SIGNIFICANT WEATHER - DECEMBER 2000

Summary Tropical Cyclones Thunderstorms/Tornado Flooding Dust Storms Snow Wind
Bushfires Temperature Rainfall

SUMMARY

Tropical cyclone Sam crossed the northwest Western Australian coast near Broome on the 8th. Severe storms affected Queensland, Victoria and the Northern Territory. Continued heavy rain over parts of Queensland resulted in prolonged flooding inland. Many Queensland and Northern Territory locations reported record monthly rainfalls for December and a new record has been set for the highest annual rainfall recorded in Australia in a calendar year. Bellenden Ker, southwest of Cairns has recorded 12461 mm in 2000. A cold outbreak around Christmas resulted in snow on the Tasmanian highlands.

TROPICAL CYCLONES

Western Australia

A developing low was named tropical cyclone Sam on the 5th, while located approximately 315 kilometres north northeast of Derby. Tropical cyclone Sam initially moved on a westerly track but then turned to the south and southeast and tracked towards the coast. Tropical cyclone Sam crossed the Kimberley coastline 110 kilometres south of Broome, near Bidyadanga on the evening of the 8th. Wind gusts near the centre were estimated to be greater than 250 km/h with rainfall on the order of 200-300mm. Shelamar, just south of Bidyadanga, reported 520mm of rain in the 48 hours to 9am on the 10th. Most people in the area were evacuated before tropical cyclone Sam hit with preliminary reports indicating severe damage to station homesteads, sheds and buildings. Most trees were blown over with power cut for several days. The system had weakened to a tropical low by the 10th and the final warning was issued by the Bureau as it headed towards the remote Great Sandy Desert region.

THUNDERSTORMS/TORNADO

Queensland

On the 12th Near Warwick, thunderstorms with reported large hail and strong winds were observed on the southern border ranges near Allora. At approx 5 pm 90 to 100 km/h winds were reported and hail 3-4cm in diameter from the intersection of the New England and Cunningham Hwy.

On the 18th, a severe storm hit areas of Mount Isa between 7pm and 9pm. The majority of damage reported was caused by local flash flooding. Areas such as Sunset appear to have been the worst affected with up to half a metre of water under some residences. Commercial industries adjacent to Sunset Bridge were badly affected by flood waters, with the bridge itself sustaining some structural damage from rushing waters. A train approximately 40 kilometres south of Mount Isa reported hail 5cm in diameter with some as large as golf balls with very heavy rainfall.

On the 25th near Kilcoy, a severe thunderstorm was observed on radar in the Maleny-Jimna area at approximately 7pm and a report of 72mm of rain in an hour was received from this storm.

New South Wales

On the 1st, hail 2 cm in diameter was reported at Junction Hill near Grafton (Northern Rivers). In the Cabramatta area (Metropolitan), hail 3 cm in diameter fell for 20 minutes. Golf ball size hail, very heavy rain, flash flooding and wind damage was reported in the Campbelltown area. Severe size hail affected Western Sydney as the storm progressed to the North. The SES attended 178 jobs for excessive hail in gutters, trees were blown down and there was local flooding. A wind gust of 96km/h was measured at Pt Perpendicular (Illawarra) and a gust of 93km/h was recorded at Norah Head (Hunter).

On the 6th, hail 4 cm in diameter and a funnel cloud was reported at Putty (Hunter), hail 2 cm in diameter was reported at Bathurst (Central Tablelands).

On the 7th, golf ball size hail damaged some cars at Nymboida (Northern Rivers), wind gusts estimated at up to 120 km/h caused damage to houses in Manilla (North West Slopes), wind also damaged some houses at Gunnedah (North West Slopes). Golf ball size hail was reported at Singleton (Hunter), a wind gust of 113 km/h was recorded at Casino Airport (Northern Rivers) with 29.6 mm of rain in 25 minutes. At Parramatta (Metropolitan) hail 3 cm in diameter was reported.

On the 8th, funnel clouds, hail 4.5 cm in diameter and winds estimated at 89 km/h caused tree damage during a 15 minute period at Lawrence (Northern Rivers), hail 4 cm in diameter was reported at Uralba.

On the 13th, hail 2 cm in diameter was reported at Orange (Central Tablelands), hail 3 cm in diameter was reported at Bilpin (Central Tablelands). Hail 4 cm in diameter and flash flooding was reported in the Cranebrook area (Central Tablelands).

On the 27th, trees and houses were damaged at Tamworth (North West Slopes) and there were reports of flash flooding.

On the 29th, 40 mm of rain in 30 minutes was recorded at Nundle (North West Slopes) and 40 mm of rain in 30 minutes was recorded at Coffs Harbour (Northern Rivers).

Victoria

On the 21st in the Melbourne area, storms produced damaging winds, the SES received over 400 calls for assistance. Wind damage was also reported at Maldon and Malmsbury. At Winton in the Northeast, wind damage to trees and buildings was reported. In the Eastville/Bonnie Banks area (Northern Country) severe wind lifted sheets of tin off houses and sheds and some trees were felled, damage was confined to a narrow path.

On the 22nd, heavy rain in the afternoon caused local flooding in the Melbourne Metropolitan area.

On the 27th, hail up to 2cm in diameter was reported at Blairgowrie on the Mornington Peninsula, 30mm of rain was recorded in 1 hour.

Northern Territory

On the 3rd, a waterspout/weak tornado caused damage at Crab Claw Island resort at Bynoe Harbour near Darwin during early evening. Several other waterspouts/tornadoes were reported in the Cox Peninsula on the 3rd.

FLOODING

Queensland

At the beginning of December flood warnings were current for 4 river basins in western Queensland, as a result of widespread rainfall in November. In the middle of December, more heavy rainfall occurred, again in western Queensland, due to tropical cyclone Sam, with flood warnings issued for 6 river basins. Flood warnings were also issued for Don River on the north tropical coast at the end of the month. A total of 103 flood warnings were issued for 8 river basins during December.

Don River:
Heavy rainfall overnight on the 28th and the following day resulted in river rises and moderate flooding in the lower reaches of the Don River at Bowen. Flood warnings were issued on the 29th and finalised on the 31st.

Paroo River:
Minor to moderate flooding continued in the Paroo River into December following rainfall in November. At the beginning of December, the main floodwaters were in the Hungerford area and high moderate flood levels were maintained for the first week.

Bulloo River:
Similarly to the Paroo, minor to moderate flooding continued in the lower Bulloo River into December. At the beginning of the month the main floodwaters were at Thargomindah and high moderate flood levels were maintained for the first week.
Heavy rainfall in the upper reaches of the Bulloo River during the middle of December caused river rises to the major flood level at Quilpie on the 20th. Minor flooding continued downstream with the floodwaters peaking at Thargomindah at the moderate flood level on 29th.

Thomson and Barcoo Rivers and Cooper Creek:
At the beginning of December minor to moderate flooding was occurring in the lower Thomson River from Bogewong to Jundah, with the floodwaters in the Jundah area. Minor flooding was easing in the lower Barcoo River and moderate flooding was easing in Cooper Creek from earlier peaks. The floodwaters in the lower Thomson River did not significantly impact on river levels at Windorah and the flood warnings were finalised on the 7th, when all river levels were falling.
Widespread moderate to heavy rainfalls occurred in the upper Thomson and Barcoo River catchments on the 14th and 15th. This caused rises throughout the river system with minor flooding upstream of Longreach and moderate flooding downstream of Longreach to Jundah. River levels at Longreach did not reach the bridge level. River levels peaked at Jundah on the 20th. Minor flooding occurred in the upper reaches of the Barcoo River at Blackall with major flooding occurring from Isisford to Retreat.
The floodwaters reached Windorah on Cooper Creek by the end of December. River levels were above the major flood level of 5 metres from the 22nd to the 27th, with a flood peak on the 27th. Further scattered heavy rainfall at the end of December in the upper Thomson River catchment caused renewed rises upstream of Longreach. River levels at Longreach reached the minor flood level on the 30th and high river levels above the main bridge level were maintained into January.

Diamantina River:
Heavy rainfall in the upper catchment of the Diamantina River in the middle of December resulted in moderate flooding recorded at Elderslie and Diamantina Lakes. High river levels receded relatively quickly at Elderslie but moderate flooding and high river levels were maintained at Diamantina Lakes from the 17th to the end of the month. The main floodwaters were approaching Monkira by the month.

Georgina River:
Continuous heavy rainfalls in the upper Georgina River catchment between about the 11th to the 29th, caused moderate to major flooding throughout the Georgina River and Eyre Creek system. By the end of the month, the main flood waters had peaked at Glen Gyle on Eyre Creek, with major flood levels easing very slowly upstream of Glen Gyle.

Gulf Rivers:
Rainfall in the western Gulf in the middle of December caused sharp rises in the Nicholson River at Doomadgee with major flooding between the 11th and 13th. These floodwaters did not have a significant impact downstream. However continuing rainfall for the rest of the month resulted in major flooding occurring in the lower Nicholson, Gregory and Albert Rivers. River levels at Burketown peaked at 6.60 metres on the 31st, just below the level where the town is affected.
In the Leichhardt River, continued rain from the 6th to the 29th resulted in a number of rises with minor through to major flooding developing. The main floodwaters finally peaked in the lower reaches at Floraville on the 30th with major flooding.
In the Flinders River, two significant periods of rain in the latter half of the month resulted in two peaks at Richmond with moderate flooding. Similar peaks were recorded at Cloncurry on the Cloncurry River. The combined floodwaters from the first period of rainfall from the 14th to the 18th, peaked at Walkers Bend on the 30th at the major flood level.

DUST STORMS

Queensland

Longreach reported a significant reduction in visibility chiefly due to dust on the 14th.

SNOW

Tasmania

Highland snow around Christmas, coupled with other adverse weather, hampered search efforts for a missing bushwalker. The search was eventually abandoned without success.

WIND

Victoria

On the 24th, severe wind gusts occurred in Southern and Alpine districts. Gusts exceeding 90 km/h were recorded by the following AWS's - Wilsons Promontory 130 km/h, Mt Gellibrand 98 km/h, Falls Creek 91 km/h, Sale 90 km/h, Mt Hotham 90 km/h and Mt Hotham Airport 90 km/h. On the 26th, wind damage occurred at Frankston and the SES attended a few jobs.

Tasmania

Gales on Christmas Eve caused scattered damage across Tasmania, particularly to the state's poppy crop. "Devil Cat" services across Bass Strait were cancelled or disrupted from the 24th to the 27th.
Gusts exceeding 90 km/h were reported at Launceston Airport on the 24th; Wynyard Airport on the 24th; Devonport Airport on the 24th; Cape Grim BAPS on the 21st, 22nd, 23rd, 24th, 25th, 27th and 29th; Luncheon Hill Forestry on the 24th; Smithton Aerodrome on the 24th; Eddystone Point on the 23rd and 24th; Friendly Beaches on the 24th; Hobart Airport on the 24th; Hobart on the 23rd and 24th; Maatsuyker Island on the 3rd, 11th, 12th, 13th, 14th, 19th, 20th, 22nd, 23rd, 24th, 25th and 28th; Mount Wellington on the 3rd, 8th, 12th, 13th, 20th, 22nd, 23rd, 24th, 25th, 26th, 27th, 28th and 29th; Hartz Mountain on the 11th, 22nd, 23rd, 24th, 28th and 29th; Barren Tier on the 23rd and 24th; Strahan Aerodrome on the 24th; King Island Airport on the 24th; Flinders Island Airport on the 24th and 26th and Derwent Estuary TERS Site on the 5th, 13th, 23rd, 24th, 25th, 27th, 28th and 29th.

BUSHFIRES

Queensland

On the 7th, a bush fire at Hirstglen (near Cambooya) burnt over an area in excess of 600 hectares.

Victoria

On the 17th, a grass fire started at Dadswells Bridge (Wimmera District) and burnt approximately 14,400 hectares.

On the 20th, a fire weather forecaster was outposted to Stawell to provide "on site" fire weather services. Although there have been no reports of any houses being lost, damage was considerable. There were major stock losses, and several farm outbuildings, haysheds and many kilometers of fencing were damaged.

Tasmania

Bushfires were reported at scattered locations on the 1st.

A fire burnt near Poatina around the 20th and 21st.

Several scrub or grass fires occurred in the southeast on the 20th and 25th.

Western Australia

From the 27th to the 31st, several bush fires that were started by lightning strikes, burnt up to 100,000 hectares in the states South, Midwest and Goldfields. Bushfires destroyed two houses and claimed more than 10,000 hectares of bush between Mt Barker and Cape Arid, east of Esperance. Wildfires spread through more than 85,000 hectares of bushland at Mt Gibson, northeast of Dalwallinu while several fires began near Southern Cross and the Goldfields.

Northern Territory

Fresh and dry easterly winds caused a period of high fire danger in the Alice Springs district during the first week of December. Several fires around the perimeter of the Alice Springs town area threatened properties on the 9th and 10th. One grassfire swept through three rural blocks in the Ilparpa Valley, south of Alice Springs, destroying a shed, caravan and mobile home.

TEMPERATURE

RAINFALL

Queensland

A new record has been set for the highest rainfall recorded in a calendar year at an Australian station. The summit of Bellenden Ker, south-west of Cairns, recorded 12,461 millimetres of rain in 2000, breaking its own 1999 record of 11,852 mm by 609 mm.

Western Australia

Kimberley Coastal Camp which opened in 1995 has set the highest annual rainfall total for Western Australia with 2,337.8 mm in 2000, well above the Jarrahdale Post Office total of 2,169.4 mm which was set in 1917.

Note: Some statistical records mentioned in this report are based on data that have yet to be fully validated.