KenC:
Welcome to the WeatherCat Forums. We are glad to have you. Yes, WeatherCat runs fine on Sonoma with a Vantage Vue. I have a different Davis station, but the Vue is supported. I am currently running on macOS Sonoma. You may want to upgrade to the most recent release of Sonoma, which is 14.8.9.
The WeatherCat manual is excellent for walking you through how to set up your Vue, and if you have specific questions you can come back to the forum and someone will answer them.
FYI, you posted this question in the section for iOS clients, which is where you ask questions about using WeatherCat on your iPhone and iPad. If you have followup questions, start a new topic in the WeatherCat General Discussion forum.