Rain relief on it’s way for NSW
The burst of late-season heat that seared south-eastern Australia over the weekend will give way to days of heavy showers for Sydney with bigger falls forecast for coastal regions to the north.
The falls, though, will likely be minimal over bushfire-hit parts of the NSW South Coast where a forest fire danger index reached a record high for March, according to the Bureau of Meteorology.
Sydney on Monday fell shy of hitting three consecutive March days of 30 degrees – which would have been the first such trio in the month since 1902 – with a top of 28.4 degrees.
A wind shift from the north-west that had brought warm air from central Australia to an easterly flow put a cap of temperatures.
Tuesday’s forecast top of 27 degrees will make way for three days of about 23-24 degrees, with rainfall totals mounting as a low-pressure trough moves in.
“At this stage, it looks like [the trough] will have the biggest impact on the central coast and possibly even further north,” said Rose Barr, a duty forecaster at the bureau. “It is dependent on where this coastal feature develops.”
Newcastle may be among the wettest locations, with 10-20 millimetres forecast for Tuesday and 90-120 millimetres on Wednesday. Thursday may also be wet, with 20-40 millimetres more possible.
The heavier falls are likely to come from thunderstorms developing within the system, Ms Barr said.
Tathra, where 69 homes were destroyed and 39 damaged in Sunday’s fires, won’t get much rain in the system, with Thursday’s 2-8 millimetres the most for any of the coming days.
The system is not likely to take on the form of an east coast low, Ms Barr said, noting the absence of upper-level conditions conducive to the more extreme rains and wind.
Temperatures should begin to climb again by the weekend, with tops in Sydney of 26 and 30 degrees currently forecast for Saturday and Sunday, respectively.
It’s unlikely Sydney will see a repeat of last weekend’s heat, which included its hottest day this late in the season – 39.4 degrees on Sunday – since 1940. Richmond had its warmest day this far into autumn on record.
The heatwave included a range of record maximum March temperatures for towns on the NSW South Coast, included 38.9 degrees at Moruya Airport and 38.1 degrees at Merimbula, the Bureau of Meteorology said.
According to Blair Trewin, the bureau’s senior climatologist, the forest fire danger index “was the highest on record for March for most areas of the NSW South Coast from Nowra southwards, as well as far east Gippsland and parts of the Monaro” such as Bombala.
On Saturday, every eastern capital – Adelaide, Hobart, Melbourne, Sydney, Brisbane, and Canberra – topped 30 degrees. That was the first time in March in 53 years, and the latest in the season since records started including Canberra 80 years ago, Brett Dutschke, senior meteorologist at Weatherzone, said.