Hey Daniel Vaughan
I had a quick look at the web app you linked to. I used the developer tools (F12) in my web browser and the network tab of the developers tools to find out where it was getting its data from. I then found this link:
https://severeweather.wmo.int/v2/json/all.json?20200205090805
This appears to contain all the data that you need.
Let me know if you need anymore help!
Thanks,
Ben
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