36
BAMOS
Dec 2018
Charts of the Past
with Blair Trewin
19 December 1995
A weak low formed southwest of Western Australia on the 15th
and moved slowly eastwards across the Great Australian Bight.
It remained relatively weak until the 18th, when it intensified
rapidly west of Tasmania. It intensified further while crossing
Tasmania on the 19th, reaching a central pressure below
984 hPa off the East Coast that morning. It then moved slowly
east across the Tasman whilst weakening gradually. the 20th was part of a 10-day run below 20 °C from the 19th
to the 28th, the second-longest on record for summer, whilst
Hobart’s four consecutive days below 15 °C from the 18th to the
21st was the longest such summer run since 1964. The cool air
reached as far north as central New South Wales, where Oberon
had a maximum of 9.4 °C on the 19th, and snow fell at higher
elevations on the Alps.
Although the core of the low was relatively small, the overall
size of the circulation was exceptionally large, and pushed a
southerly flow deep into the tropics. Hot air had been building
up in inland Queensland, with 45 °C at Birdsville on both the
17th and the 18th, and temperatures near 45 °C also extending
to Isisford and Longreach on the 18th. The south to southwest
flow brought this hot air to the northern tropical coast in the
following days : Cairns Airport reached 40.5 °C on the 20th,
its highest temperature on record prior to 2018, and also
reached 39.9 °C on both the 19th and 21st, whilst Townsville
also exceeded 40 °C on both the 20th and 21st. The highest
temperature in coastal regions was 43.4 °C at Ingham on the
20th, an equal record for the site. With spring rainfall in the
region having been generally average to above average, no
significant fires were reported. There was also significant weather in northwestern Australia,
where tropical cyclone Gertie made landfall as a category 3
system near Mandora on the morning of the 20th. Mandora
recorded a wind gust of 145 km/h and 161.8 mm of rain, but
only minor damage was reported. The remnant low went on to
track from west to east across the continent, bringing locally
heavy rains, including 80 mm at Marla, in the far north of South
Australia, on the 22nd. There was also severe thunderstorm
activity further south in Western Australia on the 19th, including
a suspected micro-burst which brought down high-tension
power lines 60 km west of Kalgoorlie.
On the southern side of the low, very heavy rainfall fell in eastern
Tasmania. Numerous sites on the East Coast and adjacent
highlands exceeded 100 mm for the 24 hours ending at 9 a.m.
on the 19th. Mount Wellington received 202 mm, followed by a
further 79 mm on the 20th, by which time the rain had shifted
more to the south with falls above 50 mm in areas south of
Hobart. Hobart itself received 72.0 mm on the 19th, its second-
wettest December day on record, and 106 mm across the two
days. Flash flooding occurred in Hobart suburbs and along the
East Coast, and one fisherman was lost in high winds off Maria
Island. Synoptic chart for 0000 UTC, 19 December 1995
The rain was less significant in Victoria with generally light falls
in the south, although an area of heavy rain occurred east of
Melbourne in moist southwest flow, with 127.6 mm in two days
at Warburton East and two-day totals near or above 100 mm
at a number of other sites in the Warburton and Dandenongs
area (compared with only 7.2 mm in Melbourne). In New South
Wales rainfall totals were only light, and there was a bushfire
near Sussex Inlet in dry westerly winds.
It was very cool in southeastern Australia, in what was a very
cool December (including Melbourne’s lowest December mean
maximum on record). Melbourne’s maximum of 16.0 °C on