Like most of the midwest, if you don't like the weather in Lincoln, all you have to do is wait a minute, and it will change.  The summers are warm and humid.  The winters cold, and really cold.  The best time to go is spring or fall - either is considered "football season." 

Best weather though is September-October and March-April.  As it turns out, this is also "tornado season."  And the first smell of fireplaces burning as the leaves turn and the weather gets cool enough you need a sweater.