MINDANAO — A low-pressure area (LPA) is expected to bring cloudy skies, scattered rains and thunderstorms over parts of Mindanao, with PAGASA warning of possible flash floods and landslides in areas that receive moderate to at times heavy rainfall.
In its Regional Weather Forecast for Mindanao (MINPRSD) issued at 5:00 a.m. on September 18, 2026, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said the Zamboanga Peninsula, Bangsamoro Autonomous Region in Muslim Mindanao (BARMM), and Northern Mindanao will experience generally cloudy conditions with rainshowers and thunderstorms due to the LPA.
The weather agency warned that moderate to at times heavy rains associated with the weather disturbance could trigger flash floods and landslides, particularly in vulnerable and low-lying areas.
Meanwhile, the rest of Mindanao is expected to have partly cloudy to cloudy skies with isolated rainshowers or localized thunderstorms. PAGASA also cautioned that severe thunderstorms may generate enough rainfall to cause flash floods or landslides.
Zamboanga Peninsula under wetter conditions
The provinces and cities of the Zamboanga Peninsula are among those expected to experience the most persistent adverse weather conditions.
Zamboanga City is forecast to have cloudy skies with rainshowers and thunderstorms, with temperatures ranging from 25°C to 30°C during the first period and reaching as high as 32°C through the following period.
Zamboanga del Norte will likewise experience cloudy skies with rainshowers and thunderstorms, with temperatures of 25°C to 31°C, increasing to as high as 33°C.
In Zamboanga del Sur and Zamboanga Sibugay, temperatures are expected to range from 24°C to 29°C initially, with maximum temperatures reaching 31°C.
Isabela City is forecast to experience similar cloudy conditions, rainshowers and thunderstorms, with temperatures ranging from 25°C to 30°C and later reaching up to 32°C.
Northern Mindanao also faces thunderstorms
The entire Northern Mindanao area is also expected to remain generally wet.
Bukidnon is forecast to have cloudy skies with rainshowers and thunderstorms, with temperatures ranging from 21°C to 28°C, rising to around 30°C.
Camiguin may experience temperatures between 25°C and 29°C, increasing to 31°C, while Lanao del Norte will range from 23°C to 29°C, with temperatures later reaching 31°C.
Misamis Occidental is expected to see temperatures between 23°C and 29°C, increasing to 31°C, while Misamis Oriental may reach 32°C after temperatures initially range from 23°C to 30°C.
All these areas are forecast to experience cloudy skies, rainshowers and thunderstorms.
BARMM provinces to see cloudy skies, thunderstorms
PAGASA also placed the BARMM under a generally cloudy weather pattern, with rainshowers and thunderstorms expected across the region.
Cotabato City is forecast to experience temperatures of 23°C to 29°C, increasing to 31°C.
Basilan may see temperatures between 24°C and 29°C, rising to 31°C, while Lanao del Sur is expected to be among the cooler areas, with temperatures ranging from 20°C to 28°C and later reaching 30°C.
In the island provinces, Sulu is forecast to have temperatures of 25°C to 30°C, increasing to 32°C, while Tawi-Tawi may range from 26°C to 30°C, with a later maximum of 31°C.
Maguindanao del Norte is expected to record temperatures between 24°C and 30°C, rising to 32°C, while Maguindanao del Sur may experience 25°C to 31°C, with temperatures reaching up to 33°C.
Rest of Mindanao may see localized thunderstorms
While the LPA’s effects are expected to be more pronounced over the Zamboanga Peninsula, BARMM and Northern Mindanao, other parts of the island will not be completely free from rain.
Davao Region, including Metro Davao, Davao del Norte, Davao del Sur, Davao Oriental, Davao de Oro and Davao Occidental, is expected to experience partly cloudy skies becoming cloudy at times, with isolated rainshowers or thunderstorms.
Temperatures across the Davao provinces are generally expected to remain between the low 20s and low 30s Celsius, with some areas potentially reaching 33°C.
In SOCCSKSARGEN, North Cotabato, South Cotabato, Sultan Kudarat and Sarangani are likewise forecast to experience partly cloudy to occasionally cloudy skies, with isolated rainshowers or thunderstorms. Temperatures could reach as high as 33°C in Sarangani.
The Caraga Region—including Agusan del Norte, Agusan del Sur, Surigao del Norte, Surigao del Sur and Dinagat Islands—will also experience partly cloudy to at times cloudy skies with rainshowers or thunderstorms. Temperatures in the region may reach 32°C.
Southwest winds, slight to moderate seas
Across Mindanao, winds are forecast to be light to moderate from the southwest.
Coastal waters are expected to remain slight to moderate, with wave heights generally ranging from 0.6 to 2.5 meters.
The combination of rain, thunderstorms and moderate seas means that fishermen, boat operators and other coastal communities should continue to monitor local weather conditions before venturing out to sea.
PAGASA urges vigilance in vulnerable areas
The possibility of flash floods and landslides remains the primary concern as thunderstorms develop over different parts of Mindanao.
Areas with steep terrain, saturated soil, waterways, flood-prone communities and locations affected by previous heavy rainfall may be particularly vulnerable to sudden rises in water levels and rain-induced landslides.
Residents are advised to remain alert to official weather updates and warnings, especially during periods of persistent or heavy rainfall. Local disaster risk reduction and management offices may also issue localized advisories when dangerous conditions develop.
PAGASA’s MINPRSD forecast is valid from 5:00 a.m. September 18 until 5:00 a.m. September 19, 2026.
The weather forecast was prepared by PAGASA forecasters ASS and KJCP through the Mindanao PAGASA Regional Services Division (MINPRSD).