SUEWS Simple in QGIS Crashes After Data Fields Auto-Changing

[biglimp]

Discussed in #803

^{Originally posted by reeveugm December 11, 2025}
Hi everyone, I’m experiencing an issue when trying to run SUEWS Simple using the UMEP and UMEP for Processing plugins in QGIS.

I entered all the required input parameters—coordinate conditions (which I calculated myself), forcing data directory, and output folder—into the SUEWS Simple window. Everything looks normal at first (as shown in the screenshot).

When I click Run, a small progress window appears (which I assume is normal), like this.

but then the SUEWS Simple form suddenly changes. The values I previously entered are replaced with something that looks very similar to the data from “Add settings from test dataset”, even though I never clicked that option.

After 2–3 seconds, QGIS completely crashes and closes.

Has anyone experienced this issue?
What could be causing the input fields to change automatically right before the crash?
Is this due to a bug, a data formatting issue, or something wrong with my setup?

Any insight or troubleshooting suggestions would be greatly appreciated. Thank you!

[biglimp]

Version 3.40, supy 2025.7.9.dev0

[biglimp]

@reeveugm , what version of UMEP are you using?

[reeveugm]

I used UMEP version 4.4.3 and UMEP for Processing version 2.2.3

[biglimp]

Try the development release just pushed to the SuPy-QGIS3 branch. That just fixed the issue that the GUI changed values. See here how you do this: https://umep-docs.readthedocs.io/en/latest/Getting_Started.html#installing-development-release-could-be-unstable

I cannot replicate your QGIS crash but I have a newer version of the model that you. You could try to update using:
pip install supy==2025.11.20rc1
Here are instructions on how to do this: https://umep-docs.readthedocs.io/en/latest/Getting_Started.html#adding-missing-python-libraries-and-other-osgeo-functionalities

[reeveugm]

Sorry for taking some time to try different things, even though none of them have been successful so far. Below are my attempts to make it work. I honestly don’t know whether the issue is caused by my system or by the plugin itself.

1. I tried installing UMEP and UMEP for Processing using the zipped GitHub repositories from the link you provided. However, an error window keeps popping up when QGIS starts. The error looks like this:
   Couldn't load plugin 'UMEP-SuPy-QGIS3' due to an error when calling its classFactory() method ModuleNotFoundError: No module named 'supy.data_model'
   I asked ChatGPT about this, and it suggested using QGIS 3.28 LTR (Firenze). I tried again using Firenze, but it still didn’t work. Apparently, this setup requires supy 2022.4.7, which in turn depends on supy-driver==2021a5, and that version is no longer available on PyPI.
2. I then stopped using Firenze and tried to reproduce the setup that I remember working previously. I installed it around February, and based on my recollection, the working combination was:

• QGIS 3.40.4 (Bratislava)
• UMEP 4.1.1
• UMEP for Processing 2.0.35
  I’m not sure which SuPy version is supposed to match this combination. When I tried installing SuPy, it ended up using something like 2024.5.7.dev (if I remember correctly). With this setup, it still doesn’t work, and every time I run SUEWS Simple, a popup appears showing a NoneType error.everytime i run suews simple.

3. I then tried again using supy 2025.11.20 (at QGIS 3.40.13), since 2025.11.20rc1 is not available via pip and I couldn’t find it in the OSGeo shell either. After clicking Run in SUEWS Simple, the following error appears in the log messages:
   2025-12-15T16:53:19 WARNING Traceback (most recent call last): File "C:\Users\Acer\AppData\Roaming\QGIS\QGIS3\profiles\default\python\plugins\UMEP\SuewsSimple\suews_simple.py", line 430, in start_progress with open(self.supylib + '/sample_run/sample_config.yml', 'r') as f: FileNotFoundError: [Errno 2] No such file or directory: 'C:\Users\Acer\AppData\Roaming\Python\Python312\site-packages\supy\sample_run\sample_config.yml'
   I’m not sure whether this error is the reason why the Run button is trying to fetch the sample data instead of using the selected input data.
4. Finally, I tried again using:

• QGIS 3.40.13
• UMEP 4.4.3
• UMEP for Processing 2.2.3
• SuPy 2025.7.9.dev
  With this setup, clicking Run changes the dataset from the sample data to the input data, and then QGIS crashes just like i explained in the main post.

At this point I’m a bit confused about where the problem really is. Thanks a lot for your help.

[biglimp]

Sorry for taking some time to try different things, even though none of them have been successful so far. Below are my attempts to make it work. I honestly don’t know whether the issue is caused by my system or by the plugin itself.

1. I tried installing UMEP and UMEP for Processing using the zipped GitHub repositories from the link you provided. However, an error window keeps popping up when QGIS starts. The error looks like this:
   Couldn't load plugin 'UMEP-SuPy-QGIS3' due to an error when calling its classFactory() method ModuleNotFoundError: No module named 'supy.data_model'
   I asked ChatGPT about this, and it suggested using QGIS 3.28 LTR (Firenze). I tried again using Firenze, but it still didn’t work. Apparently, this setup requires supy 2022.4.7, which in turn depends on supy-driver==2021a5, and that version is no longer available on PyPI.

2. I then stopped using Firenze and tried to reproduce the setup that I remember working previously. I installed it around February, and based on my recollection, the working combination was:

• QGIS 3.40.4 (Bratislava)
• UMEP 4.1.1
• UMEP for Processing 2.0.35
  I’m not sure which SuPy version is supposed to match this combination. When I tried installing SuPy, it ended up using something like 2024.5.7.dev (if I remember correctly). With this setup, it still doesn’t work, and every time I run SUEWS Simple, a popup appears showing a NoneType error.everytime i run suews simple.

3. I then tried again using supy 2025.11.20 (at QGIS 3.40.13), since 2025.11.20rc1 is not available via pip and I couldn’t find it in the OSGeo shell either. After clicking Run in SUEWS Simple, the following error appears in the log messages:
   2025-12-15T16:53:19 WARNING Traceback (most recent call last): File "C:\Users\Acer\AppData\Roaming\QGIS\QGIS3\profiles\default\python\plugins\UMEP\SuewsSimple\suews_simple.py", line 430, in start_progress with open(self.supylib + '/sample_run/sample_config.yml', 'r') as f: FileNotFoundError: [Errno 2] No such file or directory: 'C:\Users\Acer\AppData\Roaming\Python\Python312\site-packages\supy\sample_run\sample_config.yml'
   I’m not sure whether this error is the reason why the Run button is trying to fetch the sample data instead of using the selected input data.

4. Finally, I tried again using:

• QGIS 3.40.13
• UMEP 4.4.3
• UMEP for Processing 2.2.3
• SuPy 2025.7.9.dev
  With this setup, clicking Run changes the dataset from the sample data to the input data, and then QGIS crashes just like i explained in the main post.

1. You should not use 3.28. That is an old version. You should also install the correct supy-version before you update UMEP.
2. Wrong version again
3. the rc1 version is there. Here is the link: https://pypi.org/project/supy/2025.11.20rc1/
4. This does not work since you need the correct version of supy.

You should use:
supy:2025.11.20rc1
UMEP=4.4.5 (last version in development release.
QGIS>3.40

At this point I’m a bit confused about where the problem really is. Thanks a lot for your help.

[reeveugm]

I’ve already installed Supy version 2025.11.20rc1

and UMEP 4.4.5, as well as UMEP for Processing 2.2.6 from the development release

However, the SUEWS Simple window still shows that it’s using Supy 2025.7.9.dev0

I can click Run, and it freezes for a while, but then QGIS crashes.

[biglimp]

Ok, good.
Does it also crash if you run with the default dataset ("Add settings from test dataset")?

[reeveugm]

Yeah, it didn’t crash when I used the default dataset. So I guess the issue might be with the dataset I was using? I actually remember it working fine with this same dataset before.

[reeveugm]

I tried it again using the default settings and only changed the meteorological forcing input to my own dataset, and it worked fine. However, I found that when I set the "Height of the meteorological forcing data (m)" to 10 m, it crashed—even when using the default dataset.

This setup uses the default settings, with only the forcing input replaced by my own dataset. It runs without any issues.

This setup is identical to the default configuration after clicking “Add settings from test dataset”, except that the “Height of the meteorological forcing data (m)” is changed to 10.0 m. With this change, QGIS crashes.

In my previous work, I used a forcing height of 10 m, and the model ran successfully and produced results.

For reference, here is the forcing dataset I used, in case it is helpful. This dataset was preprocessed to mimic the structure of the default dataset after downloading it from shinyweatherdata.com.

TestData1_Output.txt

[biglimp]

Great that you found the issue. I can now replicate your error. I also ran it outside of QGIS and got the following messages:

>>> import supy as sp
>>> infile = 'c:/temp/kk_suews_simple.yml'
>>> config = sp.data_model.init_config_from_yaml(infile)
>>> df_state_init = config.to_df_state()
>>> grid = df_state_init.index[0]
>>> df_forcing = sp.load_forcing_grid(infile, grid, df_state_init=df_state_init)
>>> df_output, df_state_final = sp.run_supy(df_forcing, df_state_init)
2025-12-16 16:26:01,472 - SuPy - INFO - ====================
2025-12-16 16:26:01,473 - SuPy - INFO - SUEWS version: 2025.11.20rc1
2025-12-16 16:26:01,474 - SuPy - INFO - Simulation period:
2025-12-16 16:26:01,475 - SuPy - INFO -   Start: 2012-01-01 00:05:00
2025-12-16 16:26:01,476 - SuPy - INFO -   End: 2013-01-01 00:00:00
2025-12-16 16:26:01,476 - SuPy - INFO -
2025-12-16 16:26:01,476 - SuPy - INFO - No. of grids: 1
2025-12-16 16:26:01,477 - SuPy - INFO - SUEWS is running in serial mode
 >>> See problems.txt for serious issues in the run <<<
 ERROR! SUEWS run stopped.
 problem: In SUEWS_cal_RoughnessParameters, (z-zd) < 0 m.
 See problems.txt for more info.
STOP Fatal error in SUEWS!

Why this makes QGIS crash, we need to investigate further. What you can do is, either to set a height that is acceptable or find a new forcing dataset. SUEWS is a local model that calculate fluxes in the inertial sub-layer i.e. two-three times the mean building height.

[biglimp]

You can follow the error from the SUEWS-side here: UMEP-dev/SUEWS#1035

[reeveugm]

Alright, I might consider adjusting the height of the meteorological forcing data. Thank you for the clarification.