BAMOS Vol 33 No.1 March 2020 | Page 23

Charts of the Past BAMOS Mar 2020 with Blair Trewin 24 January 1941 1940 was a significant drought year in many parts of eastern Australia. It is the third‑driest year on record for New South Wales and in the driest ten for South Australia and Victoria. The second half of the year was particularly dry, with less than 10 mm falling across a large area of the eastern outback. There was a marked pattern shift in early January 1941, with regular rain across northern Australia, and widespread heavy falls in inland NSW and northern Victoria in the first week of the month. The most significant rain event of the period developed later in January. A low developed over the Nullarbor on the 23rd, drawing moisture from an active monsoon trough over northern Australia. The low moved eastwards on the 24th, linking with tropical systems to draw a moist northerly flow over many parts of eastern Australia. The southern centre of the low, which had been near Port Augusta on the 24th, then continued to move southeast, deepening as it moved offshore east of Bass Strait on the 26th. Initially, the heaviest falls were in northern Australia. Alexandria, in the eastern Northern Territory, had 306.4 mm on the two days 22–23 January, and each of the 22nd, 23rd and 24th had daily totals exceeding 100 mm at one or more sites in far western Queensland. The heaviest rain spread into southern Australia over the next two days. On the 25th, heavy rain fell in a region extending from the upper Spencer Gulf in South Australia to the Wimmera in western Victoria. The heaviest falls were on the eastern side of the Mount Lofty Ranges, including 173.7 mm at Mannum and 142.2 mm at Strathalbyn, the wettest day on record at both locations. A second area of extreme rainfall was located north of Adelaide, with totals, also records, of 138.4 mm at Port Wakefield, 133.9 mm at Balaklava and 111.8 mm at Clare, whilst in Victoria 105.4 mm fell at Natimuk. Severe local flooding occurred in both regions. Amongst the worst was at Jamestown, where much of the town centre was flooded and losses of several hundred thousand pounds were reported, whilst major damage also occurred at Port Wakefield, Laura, Port Pirie and Strathalbyn. Numerous moored vessels were swept out to sea after breaking their moorings at Victor Harbor, whilst railways were blocked by washouts in many places and several thousand acres of cropland was inundated near Tailem Bend. Despite the flooding, the rains were generally seen as beneficial to farmers and pastoralists after the preceding drought. The next day, the heaviest rains moved into Victoria. Especially intense rain fell west and north of Melbourne. A site near Blackwood recorded 228.1 mm, the second‑highest January daily fall in Victoria, whilst other falls included 143.0 mm at Mickleham, 139.7 mm at Watsonia and 135.9 mm at Sunbury. Melbourne itself had 80.3 mm over two days. A second area of heavy rain in southern NSW saw 116.8 mm at Narrandera and 113.3 mm at Berrigan. Local flooding occurred in the Werribee River and Kororoit Creek, inundating an army camp at Williamstown, and Melton Reservoir went from near‑empty to full within a day. Two men were lost at sea in Port Phillip in westerly gales. The rain cleared to Gippsland next day, with 101.6 mm at Lakes Entrance. With the dry antecedent conditions, only minor flooding occurred in major rivers. The period was also very cool; four consecutive days below 15 °C at Hobart were a January record, while several South Australian locations had their coldest January day on record on the 24th or 25th, including Kyancutta (17.2 °C), Snowtown (14.1 °C), Robe (13.0 °C) and Mount Gambier (12.8 °C). In total, eight deaths were attributed to the event: two in South Australia, two in Victoria and four in flash flooding in southeast Queensland, where several were injured when a train hit landslide debris on the Toowoomba Range. A circus elephant was (unsuccessfully) deployed to push a stranded boat back into the flooded Bremer River at Ipswich. January 1941 is the wettest on record in some parts of South Australia, Victoria and inland Queensland, and the second‑wettest for Victoria as a whole (as well as the coolest for NSW and South Australia), but it proved to be only a brief respite. The remainder of 1941 turned generally dry again as El Niño returned for a rare second consecutive year, and long‑term drought affected the Murray‑Darling Basin until 1946. Synoptic chart for 0900 AEST, 24 January 1941. 23