A change was released this week which allows users to self-address this issue. If a Smart Lighting Automation that uses sunrise/sunset is created or saved in the new app and you do not have the Weather Station SmartApp installed, it will be installed automatically under the Smart Lighting automation. If you already have sunrise/sunset automations, you should be able to open and save an automation without making a change and see Weather Station installed.
You can verify it was successful in the IDE by looking for Weather Station in your SmartApps list under Smart Lighting:
