In recent years, the emphasis in meteorology has been to gain "lead time" for tornado warnings (i.e., issue the warnings sooner relative to the storm's arrival time). The U.S. average now is around 14 minutes. In the devastating Alabama tornadoes on April 27th, the average lead time was 24 minutes. In Joplin, the lead time was 19 minutes.
It is an important question because there will always be a tradeoff between accuracy and lead time, i.e., tornado warnings with one hour of lead time (given today's science) will be inaccurate most of the time whereas 1 minute lead time (see below) will be extremely accurate.
AccuWeather decided to ask, via its Facebook page, how much "lead time" readers wanted. Here are the results:
I believe that the bigger problem is false alarms and would rather see meteorology focus on that issue rather than extending lead time further.