The weather bureau on Wednesday put several areas in Northern and Eastern Samar under Storm Signal No. 1 after Tropical Storm “Ambo” intensified slightly.
The Philippine Atmospheric, Geophysical and Astronomical Services Administration said "Ambo" was last tracked 410 kilometers east of Borongan City in Eastern Samar.
The storm had maximum sustained winds of up to 85 kilometers per hour near the center and gustiness of up to 105 kph and was heading north-northwest at 15 kph.
Weather specialist Meno Mendoza said the areas under Signal No. 1 were Jipapad, Maslog, Arteche, San Policarpio, Oras, Dolores, Can-avid, Taft, Sulat, San Julian and Borongan City in Eastern Samar and the towns of Lapinig, Gamay, Mapanas, Palapag, Laoang, Catubig and Las Navas in Northern Samar.
Strong to near-gale force winds will begin affecting those areas on Thursday afternoon.
"Ambo" is expected to further intensify as it approaches Eastern Visayas and may make landfall over Bicol on Friday, Mendoza said.
Officials warned that prolonged heavy rainfall could generate post-eruption lahar on the major channels draining Mayon Volcano by incorporating loose material from the thick deposits of ash from the January-March 2018 eruption. Joel E. Zurbano and Rio N. Araja
The Philippine Institute of Volcanology and Seismology recommended increased vigilance and readiness of the communities in the pre-determined zones of lahar hazards in Mayon Volcano.
Senator Sherwin Gatchalian called on the government to prepare contingency measures now that "Ambo" had intensified into a tropical storm, the first storm to enter the country this year.
He said some parts in Metro Manila recently experienced power outages despite assurances from Meralco that the power grid would be stable and have sufficient energy supply all throughout summer.
He said the Energy department and the National Electrification Administration should take contingency plans to avert any possible power outages during the storm.