leaves on branches dying and curling
Although Ma has been very dry we've never had trouble before with our weeping cherry. Age is about 30-35 years, 14 inches across , 25' high. As you can see not all the branches are brown, leaves die, curl and look and feel like dried tobacco but they do not crumble. If wet they feel leathery and supple. Some moth damage but not much and green leaves look OK . The big brown section is all on one main branch but there are other small outbreaks on the tree as well
Cherry and plum trees are showing a lot of this type of damage this year, so your tree is not alone. It is due to the stress of the warm winter, then freezing temperature drops. The trees did not receive the normal weather pattern of going into dormancy, resting, they coming out of it slowly. The stress tree are then more likely to be attacked by disease and insects.
As for your tree, check to see if the bark is damaged anywhere by boring insects. And look for canker spots on bark indicating a disease. Prune back any obviously dead branches that snap when bent. Cut back to live tissue.
You can take a sample to your local Master Gardener office or Extension Center for them to examine the piece under a microscope.