QUEZON CITY, October 31, 2026 — Millions of Filipinos across the country face a wet and hazardous Saturday as a Low Pressure Area, a shear line, and the northeast monsoon combine to bring widespread rains and thunderstorms from Luzon to Mindanao, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) warned in its 4:00 AM forecast issued today.
The forecast is valid until 4:00 AM on Sunday, November 1, 2026. Flash floods and landslides are possible in multiple regions, and residents in affected areas are urged to stay alert and avoid flood-prone zones.
What Is Driving Today's Weather
Three separate weather systems are responsible for today's conditions across the archipelago.
The primary driver across the central and southern Philippines is a Low Pressure Area (LPA), which PAGASA estimated at 3:00 AM today to be located approximately 320 kilometers east of Borongan City, Eastern Samar, at coordinates 11.7°N, 128.4°E. An LPA is a region of the atmosphere where air pressure is lower than its surroundings, causing warm, moist air to rise and condense into clouds and rain. Because it sits close to the eastern coast of the Visayas, it is pulling moisture-laden air over a broad swath of the central and southern Philippines, producing the persistent cloudy skies, scattered rains, and thunderstorms that residents from Bicol to Mindanao will experience today.
In the northern and central parts of Luzon, a shear line is the culprit. A shear line is a boundary in the atmosphere where winds blowing from different directions meet, forcing air upward and generating clouds, rain, and thunderstorms along its length. Today it is affecting the eastern portions of Northern and Central Luzon, including Cagayan, Isabela, Aurora, and Quezon provinces.
Meanwhile, the northeast monsoon — known locally as the amihan — is the dominant force over the northern sections of Luzon. The amihan is a seasonal wind system that blows from the northeast and typically brings cooler, drier air to northern Luzon, though it can still produce light rains over exposed coasts and elevated terrain. Today it is keeping conditions partly cloudy to cloudy with isolated light rains over the Ilocos Region, the Cordillera Administrative Region, and the rest of Cagayan Valley.
Finally, Metro Manila and other parts of Luzon not directly under the shear line or amihan will see isolated rainshowers or thunderstorms triggered by localized weather systems — meaning heat, humidity, and atmospheric instability building up locally rather than from a large weather system overhead.
Region-by-Region Forecast
Northern and Central Luzon — Shear Line and Amihan
Residents of Cagayan, Isabela, Aurora, and Quezon provinces should prepare for cloudy skies with scattered rains and isolated thunderstorms throughout the day, courtesy of the active shear line. PAGASA warns that these rains could be moderate to at times heavy, raising the risk of flash floods and landslides, particularly in low-lying areas near rivers and communities situated on or near slopes.
Those in the Ilocos Region, the Cordillera Administrative Region, and the rest of Cagayan Valley — areas under the northeast monsoon — can expect partly cloudy to cloudy skies with only isolated light rains. No significant impacts are forecast for these areas, though the Cordillera's mountainous terrain means even light rains can contribute to slippery roads at higher elevations.
Metro Manila and the Rest of Luzon
Metro Manila and other parts of Luzon not specifically named above will experience partly cloudy to cloudy skies with isolated rainshowers or thunderstorms driven by localized weather disturbances. PAGASA flags the risk of flash floods and landslides during severe thunderstorms, reminding residents not to be lulled into complacency by stretches of dry weather during the day — strong, localized downpours can develop quickly.
Visayas and Bicol Region and MIMAROPA
The entire Visayas, together with the Bicol Region and MIMAROPA (Mindoro, Marinduque, Romblon, Palawan), will bear the brunt of the LPA's influence today. These areas should expect cloudy skies with scattered rains and thunderstorms throughout the forecast period. PAGASA explicitly warns of possible flash floods and landslides due to moderate to heavy rains. Communities near rivers, coastal flood zones, and hilly or mountainous areas should be on heightened alert.
Mindanao
The LPA is also spreading its effects southward, giving Mindanao cloudy skies with scattered rains and thunderstorms. As with the Visayas, PAGASA flags the risk of flash floods and landslides from moderate to heavy rainfall. Residents of low-lying municipalities and those near riverbanks across all of Mindanao's regions should monitor water levels and heed any local government advisories.
Decoding the Warnings: What the Hazard Flags Mean for You
PAGASA's forecast today does not raise any tropical cyclone wind signals — Typhoon In-fa (2631), while a powerful storm with maximum sustained winds of 165 km/h near its center and gusts of up to 205 km/h, remains 2,245 kilometers east of extreme northern Luzon and is outside the Philippine Area of Responsibility (PAR). It is moving northwestward at 25 km/h. PAGASA will continue monitoring it, but as of this bulletin it poses no direct threat to any part of the country.
The active hazards today are the flash flood and landslide warnings tied to the LPA and the shear line. These are not formal color-coded rainfall warnings but are PAGASA's stated impact forecasts — a signal that rainfall in the affected areas could be intense enough, particularly during thunderstorm episodes, to overwhelm drainage systems and destabilize slopes. If you live in a flood-prone barangay or near a hillside in Visayas, Mindanao, Bicol, MIMAROPA, or in the shear line's path across Cagayan, Isabela, Aurora, and Quezon, you should know what to do if conditions worsen. For a full guide on reading PAGASA's hazard and warning systems, see how to read PAGASA's weather warnings.
Wind and Sea Conditions
Winds across Luzon and Visayas today will be light to moderate, blowing from the northeast to east. Coastal waters in these areas will range from slight to moderate, with wave heights of 0.6 to 2.5 meters.
Over Mindanao, winds will also be light to moderate but blowing from the southwest to southeast. Coastal waters there will be slight to moderate, with wave heights of 0.6 to 1.8 meters.
While these are not the roughest sea conditions, the combination of rain, reduced visibility during thunderstorms, and waves reaching up to 2.5 meters in some areas of Luzon and Visayas means maritime conditions today demand caution.
What It Means for You
Commuters
Metro Manila commuters and those in provinces under scattered rains and thunderstorms should expect possible flooding along low-lying streets and underpasses during heavy rain episodes. Allow extra travel time, avoid flooded roads, and keep an eye on PAGASA and local government social media channels throughout the day. Severe thunderstorms can develop quickly, so if you are caught outside, seek sturdy shelter immediately.
Fisherfolk and Small-Boat Operators
While no gale warning has been issued, wave heights of up to 2.5 meters across Luzon and Visayas coastal waters are significant for small bancas and fishing boats. Operators in the Visayas, Bicol, MIMAROPA, and along Luzon's eastern coast should exercise caution and consider whether conditions are safe before heading out. Mindanao's coastal waters are somewhat calmer at up to 1.8 meters, but thunderstorms can rapidly deteriorate conditions at sea. Always check with the Philippine Coast Guard and the nearest PAGASA station before departure.
Farmers
Farmers in Cagayan, Isabela, Aurora, and Quezon, as well as those in the Visayas and Mindanao, should secure crops and farm equipment ahead of potentially heavy rains and thunderstorms. Flash flooding in low-lying agricultural areas could damage crops and irrigation infrastructure. Avoid working in open fields during thunderstorm activity.
Students, Parents, and Schools
With the day falling on a Saturday and Halloween, families planning outdoor activities should monitor conditions closely throughout the morning and afternoon. Afternoon thunderstorms are possible in Metro Manila and many other areas. Local government units in Visayas, Mindanao, and parts of Luzon may issue advisories if conditions worsen — follow official channels rather than social media rumors.
Outdoor Workers
Construction workers, delivery riders, utility crews, and others working outdoors in areas under scattered rains and thunderstorm warnings should ensure they have safe shelter options and that supervisors are tracking weather updates in real time. Lightning from isolated thunderstorms is a serious hazard in open areas. Stop outdoor work and move to shelter if thunder is heard.
Temperature and Humidity Outlook
PAGASA's weather station at Science Garden in Diliman, Quezon City recorded temperature and humidity data for the 24-hour period ending at 8:00 PM yesterday, October 30, 2026. The maximum temperature reached 30.8°C at 2:00 PM, while the minimum dropped to 25.3°C at 6:00 AM. Relative humidity peaked at 89% at 6:00 AM and dipped to a minimum of 66% at 2:00 PM. These figures are specific to the Science Garden station in Quezon City and are representative of Metro Manila conditions.
Today's widespread cloud cover and rain across many regions may keep temperatures from rising as high in affected areas, though humidity is expected to remain elevated, making conditions feel heavy and uncomfortable even when it is not actively raining.
Tidal Information for Manila Bay
For boaters and those living along Manila Bay, PAGASA — courtesy of NAMRIA — reports that high tide over Manila Bay occurred at 12:10 AM today at 1.28 meters, and low tide is at 9:17 AM at -0.26 meters. Sunrise today is at 5:51 AM and sunset at 5:28 PM. The moon rises at 10:26 PM and sets at 10:53 AM, with lunar illumination at 65%.
Bottom Line
If you are in the Visayas, Mindanao, Bicol Region, MIMAROPA, or in Cagayan, Isabela, Aurora, or Quezon province, treat today's forecast seriously: PAGASA warns of possible flash floods and landslides, and you should know your evacuation route and stay away from rivers, slopes, and flood-prone areas. Everywhere else in the Philippines, stay alert for sudden, localized thunderstorms that can bring brief but intense flooding — and keep your plans flexible this Halloween Saturday.
Monitor official PAGASA updates at pagasa.dost.gov.ph.