QUEZON CITY, June 15, 2026 — State weather forecasters are putting the entire Philippines on notice for a wet Monday, as easterly winds stir up unsettled conditions across Visayas and Mindanao while localized thunderstorm development threatens to drench Metro Manila and the rest of Luzon throughout the day.
The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) released its 24-hour public weather bulletin at 4:00 AM on June 15, 2026, effective until 4:00 AM the following day, June 16. The forecast covers the entire Philippine archipelago. PAGASA specifically cautioned residents in every region to stay alert for flash floods and landslides should any of the forecast thunderstorms intensify significantly.
Weather Systems at Play: No Tropical Cyclone, But Widespread Wet Conditions
According to PAGASA, no tropical cyclone is currently affecting the country. Instead, Monday's widespread unsettled weather is being driven by two concurrent features: easterly winds — prevailing air masses moving in from the east — affecting the eastern sections of Visayas and Mindanao, and localized thunderstorm activity generated by daytime heating and atmospheric instability, which will produce rain over Metro Manila and the rest of the country.
PAGASA's general description for virtually the entire nation is "partly cloudy to cloudy skies with isolated rainshowers or thunderstorms." While this may seem like a standard wet-season outlook, the weather bureau's explicit mention of flash flood and landslide hazards is a firm reminder that isolated thunderstorms can rapidly generate dangerous rainfall intensities over short periods — enough to overwhelm drainage systems and destabilize vulnerable hillslopes.
Luzon: Metro Manila and Provinces Bracing for Afternoon Downpours
Metro Manila and the broader Luzon landmass are forecast to experience partly cloudy to cloudy skies Monday, with isolated rainshowers and thunderstorms building up as the day progresses, PAGASA reported. The agency attributes these conditions to localized thunderstorm development — weather events triggered by daytime surface heating rather than any large-scale synoptic system.
In practical terms, morning hours may remain relatively manageable across Metro Manila and Luzon provinces, but residents and commuters should anticipate the highest probability of heavy, sudden downpours during the afternoon and early evening. Motorists navigating mountain routes in the Cordillera, Sierra Madre, and other highland areas of Luzon should exercise particular caution given the risk of landslides during intense rain.
PAGASA forecasts winds over Luzon blowing from the southeast to southwest at light to moderate speeds. Coastal waters off Luzon are expected to be slight to moderate, with wave heights ranging between 0.6 and 1.8 meters — a range that small boat and bancа operators must account for before heading out to sea.
Visayas: Eastern Provinces Under Direct Easterly Influence
Across the Visayas, weather conditions on Monday will be shaped by two overlapping factors, according to PAGASA. Eastern Visayas — comprising provinces such as Samar and Leyte — is under the more concentrated influence of the easterlies, which the weather bureau identifies as the direct cause of cloudy skies and isolated rainshowers or thunderstorms in that sub-region.
The rest of the Visayas, covering Western Visayas and Central Visayas — including Iloilo, Cebu, and Negros — will experience the broader nationwide pattern of localized thunderstorm activity. All Visayas residents, regardless of province, should remain prepared for a wet day and should monitor conditions for signs of flash flooding or landslides, particularly those living near river channels and elevated terrain.
Wind direction over the Visayas mirrors Luzon's pattern, coming from the southeast to southwest at light to moderate intensity. Coastal waters surrounding the Visayas island group are forecast to have wave heights of 0.6 to 1.8 meters, classified as slight to moderate by PAGASA.
Mindanao: Eastern Seaboard Provinces Specifically Flagged
PAGASA's Monday forecast identifies several Mindanao provinces by name as areas most directly impacted by the easterlies: Dinagat Islands, Surigao del Norte, Surigao del Sur, and Davao Oriental. These provinces face the Pacific Ocean along Mindanao's northeastern and eastern coastlines, making them the first areas to intercept easterly-driven weather disturbances.
Local government units and residents in these provinces — many of which include communities built along riverbanks and on sloping terrain — should maintain heightened vigilance for flash flooding and landslide activity throughout the day, according to the PAGASA bulletin.
The remainder of Mindanao, including major cities such as Davao City, Cagayan de Oro, General Santos, and Zamboanga City, will contend with the same localized thunderstorm pattern covering most of the country, with partly cloudy to cloudy skies and isolated rainshowers or thunderstorms expected.
Winds over Mindanao are forecast to blow from the south to southeast — a slightly different direction from Luzon and Visayas, reflecting the island group's more southerly geographic position and proximity to equatorial wind patterns. Wave heights in Mindanao coastal waters are forecast to be between 0.6 and 1.2 meters, making sea conditions somewhat calmer than those forecast for Luzon and Visayas.
Temperature and Humidity Data: Hot and Humid Conditions Persist
PAGASA's weather station at Science Garden in Diliman, Quezon City recorded observational data for the 24-hour period ending at 8:00 PM on Sunday, June 14. The agency reported a peak temperature of 32.6°C at 5:00 PM and a nighttime minimum of 24.5°C at 2:00 AM.
Relative humidity readings during the same period ranged from a peak of 96% at 5:00 AM to a daytime low of 60% at 2:00 PM, according to PAGASA. This combination of elevated heat and high humidity creates the atmospheric instability that fuels the afternoon thunderstorm development forecast for Monday. Residents should expect the heat index — the perceived or "feels like" temperature — to be considerably higher than actual thermometer readings, particularly during mid-afternoon hours.
Sunrise, Sunset, and Tidal Information for June 15
For Metro Manila, PAGASA places sunrise at 5:27 AM and sunset at 6:26 PM on Monday, giving residents roughly 13 hours of daylight. The moon rises at 5:09 AM and sets at 6:48 PM. Lunar illumination stands at 0%, indicating that Monday falls on a new moon phase.
Tidal data from the National Mapping and Resource Information Authority (NAMRIA) shows a high tide of 1.47 meters occurring at 9:07 AM and a low tide of -0.29 meters at 5:58 PM for Manila Bay. Coastal communities and port operators should factor these tidal levels into their Monday schedules, especially in flood-prone low-lying coastal barangays.
Safety Reminders: How to Stay Safe During Thunderstorms
PAGASA's bulletin explicitly identifies flash floods and landslides as potential hazards for the entire country on Monday — not just the areas under direct easterly influence. Filipinos across all regions are advised to take the following precautions:
Mountain and upland communities: Refrain from traveling through narrow ravines, river crossings, and mountain passes when dark clouds and thunder are present. Landslides can occur with little warning during intense, short-duration rainfall events common in thunderstorms.
Urban and flood-prone low-lying areas: Metro Manila's drainage systems can become overwhelmed during intense downpours. Residents of flood-prone barangays should monitor local water levels closely and be ready to relocate to higher ground if flooding begins to rise rapidly.
Coastal and maritime communities: Fishermen and small vessel operators should take into account the forecast wave heights and the possibility of sudden squalls developing from localized thunderstorms. It is advisable to avoid sea travel during active thunderstorm periods.
PAGASA continues to monitor atmospheric conditions across the archipelago and may issue updated advisories should weather systems intensify beyond current forecast parameters. Residents are encouraged to check the agency's official website and social media channels for real-time updates throughout the day.
Originally reported by: PAGASA / breakingnewsnegros.com