KlaroFlowCebu Flood Watch · Historical hazard models
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Historical models · Not a live warning
Explore flood hazards in your area
Choose a place and compare historical river-flood and storm-surge scenarios.
Explore a place
Which place, which hazard, which scenario?
Pick a place on the map or by name. The result shows how much of its land sits in mapped hazard zones for the selected scenario, and whether that scenario covers it.
Choose a place to explore its mapped hazards.
Shares are of land area, not of people, homes or businesses. An uncoloured area is not a safe area.
Approximate depth guide
The source classes are approximately: Low hazard up to 0.5 m, Medium 0.5 to 1.5 m, High over 1.5 m. Hazard also depends on water speed. Shallow, fast-moving water can have a high hazard level. The figure provides scale only; it does not show whether a place or route is safe. PAGASA’s flood guidance →
What the scenario names mean
Rainfall scenarios. The 5-year, 25-year and 100-year rainfall scenarios have an estimated 20%, 4% or 1% chance of being equalled or exceeded in any year. Rare events can occur in consecutive years. These probabilities describe the rainfall scenarios, not the chance that a particular property floods. USGS on return periods →
Storm-surge scenarios 1 to 4 (NOAH SSA). Each layer models a peak storm-tide height: scenario 1 up to 2 m, scenario 2 up to 3 m, scenario 3 up to 4 m, scenario 4 more than 4 m, as defined in the loaded dataset’s metadata. These heights are model inputs at the coast; they are separate from the flood depth at a selected location, which the hazard classes describe.
Compare scenarios
Compare scenarios for a place
Choose a place above to compare how much of its land sits in mapped hazard zones under each scenario.
Compare more places
Shares are of land area in mapped hazard zones for the selected scenario, among places covered by that layer. Tap a place to select it.
Local checks
Three things to check for your place
Short checks you can take to the barangay or city DRRMO. They are based on the mapped scenarios, not on current conditions.
Sources & limits
What these maps can and cannot show
The hazard maps show modelled inundation under set rainfall and storm-surge scenarios, built by Project NOAH from laser-scanned land heights between 2014 and 2017. They do not show where water went in any real storm, and they cannot know about drains, walls or buildings changed since.
River-flood layers carry three classes from the source: Low (about 0 to 0.5 m), Medium (0.5 to 1.5 m) and High (over 1.5 m). The source notes that shallow but fast-flowing water may be given a higher class than its depth alone suggests. Storm-surge layers use the same three classes, judged on depth and on depth times speed.
Storm-surge scenarios 1 to 4 model peak storm-tide heights of up to 2 m, up to 3 m, up to 4 m and more than 4 m, per the loaded dataset’s metadata. PAGASA’s public advisories use a different height scale, so the scenario number here is not an advisory number.
For each barangay, city and municipality: the share of its land inside each hazard class, calculated from the published hazard layers and the PSA boundary files. Results inherit the coverage and limits of those sources. 137 barangays are listed for the three cities; have no outline in the boundary file and are not drawn, so 135 are. Shares are of land area only.
This page is for understanding mapped risk ahead of time, not a live warning. For a warning today, use PAGASA, NDRRMC and your city or municipal DRRMO.
How the models were made
Project NOAH, a programme of the University of the Philippines and PAGASA under DOST, flew laser scanners (LiDAR) over Cebu between 2014 and 2017 to measure land heights to within a few centimetres. From the shape of the land, hydrologists modelled where rain-swollen rivers would spread for three rainfall scenarios, and where the sea would reach for four storm-surge scenarios. The published shapefiles were measured against every barangay and municipal boundary to produce the shares on this page.
Historical storms in Cebu (event accounts, not modelled maps)
Yolanda (Haiyan)
The typhoon crossed Daanbantayan and Bantayan Island hours after a storm surge of 5 to 7 metres struck Tacloban, Leyte. On Bantayan more than 11,000 houses were reported destroyed. Source: AHA Centre repository, Bantayan inundation study.
Odette (Rai)
Field surveys later measured the sea at 2.5 to 4.2 metres above normal along the coasts of Cebu and Bohol. Source: Field Survey of 2021 Typhoon Rai, Journal of Coastal and Riverine Flood Risk.
Tino (Kalmaegi)
Against a November average of about 131 mm for the Cebu City area, rivers including the Butuanon, Mananga, Cansaga and Cotcot overflowed into Mandaue, Talisay, south Cebu City, Consolacion, Liloan and Compostela. More than 100 deaths were reported nationally, most in Cebu. Sources: Al Jazeera, 4 Nov 2025; NDRRMC reporting.
These accounts describe what was observed. The hazard maps on this page were drawn years earlier and are models of scenarios, not of these events.
Licences and credit. River-flood and storm-surge hazard maps: Project NOAH (UP, DOST, PAGASA), made available under the Open Database License (ODbL 1.0). Boundaries: derived from the PSA PSGC via faeldon/philippines-json-maps (MIT). Changes made by KlaroFlow: the land shares in each hazard class were measured from the maps for every place. Under the ODbL, those derived figures, in the page’s data file, are offered under the same ODbL licence. The sources do not endorse KlaroFlow or this page.
Sources and data notes. Everything on this page is public data, calculated from the sources listed above. Found a possible data issue? Tell us which view, place and figure you were looking at so we can review it.
Built on public data by KlaroFlow · Business Analytics & Consultancy, Cebu.