Thunderstorms and isolated rain showers are set to sweep across the entire Philippines on Wednesday, June 17, 2026, with the national weather agency warning of possible flash floods and landslides if severe thunderstorms develop. PAGASA issued its 24-hour public weather forecast at 4:00 AM, valid through 4:00 AM on Thursday, June 18.
No tropical cyclone is influencing the country's weather at this time. Instead, two separate weather drivers are at work: the easterlies affecting eastern portions of the Visayas and Mindanao, and localized convective thunderstorms covering Metro Manila and the rest of the archipelago. The result is a nationwide weather picture dominated by cloud cover, intermittent downpours, and the threat of severe weather in vulnerable communities.
National Weather Overview
According to PAGASA, all major island groups — Luzon, Visayas, and Mindanao — will experience partly cloudy to cloudy skies with isolated rain showers or thunderstorms throughout the day. While the rain may not fall continuously, thunderstorms can develop quickly and intensify, particularly during the afternoon and early evening hours when surface heating is at its peak.
PAGASA specifically flagged the risk of flash floods and landslides during severe thunderstorms across all affected areas. This hazard is particularly relevant for residents living near rivers, drainage channels, and hillside communities, who should monitor weather conditions closely and heed any local government evacuation advisories.
Luzon Forecast
Metro Manila and the rest of Luzon can expect partly cloudy to cloudy skies with isolated rain showers or thunderstorms on Wednesday. These weather disturbances are attributed to localized thunderstorms — weather systems that build up due to daytime heating and atmospheric moisture rather than an organized weather system or tropical cyclone.
Residents across the National Capital Region, as well as provinces throughout Luzon — from the Ilocos Region and Cagayan Valley in the north, through Central Luzon and CALABARZON, down to Bicol in the south — should anticipate the possibility of sudden, heavy downpours during the day. Flash flooding in low-lying urban areas and landslides in mountainous provinces remain a concern wherever thunderstorms are severe.
Winds over Luzon will be light to moderate, blowing from the southeast to southwest. Coastal waters surrounding Luzon are classified as slight to moderate, with wave heights ranging from 0.6 to 1.8 meters. Mariners and fisherfolk should exercise caution, particularly during periods of active thunderstorm activity when sea conditions can deteriorate rapidly.
Visayas Forecast
The Visayas region will see a mix of weather influences on Wednesday. Eastern Visayas — which includes the provinces of Samar, Eastern Samar, Northern Samar, Leyte, Southern Leyte, and Biliran — will experience partly cloudy to cloudy skies with isolated rain showers or thunderstorms driven specifically by the easterlies. These easterly winds, blowing in from the Pacific Ocean, carry significant moisture that can fuel persistent cloud cover and rain activity along the eastern seaboard.
The rest of the Visayas, including Central Visayas and Western Visayas, will also contend with partly cloudy to cloudy skies and isolated thunderstorms attributed to localized convection.
As with Luzon, PAGASA warns that severe thunderstorms across the Visayas may produce flash floods and landslides. Residents in Leyte, Samar, and other provinces with known flood-prone and landslide-prone areas should remain especially vigilant.
Winds over the Visayas are light to moderate, coming from the southeast to southwest. Coastal waters in the region are slight to moderate, with wave heights of 0.6 to 1.8 meters.
Mindanao Forecast
In Mindanao, the weather picture is similarly unsettled. Eastern Mindanao — specifically Dinagat Islands, Surigao del Norte, Surigao del Sur, and Davao Oriental — will experience partly cloudy to cloudy skies with isolated rain showers or thunderstorms due to the easterlies. These provinces, facing the Pacific Ocean, are directly in the path of the moist easterly flow and may see more persistent cloud cover and rainfall activity compared to other parts of the island.
The remainder of Mindanao, including the rest of the Davao Region, the Soccsksargen region, the Zamboanga Peninsula, Northern Mindanao, the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM), and the Caraga region outside the provinces already mentioned, can expect partly cloudy to cloudy skies with isolated rain showers or thunderstorms due to localized thunderstorms.
PAGASA's flash flood and landslide warning applies to Mindanao as well. Communities in mountainous areas of Compostela Valley, Bukidnon, and other elevated provinces, as well as those near major river systems, are advised to stay alert throughout the day.
Wind conditions over Mindanao differ slightly from Luzon and Visayas. Winds will be light to moderate but will blow from the east to northeast — reflecting the direct influence of the easterly wind flow over the southern Philippines. Coastal waters around Mindanao are slight to moderate with wave heights of 0.6 to 1.2 meters, somewhat calmer than those farther north.
Temperature and Humidity
PAGASA recorded the temperature extremes for Metro Manila at its weather station in Science Garden, Diliman, Quezon City, for the 24-hour period ending at 8:00 PM on Tuesday, June 16. The maximum temperature reached 34.0°C at 2:00 PM, while the minimum temperature was recorded at 25.4°C at 5:00 AM. Relative humidity ranged from a high of 94 percent at 5:00 AM to a low of 56 percent at 11:00 AM, indicating generally humid conditions typical of the wet season.
Despite the threat of rain, residents can expect temperatures to remain warm during dry spells in the day, with the heat index — or the "feels like" temperature when humidity is factored in — potentially making conditions feel significantly hotter than the recorded temperature.
Astronomical and Tidal Information for Metro Manila
For Metro Manila, the sun rises at 5:27 AM and sets at 6:27 PM on Wednesday, June 17. Moonrise is at 7:26 AM and moonset at 8:50 PM, with an 8 percent lunar illumination, meaning nights will be predominantly dark — a factor to keep in mind for communities relying on natural light.
Tidal predictions for Manila Bay, provided courtesy of NAMRIA, show a high tide of 1.55 meters at 10:49 AM and a low tide of -0.28 meters at 7:45 PM on Wednesday. Coastal and low-lying bayside communities in the Manila Bay area should be aware of these tidal movements, particularly in the context of any heavy rainfall that could combine with high tide to worsen localized flooding.
Safety Reminders
With flash floods and landslides cited as potential hazards by PAGASA across all regions, the public is urged to take the following precautions throughout Wednesday:
Avoid crossing flooded roads, bridges, and waterways, as floodwaters can be deeper and faster-moving than they appear. Residents in landslide-prone hillside communities should heed any advisories from their local government units and be prepared to evacuate if necessary. Motorists should slow down and increase following distances during heavy rain, when visibility is reduced. Those along coastal areas should take note of wave heights and avoid unnecessary sea travel during periods of thunderstorm activity.
"Possible flash floods or landslides during severe thunderstorms" — PAGASA, 24-Hour Public Weather Forecast, 4:00 AM, June 17, 2026
PAGASA will issue updated forecasts as conditions evolve. The public is encouraged to rely on official PAGASA channels for the latest weather information and avoid unverified reports on social media.
Monitor official PAGASA updates at pagasa.dost.gov.ph