|Early morning storms over the Central Tablelands and Sydney area initiated by a weak southerly change were long-lived. Afternoon storms in the northeast unusually propagated westward into the evening. The animation shows hourly lightning tracker and radar frames from about 2am to midnight. Weatherzone, BoM, Kattron.
NSW: Storms batter Sydney and Central West
A complex weather pattern over NSW today produced widespread and unusual storm development. The storms brought damaging lightning strikes, strong wind gusts and patchy torrential rain and in some places lasted for 6 to 8 hours.
Eastern NSW continues to lie under a very moist, unstable airmass in which any mechanism that triggers uplift is likely to produce thunderstorms. At the surface, northeasterly winds feed into a trough, but above about 3km the winds turn sharply westerly and strengthen. This wind sheer enhances storm development by promoting updraft. The entrance to a weak jet stream also lay over central NSW this morning, the accelerating upper air further enhancing upmotion.
A very weak southerly change pushed up the NSW Central Coast early this morning, the result of a Southern Ocean cold front dragging the surface trough temporarily eastwards. This moved the remnants of the previous day's storms out to sea, but the wind convergence it set up sparked a new line of storms visible in the lightning animation's 3.50am frame extending SW from Newcastle. New storms continued to form along the convergence zone of the advancing southeasterlies as it moved inland to about Cowra. Successive cells then moved ENE along this line for the remainder of the morning and into the early afternoon, giving some locations 6 of more hours of near-continuous lightning, thunder, and bouts of heavy rain.
The surface trough became disconnected from the cold front late morning and retreated into western NSW during the afternoon. Consequently, storms that developed due to daytime heating in the moist unstable air over NE NSW progressively developed further to the west into the evening.
The SES received about 170 calls for help across the state, while Fire Brigades and the Rural Fire Service were also kept busy. Over 35,000 properties were blacked out, mostly in Sydney and the Central West, because of downed powerlines or lightning affecting electrical distibution systems.
In the Central West:
- Lightning continued for much of the day and started fires in areas where no rain fell. The Rural Fire Services was called in to stop blazes west of Manildra, at Cumnock, Cargo, Neville, Mandurama and Blayney. An area south of Orange around Blayney had near-continuous lightning from before 3am to after 5pm. RFS spokesman Brett Bowden said "When you look at the [lightning data for the Central West] map it is something like hundreds of thousands; there was massive activity." He said the Blayney area bore the brunt of the strikes: "The area was absolutely hammered out there."
- SES spokesman Phil Campbell said there had been flash flooding and trees blown onto houses in Orange and Bathurst. Rain from the storms was exceptionally variable. The SES reported up to 70mm at an unspecified location, while in the Bureau network Bathurst recorded 38 and Newbridge 31mm from the storms. Many locations recorded little or none.
- About 8,000 properties were blacked out in Orange and Bathurst, together with some in Young and Cowra.
- Lightning caused house fires at Rooty Hill and Bella Vista 15km northwest of Parramatta, and a gas main fire at Erskine Park. At Hornsby Heights, Grace Iwanoczko, 69, was in bed reading when lightning struck a tree about 4m from her window at 8.15am. The bolt travelled underground before blowing a hole in the wall, less than 1m from her bed. "There wasn't any warning," she told the Daily Telegraph. "The lightning lit up the room, there was just stuff everywhere, the blinds were smouldering."
- Torrential rain, strong winds and violent electrical activity focused on Sydney's western suburbs and Blue Mountains. Willmot, 8km NE of Penrith, recorded 45mm in the hour to 8am and Woodford in the Mid Mountains 42mm in half an hour, but storm falls across the metro area were mostly between 10 and 25mm with southern suburbs recording 10mm or less. Most of about 60 calls for assistance received by the SES were from the western suburbs of Lethbridge Park, Mount Druitt and Penrith.
- Powerlines were brought down at Emu Plains, Penrith, Lethbridge Park and Blacktown. Power was cut to about 26,000 properties from Penrith to Dundas and in South Granville, and another 1,000 around Hornsby and Arcadia.
In the north and northwest:
- A storm raged around Coonabarabran in the state's central north for over an hour, giving the airport on a ridge to the south of the town a wind gust of 119km/h at 2.30pm and dumping 68mm in the raingauge, most in the hour from 2.20 to 3.20pm. 11mm fell in 6 minutes to 2.30 and 31mm in 21 minutes to 3.01.
- Blackouts were reported in Kempsey and Grafton.
|Rainfall for the 24 hours to 9am on the North Coast (above) and Burdekin (below). BoM
QLD: Flooding on North and Central Coasts as rain intensifies
Rivers between Cardwell and Mackay were in minor to major flood today as an area of rain giving 100 to 200mm over 9 to 12 hours moved south. The low that has been moving down Cape York Peninsula over the past few days was northwest of Townsville this morning, still moving slowly south and drawing saturated E to NE winds onto the coast and into the country to the southeast of the Gulf of Carpentaria. As the low moved south, rain eased north of Townsville during the day but intensified farther down the coast towards Mackay.
The highest rainfall for the 24 hours to 9am in the Bureau's official network was 165.2 at Giru near Townsville, with Einasleigh in the Upper Carpentaria close behind on 151.0 (See wettest for more figures). However, an area on and east of the Paluma Range, 50km WNW of Townsville, recorded the highest rain to 9am. The official gauge at Paluma, situated on an escarpment that rises to 1,000 just 10km from the coast, came in with a 3-day reading of 434mm, with the nearby flood network gauge reporting 311 for the 24 hours (119mm falling between 3 and 6am). About 6km east at the bottom of the mountain, Paradise Lagoon flood gauge recorded a 24 hour total of 359mm (246 falling between midnight and 9am). Most readings on the coastal strip north of Townsville and into the headwaters of the Haughton River to the south of the city were between 100 and 200mm, with the heaviest rain starting about 9pm yesterday. Heavy short-duration falls from the Bureau's official network are below.)
Rapid rises occurred in response to this in the streams north of Townsville, but only reached minor flood levels when the rain eased late morning. In the Haughton, rain eased after midday, and the river peaked at Powerline at 7.67m with moderate flooding at 11pm and at Giru near the coast at 2.75 overnight into Monday with major flooding.
As the low tracked south, flood rain fell in the Don, Proserpine and Pioneer catchments south to Mackay between about midday and midnight. Guthalungra flood gauge 45km west of Bowen recorded 268mm between 9am and 6pm (see tomorrow's summary for rainfall details for the 24 hours to 9am Monday). The Don River at Bowen Pump Station peaked at 4.79 metres at 11pm today with minor flooding, though river gauges upstream reported brief periods of moderate flooding during the afternoon and evening. The Pioneer Valley above Mackay also saw brief periods of minor flooding.
Many secondary roads between Townsville and Mackay were closed by flooding. Main roads closed included the Bruce Highway with the flooded Haughton River at Giru and between Home Hill and Bowen, the Flinders Highway between Charters Towers and Hughenden, and the Gregory Developmental Road south of Charters Towers. A truck driver had to be rescued from his submerged truck after he attempted to cross the flooded Bohle River just west of Townsville this morning. Two people were killed and three injured in a crash in heavy rain that involved two cars and a semi-trailer on the Bruce Highway 60km NW of Mackay early this afternoon. Ten tourists had to be rescued by an SES flood boat when they were caught by rising floodwater at Cedar Creek Falls near Proserpine.