When the USPS status says in transit to the next USPS facility it means that the package has been scanned and left the current USPS sorting Facility and is on either a Semi, airplane or whatever it's traveling on to the next USPS sorting facility where it will then likely be handed off to a smaller USPS truck to make it's way to your local Post Office.
When it arrives at your local post office the tracking info should state that it arrived at your post office and is out for delivery.
The USPS tracking info status can stay stuck at in transit to the next USPS facility until it reaches either another USPS sorting facility or until it reaches your local post office to be delivered.