Luis Weakens to LPA as Another Forms; Southwest Monsoon Also Causes Rain

Tropical Depression Luis weakened into a low pressure area (LPA) as of 8 pm on Monday, August 3, in the vicinity of Peñablanca, Cagayan. By 3 am on Tuesday, August 4, the LPA that was formerly Luis was located near Baggao, Cagayan. Luis had made landfall in Maconacon, Isabela, at 5:30 pm on Monday, bringing torrential rain and strong winds. Signal No. 1 was completely lifted at 11 pm that night, following its downgrade. Luis was the 12th tropical cyclone to enter the Philippine Area of Responsibility (PAR) in 2026 and the first for August. The now-LPA may eventually be absorbed into the circulation of Tropical Cyclone Dolphin, which is currently outside PAR. Dolphin would be given the local name Maymay if it enters PAR. Another LPA also formed inside PAR on Monday evening. By 3 am on Tuesday, it was located over the coastal waters of Balaoan, La Union. According to PAGASA Weather Specialist Veronica Torres, the LPA that was formerly Luis is unlikely to redevelop into a tropical cyclone. The second LPA is also unlikely to become a tropical cyclone within 24 hours. However, these two LPAs are causing significant rain in Central and Northern Luzon on Tuesday. Heavy to intense rainfall (100-200 millimeters) is expected in Zambales and Bataan. Moderate to heavy rain (50-100 mm) is forecast for Benguet, Ilocos Sur, La Union, Pangasinan, Ifugao, Mountain Province, Tarlac, Nueva Vizcaya, Nueva Ecija, and Pampanga. Scattered rain and thunderstorms may also occur in other areas not mentioned in Central Luzon, the Ilocos Region, the Cordillera Administrative Region, and Cagayan Valley. Floods and landslides are still possible due to the LPAs. Meanwhile, the southwest monsoon, or habagat, is affecting Metro Manila, Calabarzon, much of Mimaropa, and portions of Western Visayas on Tuesday. PAGASA's latest rainfall advisory indicates that the areas most affected by the southwest monsoon over the next three days are: Tuesday, August 4: Metro Manila, Bulacan, Cavite, Batangas, Occidental Mindoro (moderate to heavy rain, 50-100 mm). Wednesday, August 5: Ilocos Norte, Ilocos Sur, Pangasinan, La Union, Zambales, Bataan, Tarlac, Benguet, Nueva Ecija, Pampanga, Batangas, Occidental Mindoro (moderate to heavy rain, 50-100 mm). Thursday, August 6: Ilocos Sur, La Union, Pangasinan, Benguet, Zambales, Bataan, Batangas, Occidental Mindoro, Antique (moderate to heavy rain, 50-100 mm). The weather bureau warned that rain due to the southwest monsoon may also trigger floods and landslides. PAGASA continues to monitor Typhoon Dolphin, located 2,330 kilometers east northeast of extreme Northern Luzon at 3 am on Tuesday, moving west at 25 km/h. Dolphin has maximum sustained winds of 150 km/h and gustiness of up to 185 km/h, having been a super typhoon at its peak. Dolphin might enter PAR but is expected to stay near the northern boundary, according to Torres. However, the typhoon is seen to enhance the southwest monsoon.