Combine first 3 ingredients in a large nonstick skillet; stir well. Bring mixture to a boil over medium heat. Reduce to low, add salmon. Simmer 8 minutes or until fish flakes easily when tested with a fork.
While salmon cooks, combine yogurt, cucumber, dillweed, and salt; stir well.
Gently transfer salmon to a serving platter, using two spatulas; spoon cucumber sauce evenly over salmon.