Actually, La Niña has been in the country since Feb. 20 this year when Science Secretary Estrella Alabastro made the official declaration of the weather phenomenon’s existence.

According to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), La Niña is characterized by "above normal rainfall."

The weather phenomenon is defined as "cooler than normal sea-surface temperatures in the central and eastern equatorial Pacific Ocean that impact on global weather patterns."

PAGASA said La Niña occurs "every three to seven years and can persist for as long as two years."

To prepare against possible incoming disasters brought about by La Niña, PAGASA has formed a committee called the National Disaster Action Committee.

The committee will lead in the production of multi-hazard maps showing areas prone to floods, storm surges, extreme temperature, earthquake, and other geological and hydrometeorological hazards, according to PAGASA Weather Branch chief Nathaniel Cruz.

He said the committee has been tasked to undertake an extensive information campaign to enable the people using the hazard maps to understand them.

He said the committee is going to establish an early warning system and stockpile the necessary supplies in the provinces expected to be hit the hardest by La Niña.

"Maglalagay ng supplies in easily-accessible areas in case of landslides and flashfloods," Cruz said, adding that this will continue up to June this year, the month the weather bureau expects La Niña to last.

Cruz said the committee is headed by DoST Undersecretary Graciano Yumul Jr., who is also the officer-in-charge of PAGASA, and Philippine Institute of Volcanology and Seismology director Dr. Renato Solidum; Department of Environment and Natural Resources (DENR) Undersecretary Manny Geroche and Dr. Mario Aurelio of the DENR Mines and Geosciences Bureau.

Meanwhile, National Defense Secretary and concurrent National Disaster Coordinating Council (NDCC) Chairman Avelino Cruz Jr. said the government has three mediumterm flood control projects in preparation for the onset of La Niña.

These include Phase III of the Mt. Pinatubo Hazard Mitigation amounting to P4.8 billion; the Cagayan River Flood Control Project amounting to P2.39 billion and the Caraga Flood Control Project, where monetary figures are still being studied by the government, led by the Department of Public Works and Highways (DPWH).

According to Cruz, the projects are expected to be completed from 18 to 26 months, adding that these are all "priority" projects of the government.

Cruz said the newly created Task Force La Niña, which includes several agencies of the Executive branch, is preparing for the construction of bridges and dikes as well as measures to prevent flood-related diseases like respiratory infection.

Rosalina de Guzman, supervising weather specialist at the PAGASA Climatology and Agrometeorology Division, said the country does not have its own equipment to monitor sea-surface temperature (SST) in the tropical areas of the Pacific Ocean that could detect the development of the La Niña phenomenon.

"Nagde-depend tayo sa United States, Australia and Japan dahil may satellite and sensor sila na nakade-detect ng SST (seasurface temperature) sa tropical Pacific Ocean," she said.

These international climate centers include the USA’s International Research Institute and National Oceanic and Atmospheric Administration; Australia’s Bureau of Meteorology, and Japan’s Tokyo Climate Center.

Meanwhile, in a bid to further improve its weather forecasting capability, PAGASA said it is now working on its "Grand Plan" starting this year. A part of this plan includes the "10 by 2010 proposal," which seeks to install 10 Doppler radars by 2010.

Initially, the weather bureau will be putting up two brand- new Doppler radars in Subic, Olongapo City and Tagaytay City this year that would cover the Metro Manila area and other nearby towns and cities.

Yumul added that PAGASA is currently "in the middle of a negotiation with the Japan International Cooperation Agency for the acquisition of three more Doppler radars that would be installed next year amounting "close to a billion pesos."

These Doppler radars would be installed in Virac, Catanduanes; Guiuan, Eastern Samar; and Aparri, Cagayan, which are all currently providing public weather forecast using the surveillance band (S-band) radar capability.

In addition, Yumul said, the three S-band radars from the above-mentioned areas would be transferred to Davao, Cagayan de Oro and in Busuanga, Palawan for a much-improved weather forecasting capability in the southern Philippines.

Meanwhile, Yumul said P17 million has been given by the United States and the World Meteorological Organization (WMO) for the "repair and rehabilitation" of the Laoag upper air observation center in Ilocos Norte this year while P18 million is reserved for the repair of the PAGASA upper-air observation center in Legaspi City.

"So there will be two (upper-air observation centers) working this year," he said.

According to Engr. Catalino Davis, PAGASA Field Operations chief, PAGASA has a total of six upper-air observation centers stationed in Puerto Princesa City, Palawan; Legaspi City, Albay; Cebu; Tanay, Rizal; Quezon City and Laoag City.

Plans to upgrade the Baler and Baguio Radar and Synoptic Stations from S-band to Doppler radar capability are also being undertaken, Yumul said, adding that the installation of a World Area Forecasting System (WAFS) in Cebu is also being pursued by PAGASA.

"So, pag nasira and WAFS in NAIA (Ninoy Aquino International Airport) at ang S-band radar in Guiuan, Eastern Samar, it will serve as a second line of defense," Yumul said.

Alabastro earlier said that aside from its other functions, Doppler radars have the capability to estimate rainfall. This would enable nearby towns and cities to be given sufficient warning against floods.

With its 200-kilometer range, the Doppler radars would further strengthen the detection of strong winds, velocity and amount of rainfall, and the amount of moisture in cloud formation, Yumul said.

Last year, the weather bureau has rehabilitated and upgraded the five S-band radars in Aparri, Virac, Catanduanes; Guiuan, Baler, and Baguio City.

De Guzman said this year’s La Niña is "peculiar" due to its "unusual'' development.

"Usually, July nagde-develop ang La Niña. Ngayon, late nag-develop kaya very uncertain ang impacts," she said.

The weather specialist, however, said the weather phenomenon is not experienced in the country alone but in other countries like China, Japan, Indonesia and Australia.

According to De Guzman, the worst case of La Niña in the country was felt in 1999 to 2000, which was categorized as a "strong" La Niña phenomenon.

She, however, said there had been a forecast coming from the international climate centers that after La Niña, the country would have normal weather conditions because the sea surface temperature in the tropical Pacific Ocean would go back to its "neutral" condition.

For the next few months, however, PAGASA said key areas identified to have bigger amount of rainfall due to La Niña must brace themselves against incoming disasters.

Hilario said that for this month of March, the areas expected to have above normal rainfall include Isabela, Rizal, Aurora, Camarines Sur, Albay, Sorsogon, Masbate, Eastern Samar, Southern Leyte, Bohol, Surigao del Norte, and Davao Oriental

For the month of April, heavy rainfall is expected over Quezon province, Laguna, Eastern Samar, Southern Leyte, and Eastern Mindanao.

By May, extreme Northern Luzon, Quezon province, Cavite, Rizal, the Bicol region, Samar, Leyte, Central Visayas, Eastern Mindanao, and Southern Mindanao would have to brace themselves for heavy rainfall.

Earlier, Dr. Hilario said that if present weather conditions would continue for the next three months, the country should expect a "drier southwest monsoon" similar to the weak La Niña phenomenon from 1995 to 1996.

However, if the weather pattern continues up to the next six months, "We’ll have a wetter southwest monsoon," she said, adding that it would be similar to the "strong" La Niña phenomenon which started last 1998 and extended up to 2000.

Other La Niña events experienced in the country were in 1983 to 1984, October 1995 to March 1996 and from July 1998 up to 2000.