That's normal. Pressure Canning is bringing the temperature of its contents to over 240°F. Normal boiling temperature is 212°F so those superheated jars and contents will take awhile to cool down even to the boiling temperature.
Because of the danger of temperature shock that could shatter jars, you should wait 10 minutes after the canner comes down to normal pressure and the regulator is removed, but before the lid is removed. This allows the inside to cool down better before being exposed the normal air and possible drafts.
Support bacteria. It's the only culture some people have.