Set oven rack about 6 inches from the heat source and preheat the oven's broiler. Line a baking sheet with aluminum foil.
Place poblano and serrano chile peppers cut-side down on the lined baking sheet.
Roast under the preheated broiler until the skin of the peppers has blackened and blistered, 5 to 8 minutes. Place blackened peppers into a bowl and tightly seal with plastic wrap. Allow peppers to steam as they cool, about 20 minutes. Remove and discard skins. Finely chop the flesh.
Bring a large pot of water to a boil. Add scallops; cook for 1 minute. Drain and transfer to a glass or ceramic bowl.
Pour lime juice over the scallops. Stir in roasted peppers, tomatoes, onion, cilantro, salt, and black pepper. Cover with plastic wrap and refrigerate ceviche until flavors combine and scallops are opaque, about 2 hours.
Spoon equal amounts of ceviche into 6 martini or margarita glasses to serve.
