You can turn moving storms off through Stormforge's Custom world settings. The control is in the same editor as combat difficulty and the death penalty.
Using Config Editor
- Stop the server and open Configuration Files in TCAdmin.
- Click Config Editor beside
settings.json. - Set World Preset to Custom, then untick Moving Storms. Check the other Custom options before saving, including the combat difficulty and death penalty.

- Click Save & Exit, then start the server.
To enable moving storms again, tick the same box and save with the server stopped. The checkbox writes Off or Normal to worldSettings.movingStormsDifficulty in settings.json.
Using Text Editor
With the server stopped, open Configuration Files and choose Text Editor beside settings.json. Edit these existing entries inside worldSettings:
"worldPreset": "Custom",
"movingStormsDifficulty": "Off"
Use Normal instead of Off to enable moving storms. Keep the other world settings, click Save & Exit and start the server.