Forecast: La Niña intensity shifts to ‘moderate’

MANILA, Philippines — Climate experts in the United States have downshifted their La Niña forecast to “mode­rate” from “potentially strong,” based on indicators monitored in November.

Still, countries in the western Pacific Ocean, including the Philippines, will continue to expect higher than normal rainfall over the next three months.

The latest monthly advisory from the United States Climate Prediction Center (CPC) states that La Niña persisted in November, as indicated by well below-average sea surface temperatures.

The CPC added that the atmospheric circulation over the tropical Pacific Ocean remained consistent with La Niña.

The opposite of El Niño, La Niña typically increases rainfall over Southeast Asia including the Philippines from October to February and even up to May.

“Supported by the latest forecasts from several models, the forecaster consensus is for a moderate strength La Niña during the peak November-January season,” the agency said.

“La Niña is likely to continue through the Northern Hemisphere winter 2020-21 (about 95 percent chance for January-March), with a potential transition during the spring 2021 (about 50 percent chance of neutral during April to June,” it added.

“Neutral” means the absence of both La Niña and El Niño.

In the CPC’s previous advisory issued in November and based on October data, La Niña was assigned a 95-percent probability of continuing to prevail in the January to March period and 65 percent to linger on in March to May.

A series of typhoons that formed and hit the Philippines—as La Niña went full-blown in the previous several weeks—have caused devastating floods in various parts of the country, particularly Cagayan Valley.

On the other hand, the rains raised the stock of raw water at the Angat Dam in Bulacan province—the main source of water for Metro Manila and adjacent provinces—past the normal high level of 212 meters above sea level (masl).

As of the morning of Dec. 11, water level at Angat was pegged at 212.81 masl. The level has been above 212 masl since Nov. 30. —RONNEL W. DOMINGO