I wouldn't be in any big rush to do anything at the moment. JM's can respond to drought stress in a number of ways and early defoliation is certainly one. What appears to be deadwood may not be as bad as you think and I'd wait until spring or at least bud swell before I did anything major. Deadwood will be very obvious at that point - a dead, dry looking grey and with no sign of healthy buds - and can be removed at any time.

Repost with photos in spring and you can get some better direction on how to shape the tree at that time, given what the actual status of growth is compared to what may be truly dead.

And I guess we learned that JM's, even in the PNW, are not the slightest bit drough tolerant, didn't we :-))

Yessiirreee, we did!! What with 2 large rhodys, 8 azaleas, and a veggie garden, it became a case of "What? You, again?!!"
Thanks, I'll be back in the spring.