For the salad: Bring a large saucepan of salted water to a boil over high heat. Add the snap peas and cook until vibrant green, about 1 to 2 minutes. Drain and transfer to a bowl of iced water to cool, about 2 minutes. Drain and add to a salad bowl. Stir in the cucumbers, tomatoes and dill.
For the dressing: In a small bowl, whisk together the lemon juice, olive oil and lemon zest until smooth. Season with salt and pepper, to taste.
Pour the dressing over the salad and toss until coated.
Cook's Note: As an alternative to boiling, the snap peas can be lightly steamed for 2 minutes.