Monsoon: Quick Facts

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Last updated

Oct. 25, 2026

News •

Monsoon gains strength in Tamil Nadu; heavy rainfall to continue till October 26 • Oct. 22, 2026, 11:51 AM ET (The Hindu)

Photos

Two world maps compare the Indian monsoon's climatic heat sources and sinks. The top map, labeled Summer Monsoon, highlights the monsoon trough over South Asia as a major heat source and the Mascarene High over the southwest Indian Ocean as a heat sink, with arrows indicating surface air flow from the ocean toward the continent. The bottom map, labeled Winter Monsoon, shows the Siberian High over northern Asia as a heat sink and the Maritime Continent region as a heat source, with air flow arrow

Two side-by-side maps of Australia show seasonal rainfall patterns and the path of the Australian monsoon. The left map, for October 1 to April 30, displays bands of increasing rainfall from the interior to the northern and northeastern coasts, with black arrows indicating monsoon winds moving from the northwest across northern Australia. The right map, for April 1 to November 30, shows generally lower rainfall amounts, with the highest rainfall still in the north but no arrows indicating wind d

Workers holding umbrellas harvest tea leaves among lush green bushes in an Assam tea plantation during monsoon rains, with tall trees in the background.

Map showing the average date of onset of the summer monsoon across Asia.

Map showing the withdrawal of the Indian monsoon, with orange lines and dates indicating the typical retreat timeline from northwestern India and Pakistan in early September, gradually moving southeast across the Indian subcontinent and reaching Sri Lanka by January 1. Surrounding countries and major water bodies such as the Arabian Sea and Bay of Bengal are labeled.

Map of Pakistan showing areas affected by the 2010 flooding, with regions along the Indus River marked in red for severely affected areas and orange for moderately affected areas. Major cities such as Karachi, Sukkur, Hyderabad, Multan, Lahore, Peshawar, and Islamabad are labeled, along with provincial and international boundaries. Neighboring countries including Afghanistan, India, and China are also indicated.

Two side-by-side maps of Africa show the seasonal path of the African monsoon. Arrows indicate wind systems, including the northeast trade winds and the hot, dry Harmattan winds. Shaded bands in varying greens represent rainfall amounts, with the Intertropical Convergence Zone shifting northward and rainfall bands reaching farther into West Africa from June to September, and moving southward with rainfall concentrated in central and southern Africa from January to March.

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Topics

Indian monsoon West African monsoon Malaysian-Australian monsoon summer monsoon break of the monsoon winter monsoon burst North American monsoon El Niño wet season tropical cyclone tropical storm Intertropical convergence zone Trade wind Why is summer warmer than winter?Autumn Spring Why do we have seasons?Winter Summer

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