Authorities on Thursday morning raised the first alarm over Marikina river as the water level reached over 15 meters due to the continuous rains experienced in Metro Manila and several provinces.

As of 7 AM, the Marikina Public Information Office (PIO) reported that the water level is now at 15.9 meters, which is above the the sea level.

The recorded rainfall count upstream showed precipitation:

• Mt. Campana: 0 mm
• Mt. Boso-Boso: 0 mm
• Mt. Aries : 4 mm
• Mt. Oro : 1 mm
• Nangka: 1 mm

Marikina PIO said all flood gates at Manggahan Floodway have been opened to divert the peak of the water to Laguna de Bay.

Under Alert Level 1, residents within the vicinity are urged to prepare for evacuation for safety.

Based on PAGASA's latest weather advisory issued at 4 AM, Metro Manila Cordillera Administrative Region (CAR), Cagayan Valley, CALABARZON, MIMAROPA, and the rest of Central Luzon will experience cloudy skies with scattered rain showers and thunderstorms due to the Southwest Monsoon or habagat that is enhanced by Typhoon Falcon.

"Possible flash floods or landslides due to moderate to at times heavy rains," the state weather bureau warned.