Not to nitpick Gene, but why do you need to take away any rain that runs off quickly? That’s all built into summer climo. You’ve (we’ve) always had short duration intense convective rains in the summer since the dawn of time. It counts just as much.
No where in the annual precip of New England does it say short duration heavy rains need to be removed… the annual precipitation totals build plenty of that in.
I’ve always found that reasoning odd but it’s not just you, it does come up around here in the forums a lot in summer… when folks are like I got X inches of rain this past month but most of it doesn’t really count because it fell quickly and ran off. I know its a reference to not feeling like the vegetation got watered, but the vegetation has been dealing with convective rains for centuries here.