El Nino developing slower, India monsoon to stay weak

A key measure of El Nino weather patterns eased in June, suggesting the potentially damaging condition may be developing slowly, although India's monsoon will remain weak, Australia's weather bureau said.

An El Nino, which means "little boy" in Spanish, is driven by an abnormal warming of the eastern Pacific Ocean, and creates havoc in weather patterns across the Asia-Pacific region.

The Southern Oscillation Index (SOI), a key factor in identifying an El Nino that is calculated from monthly and seasonal fluctuations in air pressure between Tahiti and Darwin, eased in June to negative 2 from a negative 5 in May, the bureau said on Tuesday.

A sustained negative SOI often indicates El Nino, a condition that can bring drought conditions to Australia's farmlands, weaken the Asian monsoon critical for Indian crops, stir up storms in the Gulf of Mexico and cause flooding in Latin America.

"Minus 10 is an often used threshold level and it just got to there a few times, but it hasn't been sustained at that level," Sam Cleland, author of the Bureau of Meterology's weekly Tropical Climate Note, said on Tuesday.

"I don't think we'd make the call just yet that we have an El Nino event in place," he said ahead of the bureau's El Nino update on Wednesday.

Its last report said an El Nino was very likely in 2009 and may be declared in coming weeks. The last El Nino was in 2006.

David Palmer, a meteorologist at private forecasting firm the Weather Company says indicators suggest there is a 60 percent chance of an El Nino developing in August, the month when it usually can be determined whether the weather pattern exists.

"We've been suggesting for some time now that there is an El Nino developing but it is not until August that you can say that for sure," said Palmer.

"If I were a betting man I would be putting my money on it."

But Cleland said the Pacific trade winds, another key El Nino factor, had also weakened in June.

"The equatorial Pacific Ocean continues to develop into a more El Nino like pattern," said Cleland, manager of climate services at the bureau's Darwin office.

"To call an El Nino or not is difficult and it takes a number of parameters over a sustained period. The formal definition of an El Nino often occurs in hindsight," he said.

The last severe El Nino in 1998 killed more than 2,000 people and caused billions of dollars in damages to crops, infrastructure and mines in Australia and Asia. It came in the middle of the Asian crisis that roiled financial markets.

India, one of the world's biggest producers and consumers of everything from sugar to soybeans, is already experiencing a weaker annual monsoon. Its faltering sugar crop has helped drive world prices of the commodity to their highest in three years.

India's monsoon will remain weak according to the latest Madden-Julian Oscillation (MJO) index, which gauges the eastward progress of tropical rain, Cleland said. It was too early to get a read on the potential intensity of a new El Nino, he added.

"There's no strong indication at this stage of what level of impact this ENSO event could have," he said, adding that some weak El Ninos have had severe impacts on Australia rainfall, while stronger El Ninos have only had marginal impacts.

Original from:: http://in.reuters.com/article/economicNews/idINIndia-40861720090707?pageNumber=3&virtualBrandChannel=11584

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Chennai - No rain today and expect no rain for rest of the evening... going to be a warm evening with temperature at 30 deg.

Rainfall on 5-Jul-09:: Bhatkal (Uttara Kannada dt) and Agumbe 18 each, Kottigehara (Chikmagalur dt) 17, Kollur (Udupi dt) 15 cm.

Chennai - Records high of 37.7°C (1:49pm)

Monsoon lash Dakshina Kannada

After prolonged delay, monsoon intensified in Dakshina Kannada district since Saturday. Both coastal and interior areas of the district received heavy rain on Saturday. The department of metrology observatory at Panambur recorded 10.18 cm of rainfall. Among the five taluks, Bantwal received highest at 11.26 cm followed by 9.56 cm rain at Belthangady. Rainfall recorded in other taluks include 7.9 cm in Puttur, 7.7 cm in Sullia and 8.16 cm in Mangalore.

Monsoon rains seen retaining vigour until mid-July

The monsoon has entered a vigorous phase not witnessed till date during the season, with central and adjoining peninsular India too expected to come under enhanced rain cover from early this week.

This is despite the poor credentials of a concurrent rain-driving system developing in the Bay of Bengal, where model forecasts see no anchor 'low' materialising for another week.

But the strong flows ordained by a benign Madden-Julian Oscillation (MJO) wave are enough to sustain the monsoon strength until July 15, say model forecasts.

ARABIAN SEA 'LOW'

The west coast would continue to be battered by waves of torrential rainfall closing in one after the other, culminating in the formation of a 'low' over northeast Arabian Sea midway through.

The system may move away from coast for sometime, only to get snaffled by an expanding trough from a prospective and well-endowed 'low' materialising in the Bay by the end of the week (around July 12).

This phase could launch monsoon towards another peak replete with the prospect of a mid-tropospheric cyclonic (MTC) circulation, a prolific generator of sustained rainfall, revealing itself right above Gujarat.

An MTC is known to generate much more rain in time and space than a conventional monsoon 'low' or depression is capable of, eve while being blessed with enhanced staying power.

South Gujarat and Konkan coast, including Mumbai and central India, would do well not to lower its guard and ready themselves to deal with any situation likely arising from enhanced rains and flood conditions.

IOD BOOSTER

Monsoon rains from a friendly MJO wave may get further boosted in the context of signs of a positive Indian Ocean Dipole (IOD) event marked by positive sea-surface temperature anomalies for southwest Indian Ocean.

India Meteorological Department (IMD) said in an update on Sunday that the monsoon has been an 'active' phase overnight in sub-Himalayan West Bengal, Sikkim, Orissa, Konkan, Goa and coastal Karnataka.

But it was subdued over Bihar, west Uttar Pradesh, Haryana, Punjab, east Rajasthan, Telangana and Rayalaseema, which is reflective of how rain coverage can falter if no anchor 'low' is available in the Bay.

The IMD said that rainfall occurred at most places over the west coast, including Mumbai, and at many places over central and northeast India, interior south peninsula and Orissa during the past 24 hours.

In its outlook for the next few days, it said that the active/vigorous phase of the monsoon is likely to continue over west coast during the next 2-3 days.

Rains would become further entrenched over central and adjoining peninsular India from Tuesday onwards, apparently after an upper air cyclonic circulation spins over into land and moves west.

The wave of rains is likely to merge with a counterpart coming from the opposite direction and lead to sustained rainfall over central India, west Maharashtra and the west coast for the rest of the week.

This phase may also see the run-up to the initiation of the long-delayed anchor 'low' in the Bay by the weekend. It could get a move to the west-northwest along the seasonal monsoon trough over land, bringing monsoonal rains into the northwest.

On Sunday, the crucial monsoon trough over land lay extended from Anoopgarh, Alwar, Fatehpur, Daltonganj, Digha and southeastwards into east-central Bay of Bengal.

OFFSHORE TROUGH

To the peninsular west, the rain-making offshore persisted from Konkan coast to Kerala coast, and will continue to cause widespread rainfall with heavy to very heavy falls at a few places over west coast for another 4-5 days.

Numerical weather prediction models suggest fairly widespread rainfall activity with isolated heavy to very heavy falls for east India, especially West Bengal, Sikkim, Orissa, as well as for the northeast during the next 2-3 days.

A warning valid for the next two days said that heavy to very heavy rainfall are likely at a few places with isolated extremely heavy fall exceeding 25 cm over Konkan and Goa.

Heavy to very heavy rainfall has been forecast at a few places over coastal Karnataka also during this phase. Isolated heavy to very heavy rainfall is likely over the northeast, West Bengal, Sikkim, Orissa, Kerala and Lakshadweep.