Cold
wet weather dents the drought, fires and record books in NSW 
14/12/02
SE Qld storms
bring heavy rain 14/12/02NEWSBITS: Record cold December morning in SA, Qld
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 The best rain since April drenched much of the NSW and SE Qld seabord today. The map above shows rain for the week ended 9am Wednesday, but most of the rain in NSW and southern Queensland fell during the last 48 hours. The map below shows the maximum temperature departure from normal, with a large swathe of country experiencing top temperatures between 8 and 17° below average BoM |
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The unexpected development of a significant upper low gave eastern NSW widespread moderate to heavy rain today. Bushfires were extinguished or substantially retarded, and some of the state's driest areas received heavy, soaking rain. While the rain is not enough to be considered drought-breaking, it will give many farmers the go-ahead to plant summer crops.
An upper trough and cold pool moved in behind a surface trough lying across the state's northeast late Monday and progressed slowly northeast during today, developing into a closed upper low over southern Queensland by Wednesday morning. Northerlies ahead of the surface and upper trough systems over the past few days have brought a plentiful supply of moisture down into eastern NSW and SE Qld. Meantime, a substantial jet stream over southern Queensland produced respectable vertical ascent over NE NSW/SE Qld, enhancing the broadscale convergence in the troughs and developing low.
A broad area of rain developed on Monday evening over the Southern and Central Tablelands under the upper trough and extended to the South Coast by early this morning. During the morning it moved very slowly northwards, stalling during the afternoon over the Hunter and Central Coast. It stayed in this general area for 24 hours, producing soaking rains upwards of 100mm across much of the drought-stricken Hunter Valley. Most of the rain for this event fell during the 24 hours to 9am Wednesday, (where a gratifyingly long list of rainfall totals exceeding 50mm can be found). December daily rainfall records were broken at Quirindi, Woolbrook, Murrurundi, Cessnock (Nulkaba), Paterson (Tocal), Lostock Dam, and Peats Ridge, and probably at other locations yet to report. The records at Quirindi and Murrurundi had stood for 116 and 128 years respectively. The heavy rain in the Manning has led to the lifting of water restrictions from Crowdy Head to Forster/Tuncurry, while soaking rains in the Hunter Valley wine regions have saved the 2003 vintage from very low yields.
Soon after sunrise this morning, a line of storms developed along the surface troughline from Newcastle to around St George in central southern Queensland. The line intensified and broadened as it moved northeast with the surface trough over the next 12 hours, bringing some heavy short-duration falls to the North and Mid North Coasts and Northern Tablelands and Slopes (see the high short-duration rainfall box below). The highest falls in the nation were 168mm at Upper Chichester, 155.8 at Stroud, 154.6 at Laurieton and 154.2 at Upper Allyn, which had the benefit of both the thunderstorms and the prolonged period under the stalled rainband, as well as orographic enhancement from downwind mountains. Strong winds and a possible tornado accompanied the storms at Ballina, where at least 5 buildings including the fire station were unroofed and damage was caused to trees and small structures. Damage was also reported from Lismore, Murwillumbah and Nimbin, and the Lismore - Nimbin Road was closed by fallen trees.
The day was unusually cold under the extensive cloudband accompanying the upper trough, and particularly so in the persistent rainband. Sydney's top temperature of 16.1° was the coldest December day since 1924, while Katoomba only made it to 8.5. In the Central West, Trangie, Peak Hill, Parkes and Grenfell all recorded tops of around 15°, which is between 15 and 17 below normal.
The storm band that moved across NE NSW during the day began producing torrential rains over the Darling Downs mid afternoon with Miles reporting 15.2mm in 8 minutes, Oakey 11.4 in 7 minutes and Stanthorpe 9.4 in 5 minutes. Strong wind caused damage to a house, sheds and trees at Tara, northwest of Toowoomba. By 5pm a slow-moving line of storms extended from off the Gold Coast, across Brisbane to the Sunshine Coast hinterland. Brisbane Airport recorded a wind gust of 121km/h and received 25.6mm of rain in 10 minutes while Brisbane City had 37.6mm in 21 minutes. Most locations in the metropolitan area recorded between 30 and 60mm in all from the storm. The combination of lightning strikes, wind and rain brought down trees and powerlines across Brisbane and the Gold Coast, blacking out aover 100,000 properties and delaying electric train services. Local flooding in Brisbane caused peak-hour traffic chaos and flooded shops in the city's Queen Street Mall. Homes were damaged at Mitchelton in Brisbane's north, and Nerang, Burleigh and Labrador on the Gold Coast.
At one point during the early evening, the line of storms stretched over 600km from off the NSW North Coast to west of Rockhampton Qld. North of Brisbane at Gympie, where wind gusted to 91km/h, 22 homes and four businesses suffered roof damage, while one house lost its whole verandah. Inland, extensive damage was caused in the Biloela and Thangool area, with a house and many units of a motel unroofed in Thangool, trees and powerlines down, and the Burnett Highway that passes through the two towns closed for 6 hours by fallen powerlines. The Insurance Council expects the damage bill from the storm event to reach at least $1.5m.
NEWSBITS: While the cold pool was giving rain and storms to eastern parts of NSW and Queensland, the cool dry air under cloudless skies in its wake produced a cold December morning in western NSW, SW Qld and eastern SA. Birdsville Qld had their coldest December morning in 45 years of computerised records when the mercury dropped to 10.9°, while Leigh Creek, north of Port Augusta SA, recorded 9.1, its lowest in a shorter 12 year record.