Hobart has just registered an unprecedented sixth January day at or above 30-degrees, as the city nears the end of what will likely be its hottest calendar month on record.

Today was Hobart's 6th day at or above 30 degrees so far this month, which is a new record for January.

Prior to 2019, Hobart's highest number of 30 degree days during January was five, which has happened on several occasions, most recently in 2012 and as far back as 1887.

The new January record may be increased to seven days on Wednesday, with the mercury forecast to reach a top of 30 degrees in the city. This would also a new record for any month, beating six days from December 1994 and 1897.

This January has been remarkably hot in Hobart and for much of Australia, thanks largely to a late arrival of the monsoon in northwestern Australia and blocking high pressure systems frequently sitting to the east of Australia. The background influence of climate change is also likely to have played a part in this month's record heat.

Unsurprisingly, Hobart's running average maximum temperature during January is well above average. In fact, it's also unprecedented.

As of 9am on Tuesday, the city's average maximum temperature during January was 25.9 degrees, well above the long-term average of 21.7 degrees.

Based on forecast tops of 30 degrees on Wednesday and 19 degrees on Thursday, the city's average maximum temperature at the end of January should be brought down to 25.8 degrees. This would make January Hobart's hottest calendar month on record based on maximum temperatures, with data available back to the late 1800s. The previous record was 25.2 degrees from February, 1895.

A lack of strong cold fronts has also seen a measly 0.4mm of rain reach the city's gauge so far this month, as of 9am on Tuesday. If this remains unchanged until 9am on Thursday, this will also be Hobart's driest January and equal driest calendar month on record.