Do jars have to be covered with water when canning?

Chef's answer
Once all the jars have lids and rings, lower them into your canning pot. Make sure the jars are fully submerged and are covered with about an inch of water (you need that much to ensure that they won't become exposed during boiling). ... You don't want the water to be rolling when you reach in with your jar lifter.
Frequently asked Questions 🎓
Stack the jars into your DRY water bath. Place a weight (or weights) on the jars to keep them from floating. Fill the water bath with HOT tap water. Until the jars are covered and the water is at an acceptable level for your sous vide.
Place the jars in a heat-safe container large enough to hold all the jars and a sous vide circulator, and yes it's okay to stack the jars (I used an 8-quart stockpot in the photo above). Also, place the cooking vessel on a heat-proof surface away from children or pets.
Sous vide cooking doesn't always require plastic. Glass canning jars are also a fine cooking vessel, especially with recipes that require a lot of liquid or a high cooking temperature.
Once all the jars have lids and rings, lower them into your canning pot. Make sure the jars are fully submerged and are covered with about an inch of water (you need that much to ensure that they won't become exposed during boiling). ... You don't want the water to be rolling when you reach in with your jar lifter.
Again, a wide-mouth mason jar is your best best when it comes to freezing anything, especially when it comes to soups and stews. This is my favorite Wide Mouth Funnel for filling mason jars to freeze.
While turning jars upside down can produce a seal (because the heat of the product coming in contact with the lid causes the sealing compound to soften and then seal as the jars cool), the seal tends to be weaker than one produced by a short boiling water process (you should never be able to remove the lid from a home ...
Wash the jars, lids and bands in hot, soapy water.
A few more cooking questions 📍