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There is a good app called WeatherMate. it features interactive weather maps experience which contain numerous map overlays containing radar, satellite, severe weather alert, weather stations, weather fronts, temperature gradient and a number of other imageries. Then, the travel planner feature, comprehensive weather archives, screen sharing, weather announcement and NOAA weather radio are sufficient to fulfill your hunger for weather information. try it.
 
You should check out Forecast Bar. I was looking for the same thing as you and really like it. They've got both iOS and macOS versions, both with the same detailed widget, and even a tvOS version too. And yes it syncs via iCloud across everything.
 
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