To follow up on Desoto's reply with a little more weather nerd added in. Radar can't, and never will, be able to tell you what is happening in real time. Best case scenario it lags reality by 3-5 minutes. That is due to the fact that each radar image is a composite of 4 different radar scans at different elevations. It then has to process that and the computer has to send it out in the readable radar image we are all familiar with. With a tornado on the ground possibly moving 60-70mph, 3-5 minutes can make a big difference.
Also, the further you get from a radar site the higher the beam is due to it being set at a 0.5 degree tilt at the lowest level. That, combined with the curvature of the earth means the beam is steadily getting higher off of the ground. By 80 miles the beam is 7,000ft off the ground. That means it is completely blind to what is happening below that height. For EF-0 and EF-1 tornadoes that can mean that it can be on the ground and causing damage, but the NWS has no way of confirming that because it can't see the debris signature on radar which means the warning is not upgraded. Research has shown people are 75% more likely to take shelter when they know a tornado has been confirmed.
So that is where we come in. We try to position ourselves with a view of the storm to see if it is producing a tornado or not. We can also report back on hail and straight line winds. Additionally, we are often one of the first on the scene after a tornado hits and can assist in search and rescue which I have done twice and why I carry a decent supply of medical supplies.
However, we can't be everywhere at once. That is why our chase team nonprofit wing is working to get a camera network set up on towers across the state so that NWS and local media can see what a storm is producing. It has been an extremely uphill climb with a lot of obstacles but we are starting to make progress. Just yesterday we finally got sites to post some cameras. Now we just have to have the funds to buy them.