We have now received the reports of three referees and the responses of the authors including a revised manuscript. My general view is that the paper is technically sound and the contents are relevant for the audience of HESS. However, I found the paper hard to read (particularly the methodology part that is very hard to follow) as did reviewers 2 and 3.

There are a number of issues that need consideration, including a better organization and synthesis and a more detailed explanation of methods and physical implications. These issues are listed in the comments by the reviewers, and though I realize that they have been partially addressed by the authors, the revised manuscript still needs further work in this regards.

The study approach section needs considerable reworking. The dot point format is hard to follow and includes few details. Some of the material here should include explanations that are in the results section like, for example, how constrains are implemented. Other aspects that need more explanation are the calibration/optimisation procedure and the determination of parameters of the new formulation.

There are also too many subtitles, the authors should make an effort to provide a section with a better flow and easier to read.

There is also not enough discussion on the physical implications of the newly improved model HyMod V2. Figure 4 is a start but more can be said in the text, particularly in the results or discussion sections.

Please note that, after the revision stage, the revised manuscript and author responses will be sent to the referees to complete the review process.

Best Regards,

Patricia Saco

Dear Authors,
We have now received the reports from the three referees. Two of the referees agree that the paper has been improved and that is now ready for publication. The third referee believes that the modelling study will benefit from further testing. I agree with the third referee, but I think that this further testing could be done and reported in a separately manuscript. The authors have stated this need in the last paragraph of the discussion, but this statement can be further highlighted and strengthened by just slightly changing the wording (as a “need” not just a “potential avenue for research”).

This is a very minor revision that I hope the authors will take into account without the need for further reviews.

Best Regards,
Patricia Saco