For warnings (and other information) from the National Weather Service, the tool is a Weather Alert radio, if you are expecting to monitor radio. My RV radio has a band for this, I think many do now. But maybe not the radios in a pickup truck.
Those of us who live in the middle of the country have learned to watch broadcast TV during a storm. More about that later.
Tornadoes predicted? Not sure of your meaning. NWS does not make predictions of tornadoes, but other meteorological sources do try to predict the future locations of known tornadoes, squall lines, and individual storm cells.
When weather (existence of heat energy sources and air instability, combined with moving fronts) is suitable for generating tornadoes (or severe thunderstorms), the NWS will issue a WATCH.
Sometimes there will be a probability associated with that watch. For the storm system last Friday, the WATCH area extended from the southwest corner of Oklahoma to Chicago, and was about 400 miles wide along that line. At least 360,000 square miles of Watch area.
The class of watch was "100% probability of tornadoes being generated somewhere in this area." But the area hit by tornadoes was less than 100th of a percent of the total watch area, so by that measure, probability on the order of 0.0001 for a tornado in any given place. That's about as far as we can go today, predicting tornadoes.
A severe thunderstorm or tornado WARNING is not a prediction. It is a NOTICE that the phenomenon is verified to be actually present, RIGHT NOW, in a particular place.
There is nothing between a WATCH (a forecast) and a WARNING (a sighting) from the NWS. Nothing that serves as a prediction.
The NWS is set up to issue watches and warnings by county. That's not much granularity, where we have counties larger than some eastern states. You should be familiar with that in California, consider the size of Riverside or San Bernardino counties.
Predictions come from elsewhere, if local TV stations have set themselves up to perform that service. They don't predict formation of storms, but they do predict paths of known storms. The source is TV.
Our TV broadcast stations have teams of meteorologists monitoring radars: NWS, their own, and each others'. They are watching storm cell tracks, to predict forward paths of storm movement, speed and direction, arrival times at each community in the path of the storm cell. They are watching rainwater velocities inside the cells, to pick up rotation. The guys an the ground are watching for wall clouds and funnels, reporting existence and movement. They are coordinating their movements with each other, directed by the guys with the radar.
So last Friday, my county was under Tornado Watch from 2 PM to Midnight, and Thunderstorm Watch from 2 PM to 7 AM the next day. It came under Thunderstorm Warning about 5 PM when the first squall lines started rolling through, and continued to have extensions or new Thunderstorm Warnings until about 4 AM.
The county came under Tornado Warning twice during the evening, from 5:45 to 6:45, and a second later tornado approaching a different part of the county 40 miles away extended the Warning for the whole county until 8:15.
On TV, however, I could watch each storm cell approaching from the west, and know whether or not the cell was generating a tornado. I knew the first tornado was crossing the county 16 miles north of my home. I knew the second tornado was crossing the county 8 miles south of my home. I stayed in my storm shelter, TV on, watching each successive wave of storm cells pop up and move across, until we got to the end of the Tornado Watch around mid-night, when the NWS decided that the bodies of unstable air left behind the storm front no longer had sufficient energy to produce tornadic storms.
The TV stations go in this mode not when watches are issued, but when storms first start forming. If it looks really bad, they will stay in full time storm tracking mode until the danger is beyond the TV station's market area. Here, the storms are our news and our entertainment. Reality TV, but without the semi-amateur actors and scripted storylines.
Most of our TV stations have smartphone apps to forward NWS notices as issued, and the higher granularity, more on-time information as it is broadcast, using location services from the phone. These are not so useful traveling, because they are station-specific.
So an least for the really storm intense parts of Tornado Alley (some definitions make that everything between the Rockies and Appalachians), that's how the locals do it. Keep the weather radio on for NWS notices, watch the weather story on TV, real time as it unfolds.
FWIW, for two years I lived in the real Tornado Alley, central Florida. That was long before storm tracking radars that could pick up rotation or work through the different intensity areas inside thunderstorms. We were under Tornado Watch almost half the days for eight months of the year, sometimes from before noon, until almost time to get up in the morning.
Didn't have weather alert radios then in Florida, or the present emergency broadcast system on TV, but information came through local radio and TV stations, which all had live operators and manned newsrooms rather than today's radio station robots. While it was still daylight, we watched the skies. The weather forecasters in the control tower also watched the skies. I saw more tornadoes, two years in central Florida, than I've seen 33 years living in Oklahoma. Partly because we have fewer tornadoes in daylight hours than does Florida, but also because there I was out watching for them to form, here I am inside, letting the TV weather guys do that job for me.
