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Withdrawal of the Southwest Monsoon: How Does IMD Determine When the Monsoon Retreats from India?

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The withdrawal of the southwest monsoon has begun over India. On 19 September 2026, the India Meteorological Department (IMD) declared the withdrawal of the southwest monsoon from some parts of West Rajasthan, marking the beginning of the seasonal retreat of the monsoon. The arrival of the southwest monsoon is one of the most closely watched weather events in India. But its departure is equally important. The withdrawal of the monsoon marks a major transition in India's atmospheric circulation, gradually bringing an end to the southwest monsoon season and preparing the atmosphere for the post-monsoon season. But how does the India Meteorological Department determine that the southwest monsoon has started withdrawing? IMD uses a set of meteorological and synoptic criteria to identify the beginning of withdrawal and then monitors its progressive retreat across the country. With the southwest monsoon beginning its withdrawal in 2026, this is a good opportunity to understand how mons...

Status of Southwest Monsoon 2026 (June-August) and Outlook for September

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The Southwest Monsoon 2026 commenced over Kerala on 4 June , slightly later than its normal onset date of 1 June. Thereafter, the monsoon advanced across the country and covered the entire country by 9 July . a) Rainfall during June–August 2026 The country experienced a deficient June, followed by a near-normal July and another deficient August. June: 106.8 mm against a normal of 165.3 mm — 35.4% below normal July: 283.3 mm against a normal of 280.5 mm — 1.0% above normal August: 213.5 mm against a normal of 254.9 mm — 16.3% below normal Consequently, cumulative rainfall during 1 June–31 August 2026 was 603.7 mm, compared with the normal of 700.7 mm, giving an overall deficiency of 13.8%. Thus, despite a substantial recovery during July, the rainfall deficit accumulated during June could not be completely compensated, and rainfall again remained below normal during August. Region   June 2026      July 2026       August 2026   ...

Southwest Monsoon 2026: Mid-Season Assessment (End of July)

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By the end of July, nearly half of India's southwest monsoon season (June–September) has been completed. This provides an opportunity to review the progress of the monsoon and understand what may happen during the remaining months (August–September). 1. Monsoon onset and advance The southwest monsoon onset over Kerala occurred on 4 June 2026, about three days later than the normal onset date of 1 June. Following its onset, the monsoon advanced steadily across the country, with periods of rapid progress interspersed with temporary pauses. It eventually covered the entire country on 9 July 2026, about six days earlier than the normal date of 15 July. It is important to note that the timing of monsoon onset or its rate of advance does not determine the seasonal rainfall over India. The seasonal rainfall depends on the evolution of large-scale climate drivers such as El Niño–Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD), intraseasonal oscillations such as the Madden–...

Understanding Heavy Rainfall Events in India During El Niño Years

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Introduction When people hear that El Niño is expected to weaken the Indian summer monsoon , they often assume that rainfall will remain uniformly low throughout the season. This is one of the most common misconceptions about the monsoon. Seasonal rainfall and daily rainfall extremes are not the same thing. A season can end with below-normal total rainfall , yet still witness episodes of extremely heavy rainfall over localized regions. Unfortunately, these short-lived but intense rainfall events are often the ones responsible for floods, landslides, urban inundation, and significant loss of life and property.       "El Niño influences the seasonal total rainfall over India, not every individual rainfall event. Therefore, even in an El Niño year with below-normal seasonal rainfall, some regions can still experience episodes of extremely heavy rainfall capable of causing severe floods and landslides." The widespread heavy rainfall observed across India during the past few...

Schools Reopened After Heavy Rainfall: Safety Measures for Safe School Travel

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Introduction After remaining closed for two days due to heavy rainfall, many schools in Pune reopened today. The decision reflected the improving weather situation, with the risk of further heavy rainfall having reduced. Yet, across several parts of the city, the impacts of the previous days' rainfall were still evident. Waterlogged roads, inundated low-lying areas, overflowing drains, damaged road surfaces, and traffic disruptions continued to affect daily life. This situation offers an important reminder: the end of heavy rainfall does not necessarily mean the end of risk. The Rain May Stop, But the Risks Can Persist Weather forecasts help us understand the likelihood of future rainfall, but they cannot instantly remove the impacts of rain that has already fallen. Even after the skies clear, the effects of heavy rainfall often remain for hours or even days. Residual hazards may include: Waterlogged roads concealing potholes or open drains. Flooded underpasses and low-lying street...

बदलती जलवायु में स्वास्थ्य सुरक्षा: पूर्वानुमान से उपचार तक

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 लेख के बारे में यह लेख मूल रूप से ‘संगम’ (अंक 1, वर्ष 2026) पत्रिका में प्रकाशित हुआ था। बदलती जलवायु के कारण स्वास्थ्य पर बढ़ते प्रभाव—जैसे लू, बाढ़, सूखा तथा जलवायु-संवेदनशील रोगों के प्रसार—आज एक महत्वपूर्ण वैश्विक और राष्ट्रीय चुनौती बन चुके हैं। इस लेख में मौसम एवं जलवायु सेवाओं की भूमिका पर प्रकाश डाला गया है, जो समय पर चेतावनी, जोखिम आकलन तथा स्वास्थ्य क्षेत्र की तैयारी को सुदृढ़ बनाकर जन-स्वास्थ्य सुरक्षा में महत्वपूर्ण योगदान देती हैं। यह लेख जलवायु परिवर्तन, स्वास्थ्य और जलवायु सेवाओं के परस्पर संबंध को सरल भाषा में समझाने का प्रयास है। चित्र 1. संगम (अंक 1, वर्ष 2026) पत्रिका का आवरण पृष्ठ, जिसमें "बदलती जलवायु में स्वास्थ्य सुरक्षा: पूर्वानुमान से उपचार तक" लेख मूल रूप से प्रकाशित हुआ था। मूल लेख जलवायु परिवर्तन अब केवल बढ़ते तापमान या पिघलते हिमनदों तक सीमित विषय नहीं रह गया है; यह एक गंभीर जन-स्वास्थ्य चुनौती बन चुका है, जो लोगों के दैनिक जीवन को सीधा प्रभावित कर रहा है। बढ़ता तापमान, वर्षा के बदलते स्वरूप, चरम मौसम घटनाओं की बढ़ती आवृत्ति और बिगड़ती वायु गु...

El Niño, La Niña and the Indian Monsoon: A Climate Story from the Pacific Ocean to India

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Introduction Every few years, changes in ocean temperatures thousands of kilometers away in the tropical Pacific Ocean capture global attention. Terms such as El Niño , La Niña , and even Super El Niño begin appearing in weather and climate forecasts and news headlines. These phenomena are part of the El Niño–Southern Oscillation (ENSO), one of the most important drivers of year-to-year climate variability on Earth. But what do these terms mean, and how can changes in the distant Pacific Ocean influence the Indian monsoon? The answers lie in a fascinating scientific story that connects the Pacific Ocean, the Indian monsoon, and the pioneering work of Sir Gilbert Walker, who sought to unlock the secrets of monsoon prediction while serving in India more than a century ago. What are El Niño and La Niña? El Niño and La Niña are opposite phases of the El Niño–Southern Oscillation (ENSO), a naturally occurring ocean-atmosphere phenomenon in the tropical Pacific Ocean. El Niño El Niño occurs...