Tropical Storm Nokaen Raises Lahar Risk at Mayon Volcano

The first tropical cyclone of the year, Tropical Storm Nokaen, locally named Ada, is posing fresh risks for communities around Mayon Volcano in the Philippines. Authorities have warned that the storm could trigger dangerous lahars and muddy streamflows due to heavy rainfall, compounding the ongoing volcanic hazards on Luzon island.

Storm Intensity and Projected Track

The state weather bureau, PAGASA, said Tropical Storm Nokaen is packing maximum sustained winds of 65 kilometres per hour near its centre, with gusts reaching up to 80 kilometres per hour. The system is moving slowly northward over the Philippine Sea, east of Eastern Visayas, and is expected to affect the eastern coast of southern Luzon over the weekend.

Heavy Rainfall Threat Near Mayon Volcano

According to PAGASA’s tropical cyclone advisory, Nokaen could bring heavy to intense rainfall ranging from 100 to 200 millimetres. Areas surrounding Mayon Volcano in Albay province are particularly vulnerable due to the volcano’s steep slopes and loose volcanic material. Such rainfall increases the risk of flash floods and sediment-laden flows.

Phivolcs Warning on Lahars

The Philippine Institute of Volcanology and Seismology warned that intense rainfall from Nokaen could generate syn-eruption lahars in rivers and drainage channels around the volcano. These flows may incorporate loose material from new pyroclastic density current deposits from Mayon’s ongoing eruption, which has persisted since January 1. Phivolcs cautioned that hot lahars could cause scalding on contact, posing severe and potentially life-threatening risks.

Imporatnt Facts for Exams

• Lahars are volcanic mudflows composed of water and volcanic debris.
• Mayon Volcano is one of the most active volcanoes in the Philippines.
• PAGASA is the official weather forecasting agency of the Philippines.
• Phivolcs monitors volcanic and seismic activity in the country.

Impact on Communities and Emergency Response

Phivolcs also warned that older eruption deposits on Mayon’s southwestern slopes could be remobilised as non-eruption lahars, threatening downstream communities through inundation, burial and boulder impacts, potentially reaching coastal areas. Thousands of residents in Albay province have already been displaced due to volcanic unrest. Officials cautioned that heavy rains from Nokaen could worsen conditions in evacuation centres and complicate relief operations, urging residents to remain alert for further advisories.