Sydney is likely to sweat through its hottest pair of days in 80 years and the hottest outside of the height of summer.

Sydney is forecast to reach 39°C on both Saturday and Sunday, a feat that has never been done in any month other than January in its 162 year history.

Images: Temperatures expected on Saturday (top) and Sunday (bottom)

The two other periods that may be hotter this weekend were in 1960 (4-days above 39°C between 25th and 28th January), and in 1946 (39.0°C on 4th and 39.8°C on 5th January). Consequently, this weekend could be the third hottest pair of days on record for Sydney.

It is even possible that both days could crack the 40-degree mark, something that has only happened once before (41.1°C on 26th and 42.4°C on 27th January 1960).

In addition to the draining daytime temperatures, the overnight ‘low’ could set records in its own right.

Sydney is forecast to stay above 24°C overnight, with western suburbs keeping above 26°C. Sydney’s springtime record hot minimum temperature is 24.8°C, set on 14th November 1967. Tonight could very well challenge that record, as well as smashing the records set out west. 

Sydney has only reached this hot milestone a handful of times, not because the airmass wasn’t hot enough, but because its coastal location usually receives a seabreeze. This weekend, westerly winds will be strong enough to considerably delay a seabreeze on Saturday, and entirely prevent one on Sunday.

Sydney’s sweltering weekend should come to an end in the late afternoon on Sunday, as a southerly buster roars up the coast, likely bringing a rapid temperature drop of more than 15 degrees in the first hour.