Need strategy for using WeatherKit in the background

I asked a similar question a while back: https://developer.apple.com/forums/thread/730946

Since then I have a new Mac and new iPhone and so I now have the hardware to actually play with WeatherKit. I've worked my way past all the entitlements stuff and have been able to use and expand on online examples. Cool.

Trouble is, nearly every example you can find uses code designed to update the UI as fresh weather data is fetched. My app currently uses background URL fetches to obtain weather data, make some calculations and take appropriate actions, all in the background. Updating the UI was a separate challenge.

So which asynchronous tool is the right one for this? How can I quickly update my existing code to call WeatherKit instead of going to a weather site for a download?

I currently use something like a download task session:

 let weatherTask = session.downloadTask (with: URL(string: urlString)!)
    weatherTask.taskDescription = "weather"
     weatherTask.resume()

or a dataTask session:

var request = URLRequest(url: url)
 request.httpMethod = "GET"
 request.addValue("text/html", forHTTPHeaderField: "Content-Type")
let taskWeatherPOP = URLSession.shared.dataTask(with: request) { (data, response, error) in
 if error != nil {
        print("Error is \(String(describing: error))")
                                }
   if let POPData = data,
        let report = String(data: POPData, encoding: String.Encoding.utf8) {
if weatherReportPOP.contains("ServiceUnavailable") {
   print("A Weather POP report error")
      } else {
        weatherReportPOP = report
         
       }  // Close the IF service unavailable
    } // Closes the IF weather data is not nil
}  //  Close Task Weather
  taskWeatherPOP.resume()