Philippines: Typhoon Rai tracking westwards across the Sulu Sea early Dec. 17. Landfall likely in Palawan Province Dec. 17 /update 7

Event

Typhoon Rai (known locally in the Philippines as Odette) was tracking westward across the Sulu Sea early Dec. 17 after making its first landfall in Surigao del Norte Province the afternoon of Dec. 16. The storm made additional landfalls over Dinagat Islands, Southern Leyte, Bohol, and Cebu provinces Dec. 16. As of 08:00 PHT, the storm's center of circulation was approximately 511 km (318 miles) south of Manila. Forecast models indicate the system will slightly strengthen over the coming hours as it tracks westward and makes another landfall over Palawan Province Dec. 17. The system will maintain typhoon strength as it subsequently enters the South China Sea late Dec. 17. Rai will likely weaken as it gradually turns northwestward then northwards, making a close approach to Central Vietnam early Dec. 19-20 and the Paracel Islands early Dec. 20. The storm is likely to weaken rapidly into a tropical storm as it turns to track northeast, passing east of Hainan Province, China, early Dec. 21 before weakening into a tropical depression as it turns to track eastwards. Some uncertainty remains in the track and intensity forecast, and changes could occur over the next few days.

Authorities maintain evacuation orders for at least 332,000 people across Caraga, Central Visayas, Eastern Visayas, Northern Mindanao, Western Visayas, and Zamboanga Peninsula regions. Officials evacuated most of them ahead of the storm. Hundreds of schools and offices have been temporarily closed in these regions. Further evacuations are likely across the central Philippines in the coming hours and days as Typhoon Rai impacts the region.

As of early Dec. 17, all of Biliran, Bohol, Camiguin, and Surigao del Norte provinces as well as much of Agusan del Norte, Agusan del Sur, Antique, Capiz, Cebu, Davao Oriental, Eastern Samar, Iloilo, Lanao del Norte, Leyte, Misamis Occidental, Misamis Oriental, Negros Oriental, Southern Leyte, and Surigao del Sur provinces are without power. At least one person has died in Iloilo City due to a collapsed house and two others have died in Northern Mindanao. The true extent of the storm's impact is likely to become more clear in the coming days once it has passed and authorities are able to conduct damage assessments.

Government Advisories
As of early Dec. 17, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) had issued the following warnings:

• Tropical Cyclone Wind Signal (TCWS) 3: Southern Antique, southern Iloilo, and northern Palawan (including Cagayancillo

• and Cuyo Islands) provinces.

• TCWS 2: Aklan, the rest of Antique, Capiz, the rest of Iloilo, Guimaras, Negros Occidental, northern and central Negros Oriental, southern Occidental Mindoro, southern Oriental Mindoro, central Palawan (including Kalayaan and Calamian Islands), and western Romblon provinces.

• TCWS 1: Batangas, Biliran, Bohol, Cebu (including Bantayan and Camotes Islands), western Leyte, Marinduque, Masbate (including Ticao and Burias Islands), northern Misamis Occidental, the rest of Occidental Mindoro (including Lubang Islands), the rest of Oriental Mindoro, the rest of Palawan, the rest of Romblon, Siquijor, western Southern Leyte, and northern Zamboanga del Norte provinces.

Authorities have warned of heavy-to-torrential rainfall over the Western Visayas region as well as Palawan (including Calamian, Cuyo, and Cagayancillo Islands) and Negros Oriental provinces Dec. 17, while moderate-to-heavy rainfall is likely across the Bicol Region, the rest of Mimaropa, and Zamboanga Peninsula regions as well as Quezon Province Dec. 17. There is a moderate-to-high risk of storm surge of up to 3 meters (10 feet) which may cause flooding in low-lying coastal areas in Antique, Guimaras, Iloilo, Negros Occidental, Negros Oriental, and northern Palawan (including Calamian, Cuyo, and Cagayancillo Islands) provinces.

Authorities will probably issue new warnings or update existing advisories throughout the system's progression in the coming days. Weather warnings could remain active even after the system's immediate threat has diminished, as some areas may still be highly susceptible to rain-induced hazards. Officials may announce additional evacuations if weather conditions prove particularly hazardous.

Hazardous Conditions
Typhoon Rai will likely continue to bring heavy rainfall, strong winds, and rough seas to most of the Visayas, southern Luzon, and northern Mindanao regions of the Philippines in the coming days. Sustained heavy rainfall could trigger flooding in low-lying communities near streams, creeks, and rivers, as well as in urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of large reservoirs could experience flash flooding after relatively short periods of intense rainfall. Rain-induced landslides are possible in steeply sloped terrains. Flooding could isolate some communities for several days. Prolonged sea swells and storm surge generated by the system could result in coastal flooding. Persistent onshore flow could make it difficult for the surge to recede and for water levels to decrease in coastal river catchments.

In addition to forecast heavy rain, flooding, and storm surge, the storm could produce damaging wind gusts. Widespread and prolonged power outages due to uprooted trees and toppled utility lines are possible.

Transport
Inclement weather associated with the storm could trigger localized business, transport, and utility disruptions. Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Areal flooding in urban locations could also result in severe traffic congestion, while strong winds will pose a hazard to high-profile vehicles. Heavy rain and low visibility may trigger flight disruptions at regional airports. Tugdan Airport (TBH) in Romblon Province was closed Dec. 15. At least 73 seaports are also closed. The Manila International Airport Authority (MIAA) reported that as of early Dec. 17, almost 100 domestic flights had been canceled, with hundreds more expected to be affected nationwide. Authorities closed the Mactan-Cebu International Airport (CEB) late Dec. 16 due to damage caused by the typhoon; all flights are canceled until further notice.

Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after weather conditions have improved. If there is severe damage to infrastructure, repair or reconstruction efforts may exacerbate residual disruptions.

Advice

Activate contingency plans in areas where officials forecast tropical storm or typhoon conditions. Heed all evacuation orders. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the high potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents and any necessary medications in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks.

Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.

Resources

Joint Typhoon Warning Center
Philippine Atmospheric, Geophysical and Astronomical Services Administration