Tropical Storm Vongfong, First Named Storm of the Year in the West Pacific, Heading to the Philippines

Tropical storm Vongfong is moving west-northwest and a thunderstorm advisory has been issued over parts of the central region of Luzon, the largest and most populous island of the Philippines which is home to the capital Manila.

Heavy rainfall is expected later today and Thursday, while gale force winds are possible in some parts of the Eastern Visayas and Bicol regions by tomorrow and Friday morning, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) reports.

Tropical storm Vongfong (locally known as "Ambo") is the first tropical cyclone of the Northwestern Pacific Ocean typhoon season, according to NASA. It is also reportedly the first named storm of the year in the Western Pacific. The storm is expected to intensify as it approaches the Eastern Visayas and Bicol regions, PAGASA warns.

A thunderstorm advisory was issued on Wednesday, with moderate to heavy rain showers, accompanied by lightning and strong winds, expected today in parts of the Central Luzon provinces of Bataan, Zambales and Pampanga, according to a post on the official Twitter account of PAGASA.

"All are advised to take precautionary measures against the impacts associated with these hazards which include flash floods and landslides," the Tweet by PAGASA said.

Moderate to heavy rainfall is forecast for the Eastern Visayas region as well as the provinces of Catanduanes, Albay and Sorsogon in the Bicol region of Luzon, and on the island province of Masbate.

"Residents in these areas are advised to take precautionary measures, coordinate with local disaster risk reduction and management offices, and continue monitoring for updates," PAGASA states on its website.

"Flooding and rain-induced landslides may occur in highly to very highly susceptible areas during heavy or prolonged rainfall," it adds.

Strong to gale force winds may affect the Eastern Visayas provinces of Northern Samar and Samar as well as the northern portion of the Eastern Samar province on Thursday afternoon. The same level of winds may also affect Sorsogon, Catanduanes, the southern portion of Albay and Ticao Island of the Masbate province on Friday morning, PAGASA warns.

"Rough seas will be experienced over the eastern seaboard of Bicol Region and the northern and eastern seaboards of Eastern Visayas today. Sea travel is risky over these areas," PAGASA states.

A Tropical Cyclone Wind Signal level of number one (TCWS #1) has been issued over Sorsogon, Ticao Island, Catanduanes and the southern portion of Albay, Northern Samar, the northern portion of Samar and Mindanao, the second-largest in the country.

A TCWS #1 means a tropical cyclone will affect the locality and winds of 30 to 60 kilometers per hour may be expected in at least 36 hours or intermittent rains may be expected within 36 hours, PAGASA explains.

The country's Department of Science and Technology Philippine Institute of Volcanology and Seismology (DOST-PHIVOLCS) also "warns of potential lahars and sediment-laden streamflows on all river channels draining the slopes of Mayon Volcano, particularly the Miisi, Binaan, Anoling, Quirangay, Maninila, Masarawag, Muladbucad, Nasisi, Mabinit, Matan-ag, and Basud Channels, that may be generated by heavy rainfall brought about by Tropical Storm 'AMBO'."

"DOST-PHIVOLCS strongly recommends increased vigilance and readiness of communities in pre-determined zones of lahar hazards in Mayon Volcano. Prolonged and heavy rainfall may generate post-eruption lahars on major channels draining the Mayon Volcano edifice by incorporating loose material from thick pyroclastic density current (PDC) deposits and remnant ashfall from the January-March 2018 eruption," it adds.

The Mayon Volcano is the most active volcano in the country and last erupted in January 2018 before its volcanic activity declined by the end of March 2018.

Tropical cyclones are the most powerful weather events on the planet, NASA notes.

"On May 12, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite provided a visible image of Vongfong that showed the storm had a more rounded shape than it did the previous day, as it continued to consolidate.

Thunderstorm Advisory No. 5 #NCR_PRSD
Issued at: 6:25 PM,13 May 2020

— PAGASA-DOST (@dost_pagasa) May 13, 2020

"A more rounded shape in a tropical cyclone indicates it is becoming a more organized storm. Infrared satellite imagery also indicated cooling cloud top temperatures, which means that cloud tops are extending higher into the troposphere. The higher the cloud top, the stronger the uplift of air in a storm, and usually, the stronger the storm," it adds.

Last December, more than 300,000 residents in Luzon were evacuated after a powerful typhoon (Typhoon Kammuri) hit the region.

The Philippines, home to nearly 100 million people, went into lockdown following the outbreak of the novel coronavirus. The country has seen at least 11,350 confirmed cases, as of Wednesday, according to the latest figures from Johns Hopkins University.

The lockdown in Manila has been extended to June, Philippines President Rodrigo Duterte on Tuesday. Restrictions will be eased in parts of the country that are deemed lower-risk areas, while essential financial activities will be permitted in the capital.

Last month, Duterte warned that anyone defying lockdown measures may be shot by the military or the police.

Manila, Philippines, monsoon, flooding, rain
A commuter holding his shoes rides on a tricyle through a flooded street, caused by a heavy downpour brought on by the southwest moonson in Manila in the Philippines on August 2, 2019. Getty Images