Adelaide came close to registering its coldest January day on record on Sunday.

The temperature at Adelaide's West Terrace weather station only reached 16.6 degrees on Sunday, thanks to a blanket of cloud streaming down from a low pressure system off Australia's northwest coast. This is about 13 degrees below average for this time of year and lower than the city's lowest January maximum temperature on record, which was 17.1 degrees in 1970.

Image: A stagnant northwest cloud band over Adelaide kept the city's maximum temperature well below average on Sunday.

However, official maximum temperatures in Australia are measured as the highest temperature during the 24 hours to 9am each day. 

Just before 9am on Tuesday, the temperature at Adelaide's West Terrace site reached 17.8 degrees, which became the official maximum temperature for the previous 24 hour period.

Adelaide's West Terrace weather station was not recording observations between 1979 and 2018, so it's not possible to know if this site had a January maximum temperature below 17.8 degrees in recent decades. The last observed January maximum temperature lower than this was 17.5 degrees in 1975.

Another Adelaide weather station at Kent Town registered a maximum temperature of 18.9 degrees during the 24 hours to 9am on Tuesday. This was their lowest January maximum in 13 years.

According to the Bureau of Meteorology, a number of other locations in South Australia registered their lowest January maximum temperatures on record during the 24 hours to 9am on Monday.

Updated temperature record table from today's earlier tweets to fix incorrect dates.https://t.co/oSBBN3TV2m pic.twitter.com/ZmbyZu9O4m

— Bureau of Meteorology, South Australia (@BOM_SA) January 6, 2020