Here in Washington state we still have time to have the bees raise an emergency queen (or add a queen if you can source one).
You need to figure out if they are truly queenless. If you have another hive you could take a frame with eggs and place it into the hive in question. If they are queenless they will raise an emergency cell; if they are not they will feed and cap the brood. If the population is low you can put a frame or 2 of capped brood from another hive to give the population a bump in order to give them more time to raise a queen. You have many options but you need to figure out with fair certainty that they are queenless as the options change with/without a queen.
You need to figure out if they are truly queenless. If you have another hive you could take a frame with eggs and place it into the hive in question. If they are queenless they will raise an emergency cell; if they are not they will feed and cap the brood. If the population is low you can put a frame or 2 of capped brood from another hive to give the population a bump in order to give them more time to raise a queen. You have many options but you need to figure out with fair certainty that they are queenless as the options change with/without a queen.