The Peruvian Service of Meteorology and Hydrology (SENAMHI) provides hydro-climatological hazard information to population and decision-makers about flood forecasting and warning on the whole territory of Peru. For flash floods monitoring, a sub-daily simulation is critical to properly address the response of the watershed and prepare timely flash flood warnings. Over the last
years, the city of Tumbes has been affected by the overflowing of Puyango-Tumbes river, which is born in Ecuador and flows to northwestern Peru. For this reason, the aim of this work is to develop an operational sub-daily hydrological forecast service for Puyango-Tumbes river basin.