Yeah just look at '97....that was a blue bomb (albeit historic and extreme) surrounded by 60F tshirt weather....there wasn't anything large scale in the hemispheric long wave pattern that drove that to happen like, say, April 1982 when we were in the midst of a "February in April" type pattern with -10 to -15C sitting over us on the eve of the event with the entire northenr half of the CONUS well below 0C at 850.
In '97 I was hitting golf balls at the driving range the day before in short sleeves and even overheard a couple dudes laughing about the 6-10" forecast for the next day not believing it....they were right to be skeptical, just in the wrong direction, haha. But as you said....perfectly timed bowling ball that went nuts.