsoon's intensity.

The intensity of the Mascarene High (near Madagascar) is directly proportional to the strength of the monsoon winds blowing toward India.

As the monsoon retreats, winds blowing over the Bay of Bengal pick up moisture and strike the Coromandel coast, giving Tamil Nadu its peak rainfall in Oct-Dec.

Temperature inversion, where cold air settles in valleys and warm air stays above, traps pollutants and moisture, leading to the formation of dense winter fog.

Intense surface heating in the northern plains leads to the rising of hot air and subsequent convectional rainfall, often accompanied by storms.