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The Hindu
5 days ago
- Climate
- The Hindu
Unusually high-speed winds over Kerala, a throwback to 2018
The unusual pattern of high-speed wind in Kerala since the onset of the monsoon bears close resemblance to the wind that lashed the State in 2018, just ahead of the August floods that year. The speed of the monsoon low-level jet measured in the wind profiler radar of the Cusat's Advanced Centre for Atmospheric Radar Research (ACARR) was 20 m/s (approximately 72 kmph) at around 2 km height from the surface on Thursday. In 2018, the core speed of the monsoon low-level jet was about 20 m/s on August 14, the day ahead of the flood. This is unusual considering the climatological normal of the low-level jet speed over Kerala, which used to hover around 10-15 m/s, said Ajil Kottayil, scientist, Advanced Centre for Automatic Radar Research. The higher speed of westerly winds will normally pump a large quantity of moisture from the Arabian Sea to the land. Further, the orographic lifting of clouds, including their depth and extent, would be higher than normal during such situations, leading to intense spells of rain over the land, said Mr. Kottayil. In various districts The automatic weather stations under the India Meteorological Department also recorded high gusty winds across the State. Palakkad recorded 68.5 kmph strong wind followed by Wayanad 66.6 kmph, Idukki 61.1 kmph, Thiruvananthapuram 55.5 kmph, Kannur 53.7 kmph, Pathanamthitta 53.7 kmph, Ernakulam 53.7 kmph, and Kasaragod 51.8 kmph during the 24 hours ending at 8.30 a.m. on Thursday. Neetha K. Gopal, IMD Director, Thiruvananthapuram, told The Hindu that this unusually high speed of wind has been observed since the onset of the monsoon on May 24. The speed and gustiness of the wind are higher than those normally observed during monsoon. The speed and depth of the wind influence the rain. It is not known what's driving the enhanced speed of the low-level jet, said Ms. Gopal. Global factors Though global factors such as ENSO (El Niño-Southern Oscillation) and Indian Ocean Dipole (IOD) are neutral, conditions akin to La Niña, a climate pattern characterised by unusually cold surface water temperatures in the central and eastern Pacific Ocean, are prevailing, although temperature criteria technically do not allow it to be termed La Niña. Further, the atmospheric conditions are favourable for a wet spell over Kerala, she added. Local whirlwinds Along with this, the frequency and intensity of short-lived micro-scale whirlwinds reported in the State are also unusually high this time, causing widespread damage to properties. Whirlwinds normally seem to be local, with their causes also either regional or local. One of the main reasons for the development of localised whirlwinds is the climatic changes within the region, especially the decrease in monsoon rainfall and rise in temperature. The increased temperature in the absence of rain at one place may produce gustiness while raining, according to experts.
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Business Standard
27-05-2025
- Business
- Business Standard
IMD raises monsoon rain outlook to 106% of the long-period average
The India Meteorological Department (IMD) on Tuesday raised its monsoon forecast for 2025, projecting rainfall at 106 per cent of the long-period average (LPA), up from 105 per cent predicted in April. It also expects June rainfall to be 'above normal', at over 108 per cent of the LPA. Cumulative monsoon rainfall between 105 per cent and 110 per cent of the LPA during the June-September period is considered 'above normal'. The seasonal LPA for the country, calculated over the period from 1971 to 2020, stands at 87 centimetres. The forecast for seasonal June-September rainfall carries a margin of error of +/- 4 per cent. The agency said rainfall across nearly all of India's homogenous regions — except the Northeast and parts of Bihar — was likely to be normal to above normal this year. Arunachal Pradesh, Assam and Meghalaya could see below-normal rains, according to IMD's regional outlook. 'Above-normal' June rainfall is expected to keep maximum temperatures across most of India at or below seasonal averages, with no heat waves anticipated. The month typically receives 165.4 millimetres of rainfall. Monsoon rainfall in the 'core zone' — which comprises key rain-fed agricultural regions — is also forecast to be above normal, with a 56 per cent probability of strong precipitation. Good monsoon rain across key rainfed regions in central and western India could significantly boost pulses and oilseed output, potentially reducing the country's dependence on high-cost imports. Overall, a strong and well-distributed southwest monsoon is expected to bolster kharif crop production and leave behind significant residual soil moisture for a healthy rabi harvest. Agriculture was projected to account for about 16.35 per cent of India's gross domestic product (GDP) in FY25, according to the government's second advance estimate. A robust harvest could help the government curb food inflation and provide more room for the Reserve Bank of India to cut benchmark interest rates in FY26. It may also encourage the government to be more liberal on farm exports. The central bank has forecast 6.5 per cent GDP growth and 4 per cent retail inflation for FY26. Food inflation, as measured by the consumer price index, dropped to 1.78 per cent in April, from 2.69 per cent in March. Oils & fats and fruit were the only categories with double-digit inflation in April. 'Currently, neutral El Niño Southern Oscillation (ENSO) conditions are prevailing over the equatorial Pacific regions, while the latest Monsoon Mission Climate Forecast System, as well as other model forecasts, indicates that the neutral ENSO conditions are likely to continue during the monsoon season. The Indian Ocean Dipole (IOD), which is another factor that could influence Indian monsoon, is also expected to be weakly negative,' said IMD Director General Mrutyunjay Mohapatra. He expressed confidence in the agency's 'above normal' forecast, citing improved accuracy in recent years. He said that between 2021 and 2024, IMD's average absolute error of the operational forecast was 2.28 per cent of the LPA for the second-stage forecast, and 3.15 per cent of the LPA for the first-stage forecast. 'This was well within the error range of +/- 4 per cent,' Mohapatra said. While the average absolute error of the forecast for the previous four years (2017 to 2020) of both first and second-stage forecasts was 7.5 per cent of the LPA. The southwest monsoon reached Kerala on May 24 this year, marking its earliest arrival over the Indian mainland since 2009, when it reached the southern state on May 23. The primary rain-bearing system set in over Mumbai 16 days before the usual date, making it the earliest since 1950. The southwest monsoon usually makes its onset over Kerala by June 1, reaches Mumbai by June 11, and covers the entire country by July 8. It starts retreating from northwest India around September 17 and withdraws completely by October 15. Meteorologists caution that the date of monsoon onset has no direct correlation with overall seasonal rainfall. Early or late arrival in Kerala or Mumbai doesn't necessarily determine the rain's progress or distribution elsewhere in the country, which is determined by large-scale variabilities and global, regional and local features. India saw 934.8 millimetres of rainfall in 2024 — 108 per cent of the average. In 2023, it had recorded 820 millimetres, 94.4 per cent of the average. It had seen 925 millimetres of rainfall in 2022; 870 millimetres in 2021; and 958 millimetres in 2020, according to the IMD data. (With agency inputs)
Indian Express
24-05-2025
- Climate
- Indian Express
Monsoon arrives early in Kerala, earliest onset since 2009: IMD
The southwest monsoon has made an early entrance into the Indian subcontinent this year, arriving over Kerala on Saturday — eight days ahead of its typical June 1 onset, the India Meteorological Department (IMD) said. This marks the earliest onset since 2009, when the monsoon reached the state on May 23. Over the past week, Kerala has witnessed a noticeable uptick in rainfall. The IMD declares the monsoon's arrival over Kerala based on three primary indicators: rainfall of at least 2.5 mm recorded at a minimum of 14 meteorological stations for two consecutive days, deep westerly winds extending up to 600 hectopascals, and a decline in Outgoing Longwave Radiation values below 200 watts per square meter. This early onset signals the beginning of the crucial four-month-long rainy season, vital to agriculture, water resources, and economic stability across the country. The Met department has issued warnings of extremely heavy rainfall — exceeding 205 mm in 24 hours — through Monday in Kerala and Mahe, with similar weather conditions forecast for coastal Karnataka. Adding to the turbulent weather, a well-marked low-pressure area off the Konkan-Goa coast intensified into a depression on Saturday and was expected to make landfall near Raigad in Maharashtra by evening. Squally winds and strong monsoonal currents were already prevailing across the Arabian Sea. This year, the IMD has forecast rainfall to be 'above normal,' estimating the total to be at 105 per cent of the Long Period Average (LPA) of 880 mm. Two major oceanic influences —the El Niño–Southern Oscillation and the Indian Ocean Dipole — are currently in a neutral phase, a condition expected to support monsoonal activity. The monsoon is projected to advance into the remaining parts of south peninsular and northeast India, along with additional areas of east and central India, between May 29 and June 4.
Time of India
20-05-2025
- Climate
- Time of India
Monsoon-like rain fury stuns all in Pune; orange and yellow alerts in parts of Maharashtra
Pune: May has brought unusually intense rainfall in parts of Maharashtra, with the city recording significant precipitation that makes it feel more like monsoon. Rainfall figures from 8:30am till 8.30pm on Tuesday showed Chinchwad recorded the highest rainfall at a staggering 80mm, followed by Lavale at 34.2mm and Lohegaon at 33.8mm. Tired of too many ads? go ad free now Shivajinagar registered 23.6mm of rainfall and Koregaon Park (KP) 5.5mm. The intense showers accompanied by thunder and lightning caused severe waterlogging in multiple areas across the city, further complicating the situation for residents and commuters. An IMD official explained the unusual monsoon-like pattern: "It's due to the setting of westerlies early this year. Global factors such as El Niño Southern Oscillation and Indian Ocean Dipole are favourable for a good monsoon this year. These climate patterns are showing positive indicators that could lead to above-normal rainfall during the actual monsoon season." The official added: "The current thunderstorms are pre-monsoon showers because of moisture incursion from westerlies from the Arabian Sea." As per an India Meteorological Department (IMD) forecast, conditions are likely to become favourable for monsoon onset over Kerala during the next 4-5 days. The usual date for the onset over Kerala — which marks the beginning of the four-month-long southwest monsoon over the country — is June 1. For the next few days too, parts of Maharashtra are on a yellow and orange alert for rains. Pune city is likely to see moderate rainfall as well as thunder and lightning activity during the next few days. Abhijit Modak, an independent weather forecaster, explained why it feels like the monsoon in May itself. Tired of too many ads? go ad free now "This May has been quite unique. A strong Western Disturbance extended unusually far south, reaching into the Arabian Sea. This not only brought rainfall with it but also disrupted the typical quasi-stationary high-pressure system over the north to west-central Arabian Sea. Normally, this high-pressure system drives hot northerly and northwesterly winds from Gujarat and Rajasthan towards Maharashtra. " He said: "However, this pattern was disrupted by the strong Western Disturbance. Additionally, a recent Western Disturbance also drew moisture from the south, and the seasonal line of wind discontinuity further contributed to scattered thunderstorm activity across the region over the past 10 days.". Modak said the southwest monsoon has made an early onset, arriving about a week ahead of schedule over the Indian territory of the Andaman and Nicobar Islands. "This early monsoon onset has intensified the east-west shear zone, contributing to the development of an upper air cyclonic circulation in the Bay of Bengal. All indications suggest a wetter-than-usual May for the region." IMD has issued an orange alert for ghats of Pune, Kolhapur, and Satara districts as well as other parts of Konkan and Madhya Maharashtra, warning of heavy to very heavy rainfall in the coming days. Several other districts in Marathwada and Vidarbha have been placed under yellow alert as intensifies across the region.
News18
20-05-2025
- Climate
- News18
Mumbai Monsoon Mayhem: What's Behind Early Onset Of Rains In Maharashtra? Explained
Last Updated: Orange alert has been issued for Raigad, Nashik, Pune, Satara and Kolhapur. This year, Mumbai received showers coupled with thunderstorms and gusty winds as early as May 6 Mumbai is set to witness early monsoon this month, with the city already receiving more than 85 mm of rainfall in May. The India Meteorological Department (IMD) has issued a yellow alert for Mumbai and Konkan region of Maharashtra for the next four days. Orange alert has been issued for places such as Raigad, Nashik, Pune, Satara and Kolhapur amongst others. This year, Mumbai started receiving intermittent rain coupled with thunderstorms and gusty winds as early as May 6. May has been the wettest May month since 2021. As per the Colaba coastal observatory, the city has already recorded 85.2 mm of rainfall, and the Santacruz station has logged 47.4 mm until Monday morning. Why Is Mumbai Receiving Early Rain? Mumbai is not new to unseasonal rainfall during the summer season. Why this year is an anomaly because the showers, which set in very early, have been prolonged, albeit sparse, and continued throughout the past two weeks, a report by an Indian Express report. Experts say the region experienced early showers between May 6 and May 8 due to upper-level trough formed by western disturbance. IMD Meteorologist Kashyapi told Pune Mirror, 'The monsoon is progressing swiftly. It is likely to reach Kerala by May 27—earlier than its usual date. Based on current movement, it could reach Maharashtra about five to six days ahead of schedule." An expert, Shubhangi Bhute, Director of IMD Mumbai, quoted by The Indian Express, attributed the favourable monsoon conditions to neutral El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). 'Presently, neutral El Nino as well as neutral IOD conditions are present over the Indian Ocean. These neutral conditions may contribute to good monsoon spells and also are likely to result in favourable conditions of early monsoon onset," said Bhute. ENSO is an ocean-atmospheric phenomenon that is considered one of the most important recurring natural events. It influences the Indian monsoon between June and September. What Is Monsoon Prediction For Mumbai? Traditionally, the monsoon reaches Konkan by June 5, Pune by June 10, and Mumbai by June 11. However, this year, the region is expected to receive pre-monsoon showers and early monsoon rains well in advance of these dates. Widespread rainfall expected in coming days. Several parts of Maharashtra are already witnessing rainfall activity, and this trend is expected to continue. For instance, in Vidarbha, rain forecast for the next five days; Konkan: rain likely on May 19 and 20; Central Maharashtra and Marathwada: Showers expected on May 20 and 21. Additionally, Pune, Satara, Solapur, Sangli, and the Ghat sections are likely to experience heavy rainfall with thunder, lightning, and wind speeds of 50–60 kmph over the next three days. On May 19, Ahilyanagar, Dhule, and Nashik may also receive light to moderate rain, especially in the hilly regions. Rain is expected in Palghar, North Madhya Maharashtra, Jalna, Hingoli, Nanded, and other districts on May 19, 20, and 21. As per current projections, the Southwest Monsoon is expected to enter Kerala by May 28, which is much before the normal. After this, it generally takes between 8 to 10 days for the Southwest Monsoon to reach and surpass Maharashtra. First Published: May 20, 2025, 11:33 IST
