1. Heat oven to 450 degrees F.
2. Place potatoes in a large pot and cover with cold water. Bring to a boil. Lower heat and simmer 20 minutes until potatoes are just cooked. Add asparagus and cook for an additional 3 to 4 minutes or until asparagus is tender. Drain; cut potatoes in quarters. Meanwhile, in a medium-size bowl, whisk together brown sugar, vinegar, lemon juice, lime juice, mustard, garlic salt and black pepper.
3. Place salmon in a glass baking dish. Brush 1/4 cup of the sugar-vinegar mixture over the salmon; set remaining mixture aside. Marinate salmon at room temperature for 10 minutes. Bake in 450 degrees F oven for 15 to 18 minutes, or until fish flakes easily.
4. Place warm potatoes and asparagus in a large bowl. Whisk olive oil into remaining sugarvinegar mixture. Gently toss with the potatoes and asparagus. Fold in tomatoes.
5. Serve potato salad warm or at room temperature with the salmon.