19 August 2013
Metro Manila and its adjacent cities experienced heavy rains on August 18 to 21, 2013. Colloquially called habagat, the extreme southwest monsoon rainfall was not brought about by a tropical storm but rather by a weather phenomenon evident in June until the end of the year. The 2013 Habagat event was reminiscent of the 2012 Habagat rains, which also hit Metro Manila in August the previous year. Habagat monsoon rains are sometimes intensified by weather events like nearby tropical cyclones such as Tropical Storm Maring (international name, Trami). The city’s DRRM officials noted that the real-time information provided by Project NOAH was very useful in the DRRM procedures, especially in enabling local authorities to make informed decisions on evacuating their constituents. Disaster officials were also able to predict the amount of water that would possibly inundate the city by looking at the amount of rainfall in the Upper Marikina river basin (formerly the Marikina Watershed Reservation). Water usually flows down from the watershed to Marikina City within two to three hours.
By 10:30 PM on August 19, local officials were able to evacuate residents from low-lying areas in the city. Earlier that day, the amount of rainfall that fell on the watershed was around 113 millimeters. According to NOAH data, 600 millimeters of accumulated rain fell on various parts of Luzon, such as Cavite, Pampanga, Bataan, Zambales, and Manila Bay in 24 hours. Southern parts of Metro Manila received more rainfall than other parts of the metro. This exceeded monsoon rains of 2012 when 472 millimeters in 24 hours, and in 2009 when Ondoy rained down 455 millimeters in 24 hours. The Marikina River swelled to 19 meters on August 20 with a rise in river water compared to its summer level equivalent to 8.84 meters. Marikina city mayor Del de Guzman claimed that the 2013 rainfall event was substantially easier to manage than the previous Habagat and Ondoy.
The Manila Times . (2013). Monday’s rainfall exceeds Ondoy, last year’s Habagat. ManilaTimes.net.
Mangunay, K. (2013). Marikina: ‘Noah’ helped save lives. Philippine Daily Inquirer.
Lagmay, A.M.F., Bagtasa, G., David, C.P., Crisologo, I., Racoma, B.A. (2014). Volcanoes magnify Metro Manila’s southwest monsoon rains and lethal floods. NOAH Open File Reports.
GMA News Online. (2013). Marikina mayor: Ondoy, 2012 Habagat still worse. GMA.
Philippine Star. (2013). Live feed: #MaringUpdates and #Habagat. philstar.com.