cold front brings dust, storms and heavy rain to SA, NSW, VIC,
|The synoptic chart for 5pm EDST today. A low has formed
on the front over Melbourne while strong warm northerlies cover eastern
NSW and VIC. BoM
A strong cold front moved across SA, TAS and western VIC today, producing
widespread duststorms and thunderstorms in hot northwesterlies ahead of it,
and dropping temperatures 10 to 12 degrees across the south of the country.
A complex frontal zone, with a marked trough leading the colder air by about
300km, crossed the SA coast near Adelaide around 6am. By mid morning, a low
had developed in the frontal zone over western Victoria. The slowly deepening
low passed over Melbourne late afternoon, and was in central Bass Strait by
midnight with a central pressure of 997hPa.
A deep, sharp upper trough accompanied
the front, with a 120km/h NNW jetstream ahead and a 16° temperature difference
across it at 850hPa (about 1.4km).
Duststorms. Strong convection assisted by the upper jet raised
dust to high altitudes ahead of the front, while classic "wall-of-dust" duststorms
SE SA, western VIC, southern NSW and also SW QLD. It was described by a Bureau
of Meteorology spokesman as the most significant dust event in Victoria in
20 years. The worst duststorms
were in the SA and VIC Mallee
the VIC Wimmera where visibility was reduced to less than 100m during
the afternoon by blowing dust. Squally winds gusted to 80km/h over the whole
area, with a peak gust of 96km/h recorded at Naracoorte SA at 3pm.
arrived in Mildura around 11am, reducing official visibility measurements
at the airport
3pm and 200m
Weather station observer Tony Grasso told ABC News that the dust storm turned
the sky red and created some of the worst conditions for visibility ever
were at their worst around 1pm when a squally wind change reduced visibility
the city to around 10m according to press reports, and 20m at the airport.
Said one resident: "Visibility went down to 20 metres; it went like
night here in Mildura. The front had a wind stop in it so as the dust
wall went over it went hushed and you could look up and see the dust blow
over. Then it started blowing again." Another resident said "We
all expect [duststorms] up here. The reason
why we are going on about [this one] is it was just so thick and black. It
was dark red to black dust and it was thick as visibility was less than
20m for about 30
then 100m for 6 hours after that. It was an amazing system because of colour
and thickness, that is why we are going on about it and how everything
is covered with a few millimetres of dust. Trees, grass, everything is brown."
SA, Warracknabeal VIC and Hay NSW all reported severe duststorms with visibility
of 100m or
less around 3pm. The dust area moved across Melbourne during the afternoon,
where the levels of dust in the air were among the highest ever measured
and visibility was reduced to 3km.
Mildura Top Crop officer Daryl Pearl told ABC
News that farmers would be counting the cost of the duststorms for many years.
the wind blew away fragile topsoil and valuable nutrients from paddocks already
suffering from drought, and farmers
would now be looking for rain to settle the dust and return structure to
the soil. But he added that the topsoil would be scattered over a wide area
the storm. "Anywhere from here to New Zealand, we'll top-dress a few paddocks
along the way but we might end up giving something to the land of the long
white cloud...we might turn it a bit orange, I think," he said.
Thunderstorms and rain. Two lines of thunderstorms produced
torrential rain in SE SA and SW VIC during the day. The first developed along
the troughline to the west of the Eyre Peninsula during the early morning and
moved over the Adelaide area around 8am. Gusty winds and brief heavy rain caused
peak hour traffic chaos with traffic lights knocked out and accidents blocking
roads. The SES received 45 calls for help from Noarlunga in the south to Salisbury
in the north as houses were flooded and trees brought down, including one that
brought down powerlines, blocking the Glenelg tram service for most of the
morning. Adelaide Airport recorded a top wind gust of 82km/h at 8.09am.
A second area of storms, packing torrential rain and storm force wind gusts,
accompanied the low that developed on the cold front as it crossed the SE SA
coast and moved into western VIC. The fast-moving storms produced some very
high rainfall rates (see downpours below). Coonawarra
recorded 15.2mm in 6 minutes to 1.54pm, and Mt Gambier airport 14.8mm in 17
minutes to 2.44pm. Robe reported 64mm between 9am and 3pm, the combined total
of the morning and early afternoon storms. The
heavy rain caused some flash flooding of homes in the Southeast, while squally
winds brought down powerlines and trees, and contributed to a collision between
a truck and a utility on the Bordertown to Naracoorte Road, seriously injuring
the utility driver. Stock losses were reported, including over 1,000 sheep
on a property near Penola and more than 150 sheep on another near
As cool upper air combined with
strongly converging winds around the developing low,
explosively as it moved into Victoria's West Coast and Western Plains. Hamilton
airport recorded 32.6mm between 5 and 7pm with wind gusting to 89km/h at
6pm. An unofficial weather station 17km west of Hamilton recorded 86mm between
and 5.30pm, with rainfall rates as high as 223mm/hour and a storm event total
of 110mm. 5cm hail fell early in the storm and flash flooding to 1.5m deep
carried mud through the house at the station. Hamilton
emergency crews received over 30 calls to assist at flooded buildings in
and around the town. Similar
conditions are likely to have occurred over
wide area, with official 24-hour rainfall totals to 9am Thursday including
83.2 at Casterton, 70.2 at Dunkeld and 61.6 at Warrnambool Airport.
The storms produced several new rainfall records (see
also the records section for
Thursday). Robe's 24-hour total to 9am Thursday of
67.6mm beat a previous March record of 56.1mm. What is significant is that
Robe has an extraordinarily long rainfall record of 138 years. The 83.2mm reported
at Casterton Showground was the stations highest fall for any 24-hour to 9am
period since records began in 1956. Press reports indicate some very heavy
unofficial rain measurements along the storm track to the ESE of Robe. The
Kangaroo Inn Area School, 48km ESE of Robe, recorded 112mm for the 24 hours
to 9am Thursday, while a gauge near Penola registered 94mm.
Another area of storms developed ahead of the front to the west of Melbourne
mid-morning, then propagated east and southeast during the afternoon giving
heavy rain to Tasmania's north coast and high winds through Melbourne, eastern
VIC and northern TAS. Melbourne Airport recorded a gust of 91km/h at 8.53am
and Mt Hotham summit recorded 113km/h at 4.30pm. Late in the evening, Cape
Grim, on the northwestern tip of TAS, was reporting gusts to 130km/h at 11pm
and midnight, with sustained speeds around 100km/h indicating that conditions
in Bass Strait would have been far from comfortable. Lightning struck a tram
as the storm passed through Melbourne causing a fire in its roof. Lightning
also started a fire that burned through over 60 hectares near Gembrook in the
For another article on this event, go to Stormplanet.
Overnight minima ahead of the front
in western VIC were exceptionally high for March with most
centres reporting readings more than 10° above normal in the low
to mid 20s. Tarraleah, on the TAS Central Plateaux, reported a low
of 17.5, 12 above.
The monsoonal trough is still marginally
active along the NT coastline, triggering storms that gave
Milingimbi 71mm in 6 hours to 3am and Dum In Mirrie 38mm in 3 hours
to 9pm. Territory Wildlife Park reported 95.5mm for the 24 hours to
Cloncurry Airport QLD reported a wind gust of 121km/h
with a 10-minute average of 80km/h at 2.31pm from a thunderstorm that
dropped only 5mm of rain.