As you might be aware, Carnarvon radar is in the process of being upgraded. Refer:
http://www.bom.gov.au/products/IDR053.loop.shtml#skip
After a month or so of construction etc, it was ready for testing last Wednesday. We shut off the display on the external web pages but kept the data flowing internally so that we could inspect the product. Radars need tuning before they are ready for general use. Unfortunately we did not turn off the contribution from Carnarvon to the national summary and that's what you saw on it - the untuned returns from Carnarvon radar.
Apologies for the inconvenience. We've adjusted our systems now so that the Carnarvon radar image data isn't available externally.
Of course, they would write something like that. Wouldn't they? ;)