I decided to get a weather station for the house. Went with a Davis WeatherLink Live and Vantage Vue Wireless Sensor Suite. This is a no-console setup that has a network-attached receiver that collects sensor data and makes it available to cloud servers or mobile apps. It's got an API for accessing the collected data, which I will be using for the plugin.
I already started the plugin, even though I won't have the system installed until next week.