WXSIM and extreme weather events

We’re going through rather extreme weather events lately. WXSIM was rather successful in forecasting the precipitation. I made a short comparison between the forecast/actual values. I averaged 4 forecast runs one day ahead of expected event. Both of them happened in the last 7 days.

Forecast / Actual
Event 1: 103 mm / 163 mm
Event 2: 156 mm / 150 mm

For tomorrow, we’re expecting another event. WXSIM keeps calculating accumulation over 300 mm in about 12-24 hours. Other sources (e.g. ICON-D2) suggest less than 150 mm.

300 mm would cause major damage due to previous rain (700 mm last few weeks) so I’m worried whether to believe WXSIM or ECMWF, ICON-D2.

In others’ experience, how good is WXSIM in these circumstances? Have anyone undergo similar events?

Just curious, what is your location. You have no info in your profile.
I’m also curious what GFS Model is saying for another comparison to those you mentioned.
Kindest Regards,

I’ll PM my location. Models (GFS, ECMWF) forecast in range of 150 mm.

In the latest event, the WXSIM consistently forecast accumulation ranging from 330-450 mm. We finally got 120 mm. This is a significant difference which may cause some confusion. I’m thinking if I have something enabled/disabled which made such calculation outputs… For the next event in 2 days the precipitation accumulation looks reasonable and in line what the models say.

A follow up to the topic:
Tom had taken a look at my settings and found out an important issue. I had set the orographic effect too high which caused (in combination with the wind) a large overestimate. There were other issues which I corrected and am looking toward better forecasts.
Not an issue with the software but with its inexperienced user :slight_smile:

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