The development of a strong low pressure system associated with a double cold front structure last weekend brought a substantial drop in maximum temperatures and some thunderstorm activity. Rainfalls were light in our regions. Maximum temperatures before the change rose to near 30 degrees on last Saturday 8th April and had dropped more than 10 degrees at many places on the Sunday. Earlier last week there were hot conditions in WA . Carnarvon had a temperature of 39.6 which was the highest April temperature since 1998.
Last month Alice Springs had it's hottest March since 1880 with a mean maximum temperature of 36.9. Other hot March's in Alice Springs were in 1914, 1951, 1986 and 1999. These five cases did lead to moderate rainfalls in our regions late in April and again late May.
Late last month there were unseasonably high temperatures recorded at Wilcannia, Tibooburra, Cobar and Hillston. Both Wilcannia and Tibooburra recorded a maximum temperature of 44 degrees on 27th March, very late indeed. Wilcannia's 44 degrees was the highest March temperature since 44.5 on 18th March 1927. On top of one of the hottest summers on record at Wilcannia it has been the hottest December to March period there since 1991. Other very hot December to March periods at Wilcannia were in 1892, 1893 and 1923. The autumn seasons of those four episodes were notably warmer than average in our regions and the heaviest rains were late in May or early June which does suggest the rainfall this April will fall short of average at most places in our regions.
The active cold change will delay the return to warmer than normal days until about the third week of April. More warm days are anticipated for first half of May.