Pagasa testing new rain alert system

MANILA — Weather officials have begun testing new equipment that can forecast the amount of rainfall brought by weather disturbances and issue more reliable flood warnings in various areas.

Dr. Flaviana Hilario, head of the research and development division of the Philippine Atmospheric, Geophysical and Astronomical Services Administration said the rainfall warning system will initially be tested in Metro Manila and will be ready by June, the start of the rainy season.

The Philippines currently has no warning mechanism for rainfall.

What it has is a four-level warning signal for tropical cyclones.

The typhoon warning system measures the wind strength of an incoming typhoon, while the rainfall warning system will measure the amount of water that is expected to fall on a specific day and site, Hilario said.

The alert system for rainfall would enable communities to plan ahead and better anticipate flash floods and river overspills even if there is no typhoon in sight, Hilario said.

For average days, rainfall alerts could help residents plan their day’s activities.

Pagasa administrator Nathaniel Servando said the rainfall alert system should be ready by June, the start of the wet season in the Philippines.

“We have seen that the rains have become damaging even if there is no typhoon. This is one of the considerations here,” Servando said.

Servando said Pagasa is studying the rain alert system used by the Hong Kong Observatory, which  has three alert levels that each correspond to a certain amount of rain.

This is more detailed than the usual forecast of light, moderate of heavy rains.

In cases of typhoons, the agency will also be able to gauge the expected downpour, which is measured in millimeters per hour.

Aside from the total rainfall t hat the clouds are carrying, Servando said they would also like the rainfall alert information to include data such as the probability of precipitation, possible hazards, areas affected, and estimated amount of rain in the next few hours.

Hilario said Pagasa would be fine tuning the warning scheme once it is up and running to include more data.

Hilario said it would be useful for communities and local disaster councils to match the weather information from Pagasa with the geohazard maps from the Environment department when responding to risks and disasters, Hilario said.

Officials said the rainfall warning system was one of the topics discussed with President Aquino and the Cabinet Cluster for Climate Change last month, just after Tropical Storm Sendong devastated Cagayan de Oro and Iligan cities, which were caught off guard by the rains. Inquirer