Latest news with #Madden-JulianOscillation
Indian Express
01-07-2025
- Climate
- Indian Express
What caused early national coverage by monsoon this year?
The southwest monsoon covered the entire country on June 29, nine days ahead of its normal schedule of July 8. Since 1960, this was only the tenth occasion when the monsoon completed the national coverage in June. What led to the monsoon's rapid progress? This year, the monsoon onset was early as well. It arrived in Kerala on May 24, eight days before the usual date schedule of June 1. This happened due to a range of different reasons including the active phase of the Madden-Julian Oscillation (MJO) — a moving system of wind, cloud and pressure that brings rain as it circles around the equator — in mid-May. After the onset, the monsoon progress largely remained ahead of its normal schedule over south peninsular, east and northeast India, and near normal over the northwest. However, it was slightly delayed over the central India region. According to the India Meteorological Department, the monsoon's rapid progress was driven by: LOW PRESSURE SYSTEMS: India witnessed the development of five low pressure systems over different regions in June. These systems are essentially areas where the atmospheric pressure is lower than the surrounding regions. Given that winds travel from high pressure to low pressure areas, these systems act like a magnet, pulling in moisture-laden winds, helping trigger rainfall, and pushing the monsoon inland. ACTIVE PHASE OF MJO: Like in May, June also witnessed an active phase of the MJO. In this phase, the MJO brings more clouds to south of India, which are then carried northwards by the monsoon winds, leading to enhanced rainfall. MONSOON TROUGH'S POSITION: A monsoon trough is an elongated low pressure area stretching from northwest India to the Bay of Bengal, whose position affects the monsoon conditions over the country. In June, as it remained largely to the south of its normal, it drew moisture-laden air, bringing in the monsoon early over the entire country. NEUTRAL PHASE OF ENSO & IOD: The southwest monsoon is affected by two other factors, El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD). ENSO — a climate phenomenon characterised by changes in sea temperatures along the central and eastern tropical Pacific Ocean, accompanied by fluctuations in the atmosphere overhead — has three phases, El Niño, La Niña, and neutral. While El Niño suppresses monsoon, La Niña and neutral lead to stronger and normal rainfall respectively. In June, ENSO was in the neutral phase. IOD, which is the difference in sea surface temperatures (SSTs) between the eastern and western regions of the Indian Ocean, also has three phases, positive, negative, and neutral. While a positive IOD leads to more rainfall, a negative phase results in less rainfall. A neutral IOD has minimal impact. In June, IOD was in a neutral phase. How was the rainfall performance in June? In June, the all-India average rainfall stood at 180 mm, which was quantitatively 9% above normal, according to the IMD. This year, the deficit rainfall trend observed during June since 2022 was discontinued. Over central India, June's average rainfall was 24.8% above normal — a trend which was seen for the first time since 2022. The region received 212.6 mm of rainfall. However, east and northeast India continued to suffer a rainfall deficiency for the third consecutive year. It recorded 272.9 mm of rainfall, which was 16.9% below normal. No significant rainfall trend was observed over the peninsular and northwest India regions for June. State-wise rainfall figures suggested that, for the first time since 2019 and 2020, Manipur (242.7 mm) and Mizoram (466.9 mm) respectively recorded normal rainfall this June. However, the month ended with below normal rainfall across Arunachal Pradesh, Assam, Meghalaya, Sikkim, Bihar, Delhi, Chhattisgarh, Andhra Pradesh, Telangana and Lakshadweep. More than 80% of meteorological subdivisions received normal or above normal rainfall in June, including those which were significant for kharif sowing.
Yahoo
27-06-2025
- Climate
- Yahoo
National Hurricane Center eyes new Central American disturbance as tropical weather season progresses
MIAMI - The National Hurricane Center is monitoring an area of disturbed weather over Central America that is expected to briefly move over the Bay of Campeche in the coming days. While the odds of tropical development remain low so far, forecasters expect the area of showers and thunderstorms to bring beneficial rainfall to parts of drought-stricken Mexico. The Bay of Campeche is known for rapid spin-ups of tropical cyclones due to warm sea surface temperatures and favorable terrain, but several factors are working against significant development in this case. Forecast models and the current phase of the Madden-Julian Oscillation suggest that environmental conditions will likely inhibit tropical cyclone formation. Even if the system were to organize, any impacts would remain well south of the U.S.–Mexico border, near Tampico, Mexico, which is roughly 300 miles south of the Lone Star State. 2025 Atlantic Hurricane Season Guide: Here's What To Know About The Tropics This Year So far, the 2025 Atlantic hurricane season has been unusually quiet, with the basin's Accumulated Cyclone Energy, or what is commonly referred to as ACE, sitting at a meager 0.2 units. ACE is a metric used by forecasters to quantify the strength and duration of tropical cyclones, with greater values indicating stronger, longer-lasting systems. According to data compiled by Colorado State University, the 2025 ACE value is more than 90% below average for the Atlantic Ocean, Caribbean Sea and Gulf of America. Several factors have contributed to the suppressed activity in the Atlantic basin, including above-normal surface pressures, increased atmospheric stability and a lack of moisture over the tropics. Adding to the suppression is the heightened amount of tropical activity in the eastern Pacific, which is running close to 30% above normal. The string of recent developments, including the potential future formation of Tropical Storm Flossie, are believed to be contributing to a more hostile upper-level environment over parts of the Gulf and Caribbean. Bryan Norcross: Tropical Delay To Extend Into July The next name on the Atlantic season list is Barry, but as of now, there are no indications that a named storm will form in the immediate future. The climatological peak of hurricane season occurs in mid-September, with tropical cyclone formation continuing into early article source: National Hurricane Center eyes new Central American disturbance as tropical weather season progresses
USA Today
21-06-2025
- Climate
- USA Today
The 2025 hurricane season is off to a perplexing start
The eastern Pacific Ocean has seen a historic run of activity as the Atlantic remains dormant. Forecasters point to perplexing planetary phenomenon. Hurricane Erick formed June 18 in the eastern Pacific Ocean, becoming the fifth named storm of the eastern Pacific season to date – a flurry of activity in sharp contrast with the tepid start to hurricane season in the Atlantic. By some counts, the Eastern Pacific has been on a historic run, recording five named storms before the third week of June for the first time on record, said WPLG-TV 10 meteorologist Michael Lowry via his email newsletter June 17. See photo gallery: Photos show impact of Hurricane Erick after landfall along Mexico Pacific coast The activity was due in part to a large-scale climate pattern known as the Madden-Julian Oscillation, which is an eastward-moving disturbance of clouds, rainfall, winds, and pressure. It traverses the planet in the tropics and returns to its initial starting point in 30 to 60 days, according to the National Oceanic and Atmospheric Administration. It, along with other obscure patterns such as Rossby and Kelvin waves, influence weather, including hurricane formation, around the globe. What does the fast start in the Pacific mean for the Atlantic hurricane season? Although some storms can cross over Central America from one ocean to the other, there isn't really an overall connection in activity, AccuWeather hurricane expert Alex Da Silva told USA TODAY. Colorado State University meteorologist Phil Klotzbach agreed, noting in an email to USA TODAY that "there's not a lot that we can say tying in the fast start to the eastern North Pacific to what the season may portend for the Atlantic. "The relationship between Atlantic hurricane activity and eastern North Pacific hurricane activity just off of the west coast of Mexico (as we've seen this year), is fairly weak," he said. Thus, the early activity in the Pacific isn't likely a harbinger of storms to come in the Atlantic. DaSilva said the Madden-Julian Oscillation pulse made it to the eastern Pacific but fell apart before reaching the Atlantic. What led to all the storms in the eastern Pacific so far this season? The pulse of storminess that moves eastward around the globe's tropical regions – the Madden-Julian Oscillation – "helped to kick off a flurry of storm activity in the eastern Pacific," Lowry said. Specifically, the MJO's enhanced phase, which is characterized by increased rainfall and rising air, creates an environment more conducive for hurricane development, while the suppressed phase has the opposite effect. Atlantic remains quiet ‒ for now While the eastern Pacific is running about a month ahead of schedule with all of its activity, the Atlantic is on track for a typical to even slow start, Lowry said. "Models are muted on any development chances for the basin into at least the middle part of next week." The next chance of widespread storminess returning to the tropical Atlantic won't be until around the first week of July. Other planetary phenomena at play A Kelvin wave, formally known as a convectively coupled Kelvin wave, is thought to have interacted with a Rossby wave over the Americas, contributing to limited tropical development in the Atlantic basin, but creating a favorable pattern that helped spawn the formation of both Dalila and Erick to the south of Mexico, according to the Climate Prediction Center. Kelvin waves, which can extend up to 4,000 miles in length and be thousands of miles wide, move along the equator in the same direction as the Madden-Julian, only faster, said Quinton Lawton, a post-doctoral fellow at the National Center for Atmospheric Research in Colorado. Perturbations inside the waves can encourage thunderstorms and rainfall. Scientists have only recently begun to understand more about how planetary phenomena work together to spawn or suppress tropical storms and hurricanes. 'It turns out that these waves actually end up being really important for tropical cyclones,' Lawton said. Kelvin waves and Rossby waves originate from energy in the atmosphere and then move along the equator. As the Madden-Julian circumnavigates the globe, its interaction with these atmospheric waves can encourage storm formation.
News18
12-06-2025
- Climate
- News18
Monsoon Arrived 8 Days Early In Kerala, Why Has It Progressed So Slow Since Then?
Last Updated: By early June, the monsoon's pace slackened. Rainfall eased in most southern and northeastern parts of the country. Even flood-affected areas in the Northeast began to dry up. The southwest monsoon, a lifeline for agriculture and water needs, arrived with a bang but has since entered a puzzling pause. When it reached Kerala on May 24, eight days ahead of schedule, it sparked widespread celebration across the country. The India Meteorological Department (IMD) called it the earliest onset since 2009. Hopes soared as rain lashed southern parts of the country. But now, deep into the second week of June, the monsoon's momentum has mysteriously stalled, leaving much of the country grappling with heat and uncertainty. The monsoon's early entry wasn't just confined to Kerala. It simultaneously swept into Lakshadweep, Mahe, southern Karnataka, parts of Tamil Nadu, and Mizoram, an unusually widespread onset that delighted meteorologists and farmers alike. The last week of May saw intense rainfall in Kerala, with red alerts issued in multiple districts due to flooding and landslides. But by early June, the monsoon's pace slackened. Rainfall eased in most southern and northeastern parts of the country. Even flood-affected areas in the Northeast began to dry up. According to private forecaster Skymet, the monsoon's advancement has hit a temporary wall, particularly in northeastern states. Meteorologists attribute the sluggish progress to a mix of global atmospheric and oceanic shifts. The early burst was helped by favourable conditions like the active phase of the Madden-Julian Oscillation (MJO), a moving pulse of cloud and rainfall over the tropics, and a neutral Indian Ocean Dipole (IOD). The absence of El Nino, a phenomenon that typically suppresses monsoon rains, also worked in the country's favour. But June brought a shift. The MJO lost steam, weakening the systems that propel the monsoon northward. In addition, the seasonal low-pressure area that usually drives the monsoon's inland advance remains south of its expected position, restricting rain to southern coastal regions. Despite the slowdown, the IMD has issued a new round of forecasts that may bring hope. Between June 11 and 17, heavy to very heavy rainfall is expected to return to Kerala and Lakshadweep. Wind speeds may reach 60 km/h, and isolated areas could see extreme rain from June 14 to 17. However, the monsoon remains sluggish over Maharashtra, Goa, and much of the Northeast. The early-season flooding in Kerala is giving way to heat and humidity, a pattern mirrored in several parts of the country. Will Monsoon Regain Momentum? The IMD remains optimistic about the broader monsoon season. It has projected overall rainfall at 105% of the long-period average, an encouraging sign for agriculture and the economy. Yet, weather experts caution that early onset does not guarantee a successful or well-distributed monsoon. In 2009, the monsoon had also arrived early, on May 23, but June that year saw a severe 48% rainfall deficit, and August followed with a 27% shortfall. The memory of that anomaly is prompting meteorologists to urge caution amid early excitement. First Published: June 12, 2025, 14:25 IST
New Indian Express
05-06-2025
- Climate
- New Indian Express
CWRDM proposes immediate steps to face monsoon crisis in Kerala
THIRUVANANTHAPURAM: With the southwest monsoon arriving earlier than usual and bringing unusually heavy rain, the Centre for Water Resources Development and Management (CWRDM) has issued urgent recommendations to tackle potential flooding and landslides in Kerala. The state witnessed one of its earliest monsoon onsets in recent years. According to CWRDM, this year's pattern—marked by intense rainfall in short bursts followed by dry spells—highlights the growing need for improved disaster preparedness and smarter water management. In just one week, from May 24 to 31, Kozhikode recorded 620 mm of rainfall—nearly 28% of the region's average monsoon total. Daily rainfall during this period crossed 60 mm, sparking fears of flash floods, waterlogging, and landslides, especially in hilly regions. 'Traditionally, Kerala's monsoon sets in around June 1. But since 1970, nearly half of the monsoons have begun in late May,' said CWRDM executive director Manoj P Samuel. 'This year's early onset is among the earliest ever—second only to May 18, 1990,' he said. Experts link this shift to warming sea surface temperatures in the Arabian Sea, stronger cross-equatorial winds, and global atmospheric changes such as the Madden-Julian Oscillation.
