28 December 2014
Tropical storm Seniang (international name, Jangmi) was the 19th and last storm to hit the Philippines in 2014. Seniang first manifested as a low-pressure area (LPA) and entered the Philippine Area of Responsibility (PAR) on December 26, 2014. It then formed into a tropical depression and was named Seniang on December 28, 2014 initially packing winds at 45 kph and moving in a northwest direction as it approached Surigao Del Sur where it was initially expected to make landfall in the city of Tandag. The national weather agency, PAGASA, also forecasted the typhoon to carry moderate to heavy rainfall (7-15 millimeters per hour) within its 300 km diameter. It made landfall at around 3:45 AM in Brgy. Bakulin, Hinatuan, Surigao Del Sur on December 29 with maximum sustained winds of 65 kph, raising public storm warning signals 1 and 2 in some areas in Visayas and Mindanao. It also made landfall in Cebu, Bohol, and Negros Oriental before it was downgraded to an LPA the day before New Year’s. Seniang eventually left PAR on January 2,2014.The NDRRMC reported 66deaths as of 9 January 2015, with forty-three missing and six injured. A total of 124,305 families were affected and more than PhP800 million were lost in damages to crops and infrastructure (NDRRMC, 2015).
Seniang delivered intense to torrential rains over a prolonged period and caused widespread floods and landslides in Northern Mindanao and the Visayas. Although Seniang was weaker in terms of wind speed compared to Sendong, it delivered as much rain as Sendong. The amount of rainfall during Sendong was in the order of 180 mm over the span of 24 hours (Manila Observatory, 2011) while Project NOAH sensors recorded 100-250 mm of rainfall in the span of one day in Agusan, Surigao Del Sur, Misamis Oriental, Cebu, Bohol, and Western Samar among others. Sensors in Tagoloan River in Misamis Oriental registered a water level of up to eight meters. The swelling of the river generated floods that could have turned out into a disaster. However, the timely delivery of information to these communities, relayed through social media and direct calls to DRMM officers, may have helped avert a possible catastrophe. In Tagoloan, with a population of 63,850, an alert of incoming floods was communicated in the morning of December 29,2014. By the time floods rushed in the afternoon at 3:10 PM, people were already out of harm’s way, except for one person who drowned. By 4:00 PM, Misamis Oriental Governor Yevgeny Vincente Emano declared Misasmis Oriental under a state of calamity (Manlupig, 2014). The flood hazard in Tagoloan was there, but no disaster in terms of mass casualties happened.
In previous typhoon events, the DOST Project NOAH used Facebook and Twitter to spread information about the availability of storm surge, flood, and landslide hazard maps to help communities locate safer ground. This was applied as a strategy for communicating warnings and information on Seniang in the morning of December 28, soon after PAGASA announced that the LPA was officially categorized as a tropical depression. Twitter, in particular, proved to be valuable in disseminating critical information on intense to torrential rainfall warnings both to the general public and especially to local partners in the affected communities, such as Compostela Valley, Cagayan de Oro, Butuan City, and Misamis Oriental. DOST-Project NOAH closely monitored on-ground events via short message service (SMS), directly communicating with local disaster officials in affected LGUs. Local contacts were advised to ensure evacuation and were duly reminded to use the hazard maps available in the NOAH website. The partners, in turn, reported that indeed they were using the said tools and emphasized how helpful these had been for them. Because of Facebook and Twitter, key messages and PAGASA advisories were crafted for general readership and comprehension. Hashtags were utilized to tag affected provinces, and weather advisories were translated to Bisaya, Ilonggo, and Hiligaynon to target the affected communities. This underscores the need to keep information on weather disturbances and hazard advisories simple and target-specific.
France-Presse, A. (2014). ‘Seniang’ death toll rises to 11. Philippine Daily Inquirer.
Manila Observatory. (2011). Preliminary Analysis on Extreme Weather Event: Tropical Storm Sendong.
Manlupig, K. (2014). Misamis Oriental declares state of calamity over Seniang. Rappler.
NDRRMC. (2015). Sit. Rep. No. 22 Effects of Tropical Storm “Seniang”.