Not always. There was a significant stretch of northern Shelby County, AL where the 3/25/11 "Eagle Point" tornado wasn't that obvious in the radar data because of close proximity to the radar, even when it was doing surveyed EF2-EF3 damage. There are other cases. If anything, very close proximity to the radar could make a signature sometimes hard to spot because of the inherent noise around the radar. However, now that we are getting the storm a little farther removed from the radar so that you can see the storm structure on reflectivity and it has the look that the RFD has surged forward to possibly cut off the circulation, I'd agree that there likely isn't a significant tornado ongoing and very possibly wasn't for the last several minutes the emergency was in place. But don't always think close proximity to a radar will always allow a tornado signature to be obvious. There are more than isolated instances where you'd get into life-threatening trouble thinking that.
They dropped the emergency.