Cedars and weeping false cypress struggling

I am in Toronto, and for the last few years I have noticed that mature cedars in my area, inducing the beloved two in my back yard are becoming quite spare. The same is happening t0 the 17 year old weeping false cypress we have which was thriving until last year. I am wondering if this has to do with the odd weather we have been having - very dry summers and rapid freeze/thaw changes during the winter. Have other people noticed this trend, and is there anything I can do beyond watering and feeding? Thanks in advance for any feedback.

 

What species of cedar, Atlas, Lebanon or Deodar? Can you post some photos?

 

The two mature cedars are thuja occidentalist - Easter White Cedars, Michael. I have noticed others in the area are not faring well either. I will try to post pics. Thanks for the reply.