Storm Surge

A storm surge is the wall of seawater a typhoon pushes ahead of itself onto land. It is not the same as flooding from rain; it is the ocean itself arriving inland. This layer tells coastal-property buyers whether the sea reaches their lot, and in what kind of storm.

NOAH maps surge in four advisory levels, SSA1 through SSA4, where higher numbers mean the surge from a stronger, rarer storm. A lot flagged at SSA1 is reachable even in a typical typhoon; one flagged only at SSA4 is reachable only in a worst-case super-storm.

Typhoon Yolanda (Haiyan, 2013) drove a storm surge several meters high into Tacloban and the surrounding coast. The surge, more than the wind, is what caused most of the thousands of deaths. Many residents did not understand that "storm surge" meant the sea would come for them.

The Philippines has one of the longest coastlines in the world, and coastal land is some of the most sought-after. This layer exists so that a beautiful sea view does not hide the fact that the same sea has a mapped path to the front door.

We test your point against the NOAH storm-surge polygons and return the highest advisory level (SSA1-4) that reaches it.

Inland addresses well away from the coast simply read as outside every surge band, and the layer stays quiet rather than cluttering the report.

Storm-surge advisory bands come from the UP NOAH Center / DOST nationwide modelling.

Surge sits alongside flood and waterway proximity in the report's flood-insurance ladder, because carriers treat all three as one combined water peril.