Where is the Dark Sky weather app for iPhone?

The Dark Sky weather app has been officially discontinued by Apple. Dark Sky is not available in the App Store as of December 31, 2022.
Apple acquired Dark Sky in March 2020 and has integrated many Dark Sky features into its own Weather app on the iPhone, iPad, and Mac. Apple Weather launched with 10-day hourly forecasts, hyper-local precipitation forecasts, and high-resolution maps in iOS 16.