Sea surface temperatures just east of Bass Strait are abnormally well above normal for this time of year being nearly four degrees above normal.
With this low passing near Gabo Island this could result in rainfalls near 100 millimetres in the next few days and a wet start to December. It may not be until well into the second week of December before we get very hot days of 38 degrees and then during the Christmas period very hot days of near 40 degrees.
Despite heavy rain this month at many places in Queensland, it has been very dry in Cairns - only five millimetres have fallen against a November average of 95 millimetres. The four drier Novembers were in 1913, 1922, 1990 and 2019. All of these certainly led to a hotter than normal summer in Victoria.
Humid conditions with thunderstorms
During the past week many regions were subject to warm to hot and humid conditions with scattered thunderstorms. Rainfalls were very variable with the odd very heavy showers. Heavy rainfalls were recorded in the Wimmera and also in south-east of South Australia where Naracoorte recorded a two day total of 118 millimetres, the heaviest for November in 155 years of records. The previous wettest November was 113.5 millimetres in 1887. Other very wet Novembers of more than 85 millimetres at Naracoorte were in 1947, 1952, 1964, 1979 and 1992. Only one of these, 1992, occurred during an El Nino situation and for that alone it was much wetter than usual in our regions from May 1992 right through to December 1993.
Quite a few places from Victoria right up to outback Queensland have recorded over 100 millimetres for November, but many other places have recorded less than 25 millimetres this month. Forbes for example has recorded only 10 millimetres. Coonabarabran has recorded 146 millimetres so far this month, making this the third successive November exceeding 100 millimetres - 159 in November 2022 and 254 in November 2021. It was almost equally wet during the three successive very wet Novembers of 1999 to 2001 in Coonabarabran.
It has been very dry in Coonabarabran since last April and there was a very similar rainfall pattern in 1937 when 130 millimetres fell in November. This was the only other similar rainfall pattern which did occur in Coonabarabran in the last 144 years. The summer of 1937-38 was warmer than normal with the 1938 autumn being one of the warmest and driest on record.
Dry period in previous months
At Moree 109.6 millimetres was recorded so far this month. This followed a very dry July to October period of only 35 millimetres. A very similar rainfall pattern happened at Moree in 1941 when 145.6 millimetres fell in November that year. The summer of 1941-42 was notably very hot in our regions, up to 43 degrees during early January. Many other places recorded above average rainfalls in both February and March of 1942.
Further north into Queensland, St George has recorded 118 millimetres so far this month and this followed a very dry period from February right through to October. The rainfall records for St George show there was almost an identical rainfall pattern from the February to October period in 1895. Both December 1895 and January 1896 were extremely hot months in South Australia, Victoria, NSW and Queensland. Heavy rain arrived in February 1896.