Thunderstorm
noun
A thunder rain is a rain that's coming with thunder. For all intents and purposes, if you see this, you'll think thunderstorm.
The reading is the on'yomi readings. For 雨, you learned it with 雨天. So you should be able to put them together!
今朝の強烈な雷雨で停電になったので、今はインターネットが使えません。
The severe thunderstorm this morning caused a power outage, so I can’t use the internet right now.
An update is needed before you can continue but you have more than one WaniKani tab open.
Finish up what ever you are doing on the other tab(s), then close them to continue.
The update will complete automatically once the other tab(s) are closed.