If you want to know 'how far can you see a manmade sunrise?' pretty damn far in the flatlands.
If you want to know can you outrun the shock wave? Not a chance if it is going to hit you it will wack you hard and fast.
Now having scared the pee water out of you, unless you are close to ground zero, the blast point, chances are good you can survive a simple, single explosion. The more common, transportable nukes are relativily small, compared to the ICBM type, unless it is an air burst the blast will be contained and muffled by the buildings of the city, did I mention avoid big cities?, you should be able to get away from most of the fallout, work your way upwind by getting cross wind from the blast. Most winds in USA blow W-E so go N or S whichever is closer to get away, then head for a remote area and wait for civilization to rebuild.
This should put most of your dreams on the fast track.
TRW