The Leader can reveal at least two days of climate data has been removed from the BoM observation pages during that time.

The BoM initially claimed that Monday morning was the coldest on record with a reading of -8.6, although it has since revealed that reading was almost three degrees off.

An almost identical error was made last month on June 15.

Readings from both June 15 and last Saturday have since been removed, while Monday’s minimum has been corrected.

The Leader questioned the BoM on Monday, weeks after Tamworth Region Weather’s David Farrenden contacted the Bureau in regards to the incorrect readings.

Late on Monday night, BoM spokesperson Daniel Barty confirmed the errors.

“There were a couple of numbers over the weekend identified by forecasters as being questionable, and that cross-check found a mistake that is under investigation at the moment,” Mr Barty said.

“The weather station is being calibrated and put through quality control – we are not sure about the cause of the issue.” 

The BoM also confirmed a record was in fact broken on Saturday morning, with the correct reading of -5.7 degrees the coldest morning since -6.6 was set in July 2011.

“The weather stations auto-update straight to the website, and our cross-check showed a spike we weren’t convinced was correct. The -8.6 was not correct,” Mr Barty said.

“Most of the numbers over the last month are correct, there are just a few outliers that we are investigating. Climate specialists are now looking at the data to find the nature of the problem.”

That team will also process data from nearby stations, and historical data to correlate temperatures for the missing days to calculate averages and “account for the anomaly”.