Southwest monsoon brings heavy rain to fewer areas, but floods still likely

MANILA, Philippines – Fewer areas could have significant rainfall from the southwest monsoon or habagat in the coming hours and days, but the weather bureau advised Luzon to remain on alert as the soil in many regions may already be saturated, making floods still likely.

The Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) said in a briefing at 5 pm on Monday, August 10, that the southwest monsoon is still affecting nearly the entire Luzon as well as Western Visayas, but some areas are already seeing gradually improving weather.

For the next 24 hours, moderate to intense rain may persist in more than a dozen areas, with Zambales, Bataan, and Occidental Mindoro possibly worst-hit. Beyond that period, the rain is expected to ease further, becoming moderate to heavy in just a handful of provinces.

Check PAGASA’s latest rainfall outlook below.

Monday afternoon, August 10, to Tuesday afternoon, August 11

• Heavy to intense rain (100-200 millimeters): Zambales, Bataan, Occidental Mindoro
• Moderate to heavy rain (50-100 mm): Metro Manila, Ilocos Sur, La Union, Pangasinan, Benguet, Tarlac, Pampanga, Bulacan, Rizal, Cavite, Batangas

Tuesday afternoon, August 11, to Wednesday afternoon, August 12

• Moderate to heavy rain (50-100 mm): La Union, Benguet, Pangasinan, Zambales, Bataan, Occidental Mindoro

Wednesday afternoon, August 12, to Thursday afternoon, August 13

• Moderate to heavy rain (50-100 mm): Zambales, Bataan, Occidental Mindoro

For Monday evening, other areas in Luzon not mentioned above, along with Western Visayas, may have scattered rain and thunderstorms due to the southwest monsoon.

Monday’s downpours resulted in Quezon City’s La Mesa Dam breaching its spilling level of 80.15 meters. PAGASA recorded a level of 80.17 meters at 5 pm, while the Barangay North Fairview Disaster Risk Reduction and Management Committee reported 80.24 meters as of 7 pm.

Whenever the La Mesa Dam overflows, communities in Quezon City, Caloocan City, Malabon City, Navotas City, and Valenzuela City, especially those near the Tullahan River, are at risk of flooding.

Many areas in Luzon have already been hit by floods and landslides in recent days.

The National Disaster Risk Reduction and Management Council reported on Monday morning that the southwest monsoon, Tropical Depression Luis, and Tropical Storm Maymay (Kujira) combined have left at least eight people dead, nine others injured, and one missing.

Meanwhile, PAGASA continues to monitor a tropical cyclone outside the Philippine Area of Responsibility (PAR) — a tropical storm with the international name Peilou.

Peilou was last spotted 3,000 kilometers east of extreme Northern Luzon at 3 pm on Monday, moving east or away from PAR at a fast 35 kilometers per hour (km/h).

The tropical storm has maximum sustained winds of 75 km/h and gustiness of up to 90 km/h.

PAGASA said Peilou is not expected to enter PAR.

The weather bureau earlier predicted that two to four tropical cyclones could develop within or enter PAR in August. Luis and Maymay are this month’s tropical cyclones, so far. – Rappler.com