Cedar tree browning and dropping leaves
There are many possible causes for browning leaves (it's a like a cough in people... it's a symptom with many possible causes). Cedars can be tricky to keep healthy due to sensitive requirements in soil and vulnerability to desiccation above ground. I'll attach a fact-sheet that discusses several possible issues and how to deal with them (https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/agriculture-and-seafood/animal-and-crops/plant-health/dying-cedar-hedges.pdf). Since it could be a combination of several factors over time (weather last winter, soil changes, age of plants, possible insects etc...), it would be a good idea to have someone local look at the situation on site to get a fuller picture.