For extreme weather watchers, Melbourne has just delivered a December to remember.

If today's forecast maximum of 28 is correct, or near enough, this month will go down as the city's hottest December since 1873.

And if you've had trouble sleeping, here's why: for overnight minimum temperatures, it has been the hottest ever.

The city was also much wetter than usual thanks to the month's other extreme-weather offering - the "once-in-a-century" downpour that flooded whole suburbs.

Yesterday's maximum of 40.3 at 3.53pm was five degrees above the forecast and catapulted 2003 from fourth place to second in the list of the hottest Decembers.

The average maximum for the month has been 27.2 - more than three degrees above the long-term December average of 24 and just below the 27.3 record attained 130 years ago. Victoria as a whole was about two degrees warmer than average.

But it was at night that Melburnians really felt the heat. "Melbourne's average minimum temperature for December at 15.8 degrees is the highest on record," said Ken Dickinson, senior forecaster at the Bureau of Meteorology. The minimum forecast for this morning was 16 degrees - high enough to secure the record ahead of the previous record of 15.5 in December, 1994.

Unusually, Melbourne's scorching heat yesterday matched traditional hot spots like Mildura. The state's highest maximum of 42 was recorded just outside Melbourne at Avalon Airport.

Geelong topped Melbourne with 41.

December was wet as well as warm for Melbourne, with rainfall over 20 per cent higher than the average.

Overall, 2003 was slightly warmer than usual for Victoria, with temperatures about half a degree above average. Rainfall was average, but drought continued in Gippsland and central Victoria, with Melbourne receiving only three-quarters of its normal rainfall. Horsham recorded Victoria's top temperature for 2003, with 46 degrees on January 25. Mt Hotham recorded the coldest on August 20: minus 9.3.

Melbourne's top of 44.1 degrees, also recorded on January 25, was the fourth highest temperature recorded in the city since records began in 1855. It was the hottest day since January 13, 1939 - Black Friday - when the mercury reached 45.6.

More than 80 fires flared across that state in what a Country Fire Authority spokesman said could be a sign of things to come. Two of the outbreaks are believed to have been sparked by farm harvesters.