Blustery
change gives best rain in months to SE Australia 
21Mar01Melbourne,
Canberra break record for summer warmth 21Mar01
Active
monsoon brings more rain to tropical Australia |
| Surface charts from 5pm Friday to 5am Sunday in 6-hourly steps. A wave has already developed on the front at 5pm Friday as it approaches Bass Strait. Twelve hours later, the front has nearly crossed Victoria, and an enclosed low has developed off NW Tasmania. During Saturday, the low deepens to 995hPa as it moves slowly through the Strait, dragging rain clouds SE across Victoria and Tasmania. BoM |
A front crossed Victoria overnight preceded by a trough that amplified northeastwards into NSW before petering out near the Great Divide. Meanwhile, a small low developed in western Bass Strait early this morning, the result of cold air moving in with the front and a strong southwesterly jetstream over western Victoria. This low deepened to 995hPa as it moved through the Strait during the day, bringing gales to Victoria and Tasmania, and dragging a considerable rainband SE across Victoria and Tasmania. It was not a day to be out in Bass Strait, with winds gusting to 132km/h at Wilsons Promontory Lighthouse, and to 109km/h over open water at the Kingfish B oil rig off Sale. Details of top gusts are below.
All of Victoria except the Mallee and Wimmera received between 10 and 50mm of rain, with some locations in the east recording up to 65mm. In Tasmania, most of the state except the southeast recorded over 25mm. Along the north coast, many locations recorded between 50 and 70mm as the low skirted close to the coastline. The rain brought optimism to farmers, particularly in parched southern Victoria and in the central highlands, southern midlands and east coast of Tasmania where summer rainfall has been in the lowest 10% of falls in the past century. Irrigation bans, which have been in force for many northern Tasmanian streams, were lifted on the Meander River following the rain, and were being reviewed for other northern rivers. Parts of western Victoria have received only half their normal summer rain. The maps below show the areas that benefited from the rainband, and the areas of serious rainfall deficiency. General rains of 25 to 50mm also fell across central NSW and the Southern Tablelands and Slopes, with some heavy falls in thunderstorms. Rainfall registrations of 50mm or more are given below.
| Left: Rainfall for
the week ended Sunday 18 March. Most of the rain shown in Victoria
and Tasmania fell in today's event. Right: Rainfall deciles for the summer just finished. Areas of deep red are in the lowest 10% of summer rainfalls on record. BoM |
Today was the first day since 28 December that the maximum temperature in Melbourne has failed to reach 20°. For 78 consecutive days, a top temperature of 20 or above has been recorded at the Lonsdale Street site, breaking the previous record of 70 consecutive days set in 1956. As Melbourne's records date back to 1855, this is a significant measure of the warmth of this summer in southern Victoria. Across Victoria as a whole, this summer was one of the warmest on record, with minimum temperatures 2 to 3 above normal and maximum temperatures 1 to 2 up. Canberra, too, had a record number of consecutive days with temperatures equalling or exceeding 20° -- 120, from 17 November to 16 March. The previous record was 109 days set in 1997/98.
A rejuvenated monsoon brought widespread falls of between 50 and 100mm across the WA Kimberley, the NT Top End and the Queensland Peninsula and Northern Tropical Coast areas. Details are below.