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Hindustan Times
6 days ago
- Climate
- Hindustan Times
Weather Bee: How did Rajasthan flood last week?
The heavy spell of rain last week that travelled from West Bengal and Jharkhand to the areas bordering Uttar Pradesh and Madhya Pradesh, and finally to Rajasthan, does not appear usual even for the monsoon season. The spell triggered a flood-like situation in parts of Rajasthan, India's most arid state, resulting in at least 10 deaths across the state between Saturday and Sunday. While a state like Rajasthan can possibly get flooded with even less intense rainfall, an HT analysis shows that last week's spell in Rajasthan, and the other places, was indeed intense. What caused this? The immediate reason was a system of twin storms that lingered over parts of central and north-western India. However, there is also a long-term reason why Rajasthan should prepare for such heavy, flood-inducing rains in the future. The intensity of last week's spell over central and north-western India is evident in the data. The precipitation recorded in the week ending July 20 was more than thrice in many of the affected parts when compared to the average for the same week in the 1971-2020 period. The India Meteorological Department (IMD) calls the 1971-2020 average the Long Period Average (LPA) – the benchmark that serves to gauge rainfall. The regions where this excess was recorded was a narrow band running along the borders of Bihar-Jharkhand, Uttar Pradesh-Madhya Pradesh, and large parts of Rajasthan. Rain departure this year. Unusual rains make most places vulnerable to floods because drainage infrastructure and built-up areas are generally designed according to historical trends in rainfall or the climate of the place. However, even a small amount of rain can appear unusual in Rajasthan, so HT also analysed rain in absolute terms. This showed that last week's rainfall in the region, as mentioned above, was intense even by standards agnostic to the climate of the place. For example, IMD classifies rain in the 7.5-35.5 mm range at a place in 24 hours as 'moderate'. Average daily rain in the week ending July 20 met this threshold for the entire region described above. For parts of the region, the average for the week was more than 35.5 mm, which IMD classifies under different categories of 'heavy' rain. Rain in the week ending July 20. HT looked at rain averaged over the course of a week, because it helps in flagging two scenarios that essentially lead to flooding: One, moderately intense rain spread over a week, which does not allow water to dry and percolate into the ground; and two, very intense spells spread over a day or two that can overwhelm natural and man-made drainage systems not designed to handle such volumes. Why was rainfall intense even when looking at rain averaged over a week? The immediate reason for this is the development of two storms, one after another, that travelled the affected region. This can be seen in the accompanying maps of 850 hPa winds, which are winds at a height of 1.5km above earth's surface – the meteorological conditions here are strong predictors of how storms move. On July 14, the first day of the week analysed here, there was one storm at the Rajasthan-Madhya Pradesh-Uttar Pradesh border (seen in the cyclone-like anti-clockwise movement of relatively faster winds there) and another at the West Bengal coast. By July 17, when the former had travelled across the Punjab border to Pakistan, the latter was making its way almost in the former's footsteps. This second storm — it had wind speed fast enough to be classified as 'depression', two categories below a cyclone — also travelled all the way to Pakistan, but through Rajasthan. This explains why rain was unusually intense in central and north-western India last week. July 14 wind chart July 17 wind chart July 20 wind chart To be sure, while these storms can possibly be an isolated event, monsoon rain has been intensifying over Rajasthan, Gujarat, and parts of Madhya Pradesh over a longer term. HT pointed this out in September 2024 using a paper published in Geophysical Research Letters by Ligin from the University of Southampton and other researchers. As the paper explains, monsoon rain in Rajasthan, Gujarat, and parts of western Madhya Pradesh, is intensifying because winds from the Arabian Sea into the region have become stronger and those away from the region, weaker. This allows moisture to accumulate in the region, a trend that is expected to continue in the future. This is why these regions must prepare for a rainier monsoon than they are used to.
Hindustan Times
12-07-2025
- Climate
- Hindustan Times
Monsoon appears normal so far largely because of June rain
India's southwest monsoon season runs officially from June to September for 122 days. With one-third of the season over, rain's performance in the 2025 season appears to be normal at the national level. However, this has largely been accomplished by June rain and a large surplus in a small region, an HT analysis shows, with July so far the 21st driest July month in 125 years. A biker rides through a waterlogged road after rainfall, in Bengaluru, on Friday. (PTI) According to the gridded data of the India Meteorological Department (IMD), the normal rainfall for the June 1-July 10 period at the country level is 249.6 mm, which is the average rain for the 1971-2020 period and called the Long Period Average (LPA). June 1-July 10 rain in 2025 is 247.2 mm, just 1% less than the LPA. This suggests that the 2025 monsoon is progressing almost exactly as past statistics suggest. As expected from this, the rank of 2025 rain for this part of the monsoon is also roughly in the middle of the distribution: 68th highest in 125 years. However, rain appearing normal in summary statistics does not mean that monsoon has been experienced as normal. For example, June rain was 35th highest since 1901 (the first year for which this data is available), and 9.3% more than the LPA. On the other hand, July rain so far has a 21.5% deficit, and the month is ranked 21st driest since 1901. Clearly, the season has not been normal throughout. In fact, daily trends in rain show that even the first half of June was very dry compared to the LPA. Chart 1 There is more to abnormal rain in the 2025 monsoon season than long dry patches. Even the geographical distribution of rain is skewed. 38% of the country's area has a deficit of 20% or more, which IMD classifies as 'deficient' or 'large deficient' for local rain; and 34% has a surplus of 20% or more, which IMD classifies as 'excess' or 'large excess'. Only around a quarter of the country (28%) has received rain within 20% of the LPA, which IMD classifies as 'normal'. To be sure, even some regions of normal and surplus rain owe that status to June rain. July rain is deficient or large deficient in 58% of the country. As the accompanying maps show, such areas of deficit include regions that average normal or surplus rain for the season as a whole. Most notable among such regions are large parts of Gujarat, southwest Rajasthan, western Madhya Pradesh, northern Maharashtra, Jharkhand, and Odisha. These regions are dry in July, but average normal or surplus rain for the season overall. Map 1 Map 2 Map 3 Clearly, the broad picture of the monsoon season does not tell us that this is just as unusual a monsoon season as any India has experienced in recent years. However, while one-third of the season is past, its rainiest half (the months of July and August) has just started. There is still time for a better geographical distribution of rain.
India Today
11-07-2025
- Climate
- India Today
Monsoon jitters
The southwest monsoons rolled in early this year, covering the whole of India by June 29, nine days before target date. Good rains are crucial for the kharif season, but this year, it looks like we might have it in torrents. Aggregated reports suggest that over 52 districts in 19 states are severely affected by flooding, and it's still only early July. The Indian Meteorological Department predicts 108 per cent of the Long Period Average (LPA) for June-September—and the problem is its erratic trajectory. Rains came early all over the Northeast, wreaking destruction, and it soon began finding unusual company in the Northwest, Central, East and North. Flash floods in Himachal Pradesh and Uttarakhand, the Narmada and Tapi overflowing in Gujarat, reservoirs breaking banks in West Bengal and, now, a second wave in the Northeast, causing flash floods in Manipur, landslides in Mizoram, floods in Arunachal and Meghalaya, with the Brahmaputra and another 10 rivers in spate in Assam. A deluge leaving a whole flood of misery in its wake. - Ends advertisement
India Gazette
10-07-2025
- Climate
- India Gazette
Major rice-producing states, including Bihar, Andhra Pradesh and Assam, receive below-normal rainfall so far: Report
New Delhi [India], July 10 (ANI): Major rice-producing states in India have received below-normal rainfall so far this monsoon season, according to a report by CareEdge Ratings. The report highlighted that states such as Bihar, Andhra Pradesh, and Assam, which together contributed around 15 per cent of the total Kharif rice production last year, have experienced lower-than-normal rainfall since the beginning of the season. 'Among major rice-producing states, below-normal rainfall was observed in Bihar, Andhra Pradesh, and Assam,' the report stated. Despite the shortfall in these key rice-growing regions, the report highlighted that the monsoon has shown signs of improvement overall. Among the 36 meteorological subdivisions in the country, 15 subdivisions, accounting for 43 per cent of the total area, have received normal rainfall since June. Meanwhile, 7 subdivisions, which represent about 13 per cent of the total area, recorded deficient rainfall. The remaining subdivisions saw either large excess or excess rainfall. While the evenness in the spatial distribution of monsoon rains has reduced, it continues to be a key factor to watch in the coming weeks, the report added. Interestingly, the South-West monsoon began earlier than usual this year but weakened midway through June. However, it picked up pace towards the end of the month, which helped push the country's overall rainfall into the surplus category. As of July 7, 2025, India's cumulative rainfall stands at 15 per cent above the Long Period Average (LPA). Region-wise, North-West and Central India saw a strong monsoon performance, with rainfall levels at 37 per cent and 42 per cent above the LPA, respectively. These favourable conditions have supported sowing activities in states like Madhya Pradesh, Rajasthan, Uttar Pradesh, Gujarat, Punjab, and Haryana. In contrast, the South Peninsula recorded rainfall at 1 per cent below normal, while the East and North-East regions saw a significant shortfall of 20 per cent. Despite the uneven rainfall across regions, the report mentioned that the overall increase in sowing activities indicates favourable conditions for agriculture. The report noted that this bodes well for a strong agricultural output for the second consecutive year. (ANI)
India Gazette
02-07-2025
- Business
- India Gazette
Robust 11.3% surge in Kharif sowing bodes well for inflation outlook in 2025: ICICI Bank
New Delhi [India], July 2 (ANI): Kharif sowing in India is off to a strong start this year, recording an 11.3 per cent year-on-year (YoY) increase and it bodes well for the food inflation outlook for the year, according to a recent report by ICICI Bank. The growth has been largely driven by a significant rise in rice sowing, which is up 47.3 per cent YoY, and pulses, which have seen a 37.2 per cent YoY jump. It stated 'Kharif sowing is off to a good start (+11.3 per cent YoY) led by rice (47.3 per cent YoY) and pulses (37.2 per cent YoY) which bodes well for food inflation outlook this year'. The report noted that monsoon rainfall gained momentum in the second half of June after being in deficit during the first half. For the full month of June, rainfall stood at 109 per cent of the Long Period Average (LPA), slightly above the Indian Meteorological Department's (IMD) forecast of 108 per cent. In comparison, June rainfall last year was at 108 per cent of LPA. A regional analysis of rainfall showed that several key agricultural states received rainfall above the LPA. These include Rajasthan, Gujarat, Madhya Pradesh, Haryana, Punjab, Tamil Nadu, Uttar Pradesh, Karnataka, and West Bengal. However, some states such as Bihar, Andhra Pradesh, Telangana, and Chhattisgarh have experienced deficient rainfall. On a zonal basis, Northwest India received the most rainfall at 42 per cent above LPA, followed by Central India at 25 per cent above LPA. Meanwhile, South India recorded rainfall that was 3% below LPA, and East and Northeast India were 17 per cent below LPA. As of June 30, only 10 out of 36 meteorological subdivisions across the country recorded deficient rainfall. This is a marked improvement from last year when 16 subdivisions had reported deficient rainfall by the same time, indicating a better distribution of monsoon this year. Looking ahead, the report also highlighted that rainfall in July is expected to remain favourable. The IMD has forecast rainfall at 106 per cent of LPA for the month, the report added that it should further support kharif sowing activities and improve the overall agricultural outlook. (ANI)
