Zest the lemons using a microplane. Squeeze the juice through a strainer. Reserve 2 Tbsp. of zest and ½ c. of juice.
Slice the avocado around the pit lengthwise. Remove the pit and discard. Scoop the avocado from the skin with a large kitchen spoon. Dice into ¼” pieces.
Place in a stainless steel mixing bowl. Whisk the batches together. Adjust desired consistency with cold water, if necessary. Place in a storage container. Refrigerate until needed.