Philippines: Adverse weather forecast across the southern and central regions through at least Dec. 30

Event

A low-pressure system is forecast to bring showers and thunderstorms across southern and central Philippines through at least Dec. 30. As of Dec. 27, the Philippine Atmospheric, Geophysical, and Astronomical Administration (PAGASA) has issued a weather advisory warning of moderate to heavy rains over the Eastern Visayas Region. Light to moderate rain is likely over the Caraga and Zamboanga Peninsula regions as well as Bohol, Palawan, and Northern Mindanao provinces. The heavy downpours could trigger flooding and landslides in parts of the affected areas. Further isolated showers and storms are forecast across the rest of the country Dec. 30.

As of Dec. 27, PAGASA has issued the following flood advisories across the Philippines:

• Severe general flood advisories (the second lowest level on a four-tier scale): Caraga, Eastern Visayas, Northern Mindanao, Mimaropa, and Zamboanga Peninsula regions.

• Moderate general flood advisories: most of the rest of central and southern Philippines.

Officials could update and possibly extend the coverage of weather alerts over the coming days.

Heavy rainfall since Dec. 25 resulted in flash flooding that killed 13 people. At least 23 people remain missing; search and rescue operations are ongoing. Authorities preemptively evacuated 136 people from the Eastern Visayas and Zamboanga Peninsula regions. As of Dec. 27, more than 45,000 people remain displaced across Bangsamoro Autonomous Region in Muslim Mindanao, Bicol, Eastern Visayas, Northern Mindanao, Mimaropa, and Zamboanga Peninsula regions. At least 165 structures have been destroyed and another 369 other structures have been damaged.

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. 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)