GENERAL SANTOS CITY — Widespread rainshowers and thunderstorms are expected across several parts of Mindanao as the Intertropical Convergence Zone (ITCZ) continues to influence the region, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).
In its 5:00 a.m. regional weather forecast issued on September 16, 2026, PAGASA’s Mindanao PAGASA Regional Services Division (MINPRSD) said the weather outlook is valid from 5:00 a.m. Wednesday until 5:00 a.m. Thursday, September 17.
The weather agency forecast cloudy skies with scattered rains and thunderstorms over the Zamboanga Peninsula, Northern Mindanao, Caraga, Lanao del Sur and Davao Oriental due to the prevailing ITCZ.
PAGASA warned that flash floods and landslides are possible in areas affected by moderate to at times heavy rainfall, particularly in communities near rivers, waterways, steep slopes and other flood- or landslide-prone locations.
The rest of Mindanao is expected to experience partly cloudy to cloudy skies with isolated rainshowers or thunderstorms. PAGASA likewise cautioned that flash floods or landslides may occur during severe thunderstorms.
Zamboanga Peninsula under rainy conditions
The entire Zamboanga Peninsula is expected to experience generally cloudy conditions accompanied by rainshowers and thunderstorms.
In Zamboanga City, temperatures are forecast to range from 23°C to 30°C during the initial forecast period, increasing to as high as 33°C during the succeeding period.
Zamboanga del Norte, Zamboanga del Sur and Zamboanga Sibugay are expected to record temperatures ranging from 22°C to 29°C, with maximum temperatures reaching 32°C in the following period.
Isabela City is forecast to experience temperatures between 23°C and 30°C, rising to as high as 33°C.
Winds across the peninsula will generally be light to moderate from the south to southwest, while coastal waters are expected to remain slight to moderate.
Northern Mindanao faces thunderstorms
Cloudy skies with rainshowers and thunderstorms are also expected over Northern Mindanao, including Bukidnon, Camiguin, Lanao del Norte, Misamis Occidental and Misamis Oriental.
Bukidnon is forecast to have the coolest temperatures among the listed areas, with temperatures ranging from 19°C to 28°C and potentially reaching 31°C during the following forecast period.
Camiguin, Lanao del Norte, Misamis Occidental and Misamis Oriental are expected to register temperatures generally between 22°C and 29°C, with daytime highs of up to 32°C.
Residents in areas vulnerable to flooding and landslides are advised to remain alert as thunderstorms may bring sudden periods of intense rainfall.
Davao Region to see intermittent rainshowers and thunderstorms
Much of the Davao Region will have partly cloudy skies that may become cloudy at times, with rainshowers or thunderstorms possible throughout the forecast period.
Metro Davao is expected to experience temperatures between 24°C and 31°C, with temperatures potentially reaching 33°C in the following period.
Davao del Norte is forecast to be among the warmer areas, with temperatures ranging from 24°C to 32°C and reaching as high as 34°C.
Davao del Sur may see temperatures between 24°C and 31°C, rising to about 33°C.
Unlike much of the region, Davao Oriental is expected to have cloudy skies with rainshowers and thunderstorms, with temperatures ranging from 23°C to 29°C and reaching as high as 32°C.
The previous afternoon forecast also placed Davao de Oro and Davao Occidental under partly cloudy to at times cloudy conditions with possible rainshowers or thunderstorms. Both provinces are expected to have temperatures reaching up to 32°C during the succeeding forecast period.
Caraga remains prone to rain and thunderstorms
The Caraga Region is also expected to experience generally cloudy skies with rainshowers and thunderstorms as the ITCZ affects the area.
Agusan del Norte and Agusan del Sur are forecast to have temperatures from 23°C to 29°C, with highs of up to 32°C.
Surigao del Norte is expected to have similar conditions, with temperatures ranging from 23°C to 29°C and reaching up to 32°C.
Surigao del Sur may experience slightly warmer conditions, with temperatures ranging from 23°C to 30°C and reaching as high as 33°C.
The Dinagat Islands is likewise expected to have cloudy skies with rainshowers and thunderstorms, with temperatures between 23°C and 29°C, rising to around 32°C.
Given the potential for moderate to heavy rainfall, authorities and residents in flood- and landslide-prone areas are urged to closely monitor local conditions, particularly when thunderstorms intensify.
SOCCSKSARGEN to experience localized thunderstorms
Areas in SOCCSKSARGEN are generally expected to experience partly cloudy skies that may become cloudy at times, with rainshowers or thunderstorms.
North Cotabato is forecast to have temperatures between 24°C and 30°C, with highs reaching 32°C.
South Cotabato and Sarangani are expected to have temperatures ranging from 23°C to 30°C and 24°C to 30°C, respectively, with both areas potentially reaching 32°C.
Sultan Kudarat may experience slightly cooler temperatures, ranging from 23°C to 29°C, with daytime highs of about 31°C.
Although the general forecast calls for partly cloudy conditions, thunderstorms may develop suddenly, bringing short periods of heavy rain and potentially hazardous conditions.
BARMM areas also affected
Several areas of the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM) are likewise expected to experience rainshowers and thunderstorms.
Cotabato City is forecast to have cloudy skies with rainshowers and thunderstorms, with temperatures ranging from 23°C to 29°C and reaching up to 32°C.
Basilan is expected to have temperatures between 23°C and 28°C, rising to about 31°C.
Lanao del Sur, which is specifically identified by PAGASA as one of the areas expected to experience cloudy skies with scattered rains and thunderstorms, may record temperatures from 21°C to 28°C, with highs of around 31°C.
The earlier forecast also placed Sulu and Tawi-Tawi under cloudy skies with rainshowers and thunderstorms. Sulu is expected to range from 23°C to 28°C, while Tawi-Tawi may see temperatures between 24°C and 28°C, with both areas potentially reaching around 31°C.
Meanwhile, Maguindanao del Norte and Maguindanao del Sur are expected to have partly cloudy to at times cloudy skies, with rainshowers or thunderstorms possible. Temperatures may reach 33°C in both provinces.
Winds and coastal conditions
PAGASA said light to moderate winds from the south to southwest are expected across Mindanao during the forecast period.
Coastal waters in areas where conditions were specified are generally expected to remain slight to moderate, with wave heights ranging from approximately 0.6 to 2.5 meters.
The combination of rain, thunderstorms and moderate seas may affect small fishing boats and other light watercraft, particularly during periods of stronger thunderstorms.
Residents urged to monitor local warnings
PAGASA emphasized that the ITCZ can produce localized heavy rainfall and thunderstorms, meaning weather conditions may vary considerably even within the same province or locality.
Communities located in low-lying and flood-prone areas, along river channels, near waterways and on or below steep and unstable slopes should remain vigilant for rapidly changing conditions.
Residents are advised to monitor official weather bulletins and warnings, particularly during thunderstorms, and to follow instructions from local disaster risk reduction and management offices when flooding or landslide risks increase.
Motorists should also exercise caution on roads affected by heavy rain, reduced visibility or flooding, while coastal communities and small-craft operators should closely monitor sea and thunderstorm conditions before venturing offshore.
PAGASA’s regional forecast remains valid until 5:00 a.m. on September 17, 2026, with subsequent bulletins expected to provide updated weather conditions and forecasts for Mindanao.
Source: Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) – Mindanao PAGASA Regional Services Division (MINPRSD)