On 7 October, a Low-Pressure Area East of Camarines Norte developed into a tropical depression while moving erratically over the Philippine Sea, and on the following day intensified into a Tropical Storm called Kompasu (locally known as Maring). On 10 October, Tropical Storm Kompasu merged with a Tropical Depression (locally known as Nando) and continued moving towards the Extreme Northern Luzon.
On 11 October, Tropical Storm Kompasu intensified into Severe Tropical Storm (STS) and passed close to south of Camiguin Island, after which it made a landfall in the vicinity of Fuga Island, Cagayan in Region II. It further enhanced the southwest monsoon, bringing more rain to already inundated areas and causing heavy flooding in Cagayan Valley, MIMAROPA and Cordillera Administrative Region (CAR). Although, the Severe Tropical Storm exited the Philippine Area of Responsibility (PAR) on Tuesday 12 October, further heavy rains were experienced.
National Disaster Risk Reduction and Management Council has reported a total of 235 flooded areas and 31 incidents of rain-induced landslides in Regions I, II, III, MIMAROPA, CARAGA and CAR. Flooding up to waist level has been caused by continuous rains and the high saturation of soil moisture. A total of 155,156 families or 611,705 persons affected in 1,380 barangays in Regions I, II, III, MIMAROPA, VI, CARAGA and CAR with 39 dead, 3 injured and 17 missing. At least 4,318 families or 15,130 persons are currently taking temporary shelter in 91 evacuation centres. (IFRC, 19 Oct 2021)
As of 20 Oct, TC KOMPASU caused the following in the Philippines: 248,263 families (940,847 persons) affected in 1,788 barangays, 130,035 people displaced (1,775 in 60 evacuation centres), 41 dead, 17 missing, and 5 injured. 1,418 families (5,461 persons) were preemptively evacuated and 1.76M USD worth of assistance has been provided to victims in Region 1, 2, 3, MIMAROPA, and CAR. In Thailand, the Department of Disaster Prevention and Mitigation (DDPM) reported that the influence of TC KOMPASU, from the 15th to the 17th of October, has resulted in flash floods and flooding: 3,326 households (estimated 16,630 persons) affected in six provinces (Tak, Phetchabun, Chaiyaphum, Lopburi, Prachinburi, Nakhon Nayok). As of 21 October, the situation has been resolved in four provinces (Tak, Phetchabun, Chaiyaphum, and Nakhon Nayok) and persists in Lopburi and Prachinburi. (AHA Centre, 21 Oct 2021)
As of 31 October, a total of 1,140,534 people affected in 1,977 barangays in Regions I, II, III, MIMAROPA, VI, CARAGA and CAR according to the National Disaster Risk Reduction and Management Council (NDRRMC) and Department of Social Welfare and Development – Disaster Response Operations Monitoring and Information Center (DSWD - DROMIC). At least 43 dead, 5 injured and 16 missing. More than 25,000 people took temporary shelter in 371 evacuation centres. Estimated PHP 2.6 billion (CHF 46.5 million) worth of damage to crops, livestock and agricultural infrastructure and equipment; with close to 50,000 livestock and poultry lost. (IFRC, 15 Nov 2021)