The manuscript provides a valuable analysis of rainfall-driven flood risks from hurricanes in Puerto Rico under current and projected climate warming scenarios. The topic is timely and of significant importance, given the vulnerability of Puerto Rico to climatic extremes. The manuscript is well-written and methodologically sound and provides a significant contribution to the understanding of climate impacts on flood risks in small island regions. However, there are a few aspects of the manuscript that require further attention and clarification before publication. I have provided a few editorial comments on the PDF. Here are my main comments.

1. Please specify the future climate scenarios (CMIP5/6; SSPs/RCPs).
2. Lines 416-418: The basic information on these models is critical for interpreting the results. I recommend that the authors summarize the basic information about the GCMs, including their resolution. This information will enhance the reader's understanding of GCMs applied in the study.
3. This study does not incorporate storm surge component in the modeling process. Rappaport (2014) has highlighted that storm surge accounts for roughly half of the fatalities from Atlantic hurricanes in the US between 1963 and 2012. The authors should offer a comprehensive rationale for excluding storm surge from the model and discuss the implications this may have on the validity and applicability of the study's findings.
4. The manuscript would be improved by the inclusion of a flowchart that delineates the methodology for generating synthetic hurricane rainfall events. Given that the terms 'synthetic hurricane event' and 'hurricane rainfall event' can be easily misunderstood, a visual representation would greatly assist in distinguishing these terms and clarifying the approach used in the study.
5. The choice of the future data period (2106 - 2115) needs further explanation. The rationale behind selecting this particular decade should be elucidated to justify its relevance to the scenarios under investigation.
6. While IMERG and NCEP datasets are used as observational data sources, there is no discussion about their reliability or the uncertainties associated with satellite data. Authors should elaborate on these aspects, possibly including error metrics or validation studies, to affirm the credibility of these data sources and their suitability for this analysis.
7. In Figure 6, it is recommended that the range of the x-axis be consistent across all four results to facilitate a straightforward fair comparison. This will improve the figure readability and allow for a clearer interpretation of the data presented.
8. Section 5 should be entitled “Conclusions” (plural).
9. In the SI, please clarify what satellite imagery was used when evaluating the HWMs.

I hope the authors find these comments useful in their research.

The authors used forcings of a synthetic hurricane rainfall simulator as inputs to LISFLOOD-FP hydrodynamic model to estimate flood inundation maps in Puerto Rico. Magnitude in precipitation simulations are adjusted to expected changes due to warming under future 1.5C and 2C scenarios. Model results allow to estimate the increase in population that is exposed to flooding.

I enjoyed a lot reading and reviewing this manuscript. It is very well written, the methodology is sound, and addresses the problem of changes in flooding in small islands, where more scientific literature is very needed.

I think the manuscript is ready for publication in its current state. I only have minor questions that might be clarified in the manuscript.

The manuscript could benefit from including a chart describing the methodology, the path from climate forcing to flood inundation maps.

Are MRMS precipitation estimates available for Puerto Rico. If so, could those be used as a substitute for Stage IV which has coarser resolution ? MRMS have shorter availability than Stage IV, but includes a better QPE algorithm and finer spatial resolution (1km).

I didn’t find any typing errors along the manuscript.