Help with RAINHHMX calculation – daily rainfall data only

[Σπυριδούλα Τσουρναβέλη]

Hello everyone,

My name is Spyridoula Tsournaveli , I am a university student working on my diploma thesis using QSWAT.
I am currently preparing the .wgn weather generator file for my watershed, but I have encountered a difficulty regarding the parameter RAINHHMX(mon).

According to the SWAT documentation, RAINHHMX represents the maximum 0.5-hour rainfall intensity recorded for each month. However, I only have daily precipitation data (1 value per day) for all years in my study period, and no sub-daily (hourly) rainfall records are available for my region.

My questions are:

1. How should RAINHHMX(mon) be calculated when only daily rainfall data exist?

2. Does QSWAT automatically handle this in any way, or must the value be explicitly provided in the .wgn file?

If you have any guidance, documentation references, or example workflows, it would be extremely helpful for my thesis.

Thank you very much in advance!
Spyridoula Tsournaveli
Student – Diploma Thesis Research