Summer pruning keeps the stored energy balanced. As is, whatever was there (catching sunlight) has now stored its energy in the roots. Lop off any amount of the tree and that ‘extra energy’ will pop up as water-suckers.
But Pruning in winter works. I’ve also heard it should be dry for a few days when - and shortly after pruning a cherry tree. If it’s not a big project and you know you’ll have time closer to… March, it might be best to put it off until then.
I’ve not had good luck with cherries, but have wild trees flourishing in the woods next door. I do suspect fewer cuts are better. There have been cherry trees in the Willamette Valley for well over a century, most do just fine.
PS, welcome to our Forum 
I prune in summer after harvest. They're not as bad as peaches, plums, apricots etc. but I think you want to prune when it is dry. My Northstar pie cherry gets bad bacterial infection. Leaving it open to disease in the rain is not good. We often get long high pressure systems like right now that last for 5-7 days in Jan, February, or March, and during one of those would be good. They will overgrow and produce too many branches, that will increase disease if you don't prune them enough.
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