How can remote-sensing satellites people stay safe from massive fires?

Remote-sensing satellites would be able to help people stay safe from massive fires through them detecting it from the orbit and sending the data to the people below. The people would be able to warn other people of the massive fires currently happening nearby, thus resulting to zero casualties. Though that might be the case, satellites might only be able to detect massive fires to the extent that the damage has already been done. It can be contained, but it would be much better if it would detect a certain size of fire and consider it as dangerous. Massive fires, on personal knowledge, would come close to burning neighbourhoods and those that occur in forests.