Wednesday, September 9, 2026 — Two overlapping weather systems are combining to bring significant rainfall across the Philippines today, with Northern Luzon bearing the heaviest impact, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). The agency's 4:00 AM bulletin warns of heavy to very heavy rain, possible flash floods, and landslide risk in several parts of Luzon, while the rest of the country contends with unsettled skies and scattered showers.
What Is Driving Today's Weather?
Two distinct systems are at work today. The first is the Southwest Monsoon, locally called habagat — a seasonal wind pattern that draws warm, moisture-laden air from the South China Sea into the country every June through September, producing widespread cloudiness and rain, particularly on the western side of the archipelago. Today, habagat is directly influencing Central Luzon, Southern Luzon, and the Visayas.
The second system is the trough of Tropical Depression "KROVANH." A trough is the outer arm of a tropical cyclone's circulation — a line of low pressure that extends outward from the storm's center and funnels clouds and heavy rainfall into areas even far from the cyclone's eye. KROVANH's trough is currently sweeping across Northern Luzon, amplifying the already wet monsoon conditions in that part of the country.
Together, these two systems are producing a broad zone of heavy rain stretching from the northernmost tip of Luzon down to the Visayas, with Mindanao also under the influence of unsettled weather from scattered atmospheric disturbances.
Region-by-Region Forecast
Northern Luzon — Heavy Rain, Flash Flood and Landslide Risk
Residents of the Ilocos Region, Cagayan Valley, and the Cordillera Administrative Region (CAR) face the most serious weather today. PAGASA is forecasting heavy to very heavy rain with scattered thunderstorms in these areas, driven by the trough of Tropical Depression KROVANH. The agency specifically flags the risk of flash floods and — critically for the mountainous terrain of CAR and parts of Cagayan — landslides. Anyone living near riverbanks, steep slopes, or low-lying flood-prone zones in these provinces should be on heightened alert throughout the day and overnight.
Metro Manila and the Rest of Luzon — Cloudy With Scattered Thunderstorms
Metro Manila, along with Batangas, Cavite, Laguna, Quezon, Rizal, Palawan, and other provinces across Luzon not directly in the path of KROVANH's trough will experience cloudy skies with scattered rain and thunderstorms, produced by the Southwest Monsoon. While conditions here are less extreme than in Northern Luzon, PAGASA notes that flash flooding remains possible — particularly in low-lying urban areas, drainage-prone barangays, and coastal zones. Expect on-and-off rain rather than continuous downpours, but do not let brief dry spells create a false sense of security.
Visayas — Partly Cloudy to Cloudy With Thunderstorms
The Visayas — including Eastern Visayas, Western Visayas, and Central Visayas — will see partly cloudy to cloudy skies with scattered rain and thunderstorms, also courtesy of the Southwest Monsoon. Flash floods and local flooding are possible during intense rain bursts. While the overall outlook is somewhat less severe than Luzon, residents in areas with poor drainage or near rivers should remain vigilant, particularly during the afternoon and evening hours when thunderstorm activity typically intensifies.
Mindanao — Isolated to Scattered Showers and Thunderstorms
Mindanao will experience partly cloudy to cloudy skies with isolated to scattered rain and thunderstorms, attributed to scattered atmospheric disturbances. Localized flooding during heavy downpours remains possible. Conditions are comparatively more manageable than in Luzon, but Mindanao residents — especially those in low-lying and riverine communities — should not dismiss the threat of sudden, intense rain bursts.
Decoding the Warnings: What Does This Mean?
PAGASA's bulletin specifically identifies hazards tied to today's weather systems: possible flash floods across Luzon, the Visayas, and Mindanao, and landslide risk in Northern Luzon and the Cordillera. Flash floods can occur with little to no warning, even in areas that are not currently raining, if heavy rain falls upstream. Landslides in mountainous terrain can be triggered by sustained or intense rainfall saturating the soil.
If you are unsure how to interpret PAGASA's warning levels — including rainfall color-coded alerts and tropical cyclone wind signals — read our guide on how to read PAGASA's weather warnings for a plain-language breakdown of what each level means and what action to take.
In practical terms today: if you live in a flood-prone area of Northern Luzon, the Cagayan Valley, or CAR, treat this as a day to stay informed and be ready to move to higher ground or an evacuation center at short notice if local authorities issue evacuation orders.
Wind and Coastal Water Conditions
Winds across the country are light to moderate, according to PAGASA's forecast. Northern Luzon will see northeasterly winds; the Visayas and the rest of Luzon will experience southwesterly winds; and Mindanao will see southeasterly to southwesterly winds. Coastal waters are slight to moderate in wave height nationwide — which means the sea is manageable for larger vessels but choppy enough to pose risk for small and motorized bancas.
What It Means for You
Commuters (Metro Manila and Luzon)
Expect rain-slicked roads, reduced visibility during thunderstorms, and possible flooding in low-lying underpasses and streets. Allow extra travel time, especially in the afternoon when convective thunderstorms tend to peak. Keep an eye on local government social media pages for flood alerts in your barangay.
Fisherfolk and Small-Boat Operators
Coastal waters are rated slight to moderate nationwide — not outright dangerous for all vessels, but PAGASA urges caution. Small and motorized bancas are most vulnerable to sudden squalls, which frequently accompany the thunderstorm activity forecast today. If you are in Northern Luzon coastal areas where KROVANH's trough is active, conditions may deteriorate quickly. Do not venture far from shore today.
Farmers
The heavy rain forecast for Northern Luzon and the Cordillera region carries significant risk for crops. Flash flooding can inundate low-lying farm fields rapidly. Farmers in these areas should secure movable equipment and livestock and avoid working on steep or terraced farm slopes where landslide risk is elevated today.
Students and Parents
Class suspensions are decided by local government units, not PAGASA. However, the heavy rain and flash flood risk in Northern Luzon, CAR, and Cagayan Valley warrants close monitoring. Parents in these areas should check their local LGU announcements early this morning before sending children to school. Have an emergency contact plan in place.
Outdoor Workers and Construction Personnel
Workers at outdoor construction sites, road projects, and quarrying operations in Luzon — particularly Northern Luzon — face elevated risk today from heavy rain, reduced visibility, and potential landslides near slopes and elevated terrain. Site supervisors should assess whether it is safe to continue operations and have a clear evacuation protocol ready.
Temperature Outlook
PAGASA recorded temperature data at its weather station in Science Garden, Diliman, Quezon City for the 24-hour period ending 8:00 PM on September 8, 2026. The maximum temperature was 26.1°C, recorded at 2:00 PM, while the minimum was 24.6°C, recorded at 5:00 AM. Relative humidity ranged from a maximum of 87% at 6:00 AM to a minimum of 64% at 2:00 PM. The wet, humid conditions are consistent with active monsoon weather — expect the air to feel sticky and muggy throughout the day even during brief dry spells.
Tides and Astronomical Data (Metro Manila)
For Metro Manila, today's high tide is at 7:50 AM at 4.33 meters, and a low tide of -0.45 meters at 4:26 PM. Sunrise is at 5:48 AM and sunset at 6:02 PM. Moonrise is at 8:34 AM and moonset at 8:05 PM. Coastal communities along Manila Bay and other low-lying coastal areas should note the relatively high morning tide in combination with today's rain — combined surge and runoff can worsen urban flooding in these zones.
Bottom line: Northern Luzon faces the most serious weather today — heavy rain, flash flood risk, and landslides are all on the table thanks to Tropical Depression KROVANH's trough and the Southwest Monsoon working together. If you are in Ilocos, Cagayan Valley, or the Cordillera, stay close to reliable weather updates and be ready to act on any evacuation orders from your local government. Everyone else across Luzon, the Visayas, and Mindanao should expect rain and thunderstorms throughout the day and keep an umbrella — and a flood awareness plan — close at hand.
Monitor official PAGASA updates at pagasa.dost.gov.ph.