The southwest monsoon — locally known as the habagat — is asserting its presence over the Philippine archipelago on Thursday, June 4, 2026, bringing widespread rains, gusty winds, and rough coastal waters to significant portions of Luzon. PAGASA issued the forecast at 4:00 AM, valid through 4:00 AM on Friday, June 5, 2026, cautioning residents in affected areas about the potential for flash floods and landslides throughout the day.
While the brunt of the monsoon is focused on Luzon — particularly its northern and central regions — no part of the country is entirely spared. The Visayas and Mindanao face a separate but still significant threat from localized thunderstorms that can bring sudden, intense rainfall with little warning.
Luzon: Monsoon Dominates, Multiple Hazards in Play
The southwest monsoon is the primary weather driver across Luzon on Thursday, and its effects vary by location — but hazards are present across nearly the entire island group.
Ilocos Region, Zambales, Bataan, Tarlac, and Pampanga
Residents across the Ilocos Region and the western Central Luzon provinces of Zambales, Bataan, Tarlac, and Pampanga are under the most direct influence of the monsoon's moisture-laden winds. PAGASA forecasts occasional rains for these areas, with the agency warning that moderate to heavy rainfall could trigger flash floods or landslides. Residents near low-lying riverbanks, drainage channels, or unstable hillsides are advised to remain alert and stay away from flood-prone zones.
Metro Manila, Cagayan Valley, CAR, CALABARZON, MIMAROPA, and the Rest of Central Luzon
A broader swath of Luzon — encompassing the capital region and several major population centers — faces more unsettled conditions. Metro Manila, Cagayan Valley, the Cordillera Administrative Region (CAR), CALABARZON, MIMAROPA, and the remaining provinces of Central Luzon can expect cloudy skies with scattered rains and thunderstorms, according to PAGASA.
The agency warns that rainfall in these areas may reach heavy intensity at times, raising the risk of flash floods and landslides. For the millions of commuters and residents in Metro Manila and surrounding provinces, sudden downpours and reduced visibility during thunderstorms are likely to affect road conditions and daily travel. Mountain provinces within CAR — including Benguet, Mountain Province, Ifugao, Kalinga, Abra, Apayao, and Baguio City — face heightened landslide risk given their steep terrain.
"Possible flash floods or landslides due to moderate to at times heavy rains." — PAGASA, 4:00 AM Forecast, June 4, 2026
Visayas and Mindanao: Localized Thunderstorms Remain a Concern
The rest of the country — covering the entire Visayas and Mindanao island groups, as well as portions of Southern Luzon not directly affected by the monsoon — will experience partly cloudy to cloudy skies with isolated rainshowers or thunderstorms on Thursday. These weather disturbances are driven by localized convective systems rather than the southwest monsoon itself.
While the weather in these regions may appear more benign compared to Luzon, PAGASA cautions that severe thunderstorms can still trigger flash floods and landslides in susceptible areas. Residents living near rivers, creeks, or mountainous terrain across the Eastern Visayas, Western Visayas, Central Visayas, Zamboanga Peninsula, Northern Mindanao, Davao Region, SOCCSKSARGEN, Caraga, and the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM) should remain watchful, especially if thunderstorms develop in the afternoon or evening hours.
Localized thunderstorms are particularly deceptive — they can produce intense, concentrated rainfall over a short period in a small area, rapidly overwhelming drainage systems and waterways even when surrounding areas remain dry.
Wind and Coastal Water Conditions
The southwest monsoon is also stirring up significant winds and seas along the western coast of the Philippines. PAGASA reports that Northern Luzon, Central Luzon, and the western section of Southern Luzon will experience moderate to strong winds blowing from the southwest. Coastal waters in these areas are classified as moderate to rough, with wave heights ranging from 1.2 to 3.1 meters.
These sea conditions pose real risks for small fishing vessels and inter-island boats. Fisherfolk and mariners operating along the western coasts of Luzon — including the West Philippine Sea and the waters off Ilocos Norte, Ilocos Sur, La Union, Pangasinan, Zambales, and Bataan — are strongly advised to exercise caution or consider postponing voyages until conditions improve.
For the rest of the country, winds will be light to moderate, blowing from the south to southwest. Coastal waters are expected to be slight to moderate, with wave heights of 0.6 to 1.5 meters — generally manageable for most vessels, though small bancas should still exercise standard precautions.
Temperature: A Warm but Humid Day
Despite the widespread cloud cover and rain, temperatures in Metro Manila remain warm. PAGASA's weather station in Science Garden, Diliman, Quezon City recorded a maximum temperature of 31.5°C at 12:00 noon and a minimum of 25.3°C at 6:00 AM for the 24-hour period ending at 8:00 PM on June 3, 2026. Relative humidity ranged from 64% to 95%, reflecting the moist air mass associated with the southwest monsoon. Residents should expect a muggy feel throughout the day, even during breaks in the rain.
Tides and Astronomical Information for Metro Manila
For Metro Manila, tidal predictions courtesy of NAMRIA indicate a high tide of 1.23 meters at 11:42 AM and a low tide of -0.12 meters at 8:41 PM on Thursday. Sunrise is at 5:26 AM and sunset at 6:23 PM. The moon is at 85% illumination, with moonrise at 9:41 PM and moonset at 8:21 AM.
Safety Advice for Thursday
PAGASA's forecast carries specific hazard warnings that Filipinos nationwide should take seriously. Flash floods can develop rapidly — even within minutes of a heavy downpour — in low-lying and flood-prone areas. Landslides are a particular concern in mountainous and hilly terrain, especially where soil has already been saturated by earlier rains.
Residents in all affected areas are encouraged to take the following precautions:
Stay informed: Monitor the latest PAGASA updates throughout the day, as weather conditions can change rapidly. Local government units (LGUs) may issue additional advisories.
Avoid flood-prone areas: Do not attempt to cross flooded roads or waterways, even if the water appears shallow. Fast-moving floodwater can be far more powerful than it looks.
Heed evacuation orders: If local authorities issue evacuation advisories — particularly in landslide-prone barangays in Luzon's mountain provinces — comply promptly and do not wait for the situation to worsen.
Mariners and fisherfolk: Those along the western coast of Luzon should avoid venturing into rough coastal waters. Waves of up to 3.1 meters can capsize small vessels without warning.
Motorists and commuters: Expect reduced visibility during thunderstorms and the possibility of flooded underpasses and streets, particularly in Metro Manila and other urban areas. Allow extra travel time and avoid routes known to flood easily.
The 24-hour public weather forecast issued by PAGASA at 4:00 AM on June 4, 2026 remains valid until 4:00 AM on June 5, 2026. Updates will be issued as conditions warrant.
Monitor official PAGASA updates at pagasa.dost.gov.ph.