Scraping Web Data

What is the best/good way to scrape data from a web site and make it available as a tag in the system? My particular application is importing data from a weather station system that does not have any kind of OPC/Modbus feature. It is designed to either display it locally on a PC with a proprietary application, or to export the data to the cloud where users can login and view their local stations data. What I would like to do is have the data available as OPC tags for alarming/etc.

Write the scraping logic in a timer script that periodically updates a memory tag.