* Barring any unforeseen circumstances, the concert will go on as scheduled. (meaning: unless something unexpected happens)
* We're planning a picnic tomorrow, barring rain. (meaning: unless it rains)
* Barring a miracle, our team is unlikely to win the championship. (meaning: unless something extraordinary happens)
* The hikers were warned to stay on the trail, barring any emergencies. (meaning: except in cases of emergency)
* He's a strong contender for the job, barring any unexpected revelations about his past. (meaning: unless something negative is discovered about him)
As you can see, "barring" is often used to introduce a condition that would prevent something from happening. It implies that something is likely to happen, unless the stated condition occurs.