Philippines: Adverse weather forecast across most of the country through at least Nov. 22 /update 1

Event

A combination of weather systems are forecast to bring adverse weather conditions to most of the Philippines through at least Nov. 22. As of Nov. 18, the Philippine Atmospheric, Geophysical, and Astronomical Administration (PAGASA) has issued a weather advisory due to the combined effects of the Intertropical Convergence Zone (ITCZ) and low-pressure area; moderate to heavy rainfall over the Central and Eastern Visayas, Caraga, Davao, and Soccsksargen regions is forecast. Light to moderate rainfall is likely across the rest of Mindanao as well as the Bicol and Western Visayas regions and Palawan Province. The heavy downpours could trigger flooding and landslides in parts of the affected areas. As of Nov. 18, PAGASA has issued orange severe general flood advisories (the second lowest level on a four-tier scale) for portions of Caraga, Davao, Eastern Visayas, and Soccsksargen regions and yellow moderate general flood advisories for most of the remaining areas across the country. Thunderstorms and rainfall is forecast to persist through at least Nov. 22. Officials could update and possibly extend the coverage of weather alerts over the coming days.

Hazardous Conditions
Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rainfall has saturated the soil.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Transport
Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. Severe weather could also trigger flight delays and cancellations at airports in the region, including Manila Ninoy Aquino International Airport (MNL). Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.

Advice

Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.

Resources

Philippine Atmospheric, Geophysical, and Astronomical Administration (PAGASA)