The Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) has released its May 2026 rainfall forecast for Mindanao, indicating generally near-normal conditions across the island, though some areas may experience above-average precipitation.
Rainfall Outlook for May 2026
According to Pagasa, most parts of Mindanao are expected to record rainfall within the normal range, with monthly totals largely aligning with historical averages. However, localized variations are likely, particularly in western Mindanao where above-normal rainfall is possible.
Expected Rainfall Distribution
Forecast data show that central and southeastern Mindanao, including Davao Region provinces such as Davao de Oro, Davao del Norte, and Davao del Sur, as well as parts of Bukidnon, Agusan del Sur, Surigao del Sur, and Cotabato may receive between 200 to 300 millimeters of rainfall throughout the month.
Meanwhile, western and northern sections of Mindanao, including areas in the Zamboanga Peninsula, Northern Mindanao, and parts of Caraga, are projected to experience relatively lower rainfall, ranging from 100 to 200 millimeters.
Areas with Above-Normal Rainfall
Despite the generally normal outlook, Pagasa noted that certain areas could see above-normal rainfall levels. These include portions of the Zamboanga Peninsula, areas within the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM), particularly Maguindanao del Norte and Maguindanao del Sur, as well as Lanao del Norte, Lanao del Sur, South Cotabato, and Sarangani.
Weather Systems Influencing Rainfall
The state weather bureau attributed the expected rainfall patterns to a combination of prevailing weather systems that typically affect the country during this time of year. These include localized thunderstorms, easterlies, the intertropical convergence zone (ITCZ), shear line events, and the possible development of low-pressure areas or tropical cyclones.
Pagasa also indicated that the southwest monsoon, locally known as “habagat,” may begin to influence weather conditions toward the latter part of May, potentially increasing rainfall in some parts of the island.
Comparison with Normal Climate Patterns
Historically, rainfall in May across Mindanao varies depending on location. Based on climatological data from 1991 to 2020, higher rainfall amounts ranging from around 200 to 300 millimeters are typically observed in central and southeastern areas, including parts of Davao Region, Bukidnon, Cotabato, Maguindanao, Agusan del Sur, and Surigao del Sur.
In contrast, western and northern Mindanao, such as the Zamboanga Peninsula and portions of Northern Mindanao, usually receive moderate rainfall between 100 and 200 millimeters. The current forecast aligns closely with these long-term averages, reinforcing expectations of near-normal conditions across much of the island.
Advisory to the Public
While no extreme deviations from normal rainfall are expected on a regional scale, Pagasa cautioned that localized weather disturbances may still bring heavy rains over short periods, potentially leading to flooding or landslides in vulnerable areas.
The agency urged the public, especially those in flood-prone and landslide-prone communities, to remain vigilant and regularly monitor official weather updates and advisories. As Mindanao enters the transition period toward the rainy season, authorities emphasize the importance of preparedness, noting that even within a “normal” rainfall outlook, weather conditions can shift rapidly due to developing systems.
