The Marikina City local government placed the Marikina River on first alarm on Saturday, August 29, 2026, as continuous downpours enhanced by the Southwest Monsoon (Habagat) caused water levels to swell steadily past the initial warning threshold.
According to updates released by the Marikina City Public Information Office (PIO), river sensors recorded a water elevation of 15.0 meters at 12:17 p.m., prompting the activation of the first alarm. The water level climbed further to 15.2 meters just twenty minutes later at 12:37 p.m.
The first alarm serves as an alert for low-lying and riverbank communities to monitor advisories closely and prepare emergency supplies for potential evacuation.
The surge in water levels follows torrential rains across the National Capital Region. PAGASA placed Metro Manila under Red Rainfall Warning earlier in the morning at 11:00 a.m.
Under a red rainfall advisory, severe torrential rains are anticipated, carrying a high threat of serious flooding in low-lying, riverside and urban flood-prone sections. Local emergency response units and disaster management personnel remain on high alert to assist residents should the water level trigger higher alarm stages.