Typhoon Ompong (international name: Mangkhut) made its landfall in Baggao, Cagayan last September 15, causing heavy rainfall and bringing winds of over 200 km per hour. The typhoon reportedly caused PhP21.3 billion (B) worth of damages to agriculture and public infrastructure, according to the National Disaster Risk Reduction and Management Council (NDRRMC). The amount is divided between the agriculture sector with a total damage of PhP14.3B, and public infrastructure with PhP6.9B.
Areas affected by the typhoon included Regions I, II, III, Calabarzon, Mimaropa, V, CAR and NCR. Details of the damage are as follows:
| Particulars | Region | Numbers affected and Estimated Value |
| Agriculture | ||
| Rice | I, II, III, Calabarzon, CAR | • Ilocos Norte: PhP2.1B• Cagayan: PhP2.8B
• Isabela: PhP816.8 million (M) • Nueva Vizcaya: PhP43.0M • Qurino: PhP2.9M • Aurora: PhP51.5M • Bulacan: PhP5.0M • Nueva Ecija: PhP2.8B • Zambales: PhP2.5M • Quezon: PhP2.7M • Cavite: PhP66,250 • Rizal: PhP7.8M • Abra: PhP 7.6M • Apayao: PhP15.8M • Benguet: PhP2.0M • Ifugao: PhP11.9M • Kalinga: PhP329.1M • Mt. Province: PhP3.6M |
| Corn | II, III, CAR | • Region II: PhP2.7B• Aurora: PhP16.7M
• Abra: PhP237,546 • Apayao: PhP70.3M • Ifugao: PhP997.4M • Kalinga: PhP723.0M • Mt. Province: PhP7.4M |
| Public Infrastructure and Families Affected | ||
| Road sections | I, II, III, V, CAR | 325• 296 were reported passable |
| Bridges | I, II, III, V, CAR | 8• 6 bridges were reported passable |
| Homes | I, II, III, CAR | 140,886• 130,024 (partially)
• 10,862 (totally) |
| Persons affected | I, II, III, Calabarzon, Mimaropa, NCR, CAR | 2.4M (561,255 families) |
Source: NDRRMC (as of September 26, 2018)
Eight provinces and a total of seven cities/municipalities were declared to be under the state of calamity.