Rains brought by the southwest monsoon have helped reduce fine particle pollution over parts of Luzon as haze linked to wildfires in Indonesia continued to affect the region, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa).
Pagasa said rainfall lowered pollutant concentrations by helping remove particles from the atmosphere. They added that prevailing winds were also pushing much of the haze toward the Visayas and Mindanao.
Environmental Management Bureau monitoring stations across Metro Manila recorded relatively low PM2.5 levels ranging from 20 to 41 as of 6 a.m. Friday.
In Central Luzon, stations in Meycauayan, Bulacan, and Santa Cruz, Zambales, posted PM2.5 readings between 17 and 35 as of 9 a.m.
PM2.5 refers to microscopic airborne particles measuring 2.5 micrometers or smaller that can penetrate deep into the lungs.
Manalo said the cleaner readings could change once conditions turn drier, since pollutants may disperse again and potentially reach Luzon depending on wind direction.
The southwest monsoon was expected to continue bringing rain over western Luzon on Friday, although PAGASA said rainfall could weaken over the weekend.
Most of the Visayas and Mindanao were expected to see only isolated or scattered showers, meaning any improvement in air quality from rainfall would likely be limited to areas that actually receive rain.