Charts of the past with Blair Trewin
BAMOS March 2023
23
21 February 1993
February 1993 was a month of significant wet season rainfall through large parts of northern Australia . A tropical low at the start of the month brought flooding to the West Kimberley and Pilbara , whilst a long-lived low was associated with widespread rain in northwest Queensland . This low never reached cyclone intensity but was present for much of the month , and was ultimately responsible for major flooding in northwest Australia .
The low began to move westwards in mid-month and by the 16th was centred over the central Northern Territory . Continuing to move slowly westwards , it reached the Kimberley coast near Derby on the 21st , with its central pressure falling below 996 hPa . At this point , it reversed direction and started moving eastwards again , stalling near Halls Creek from the 23rd and gradually weakening in situ over the following days , before being absorbed into the broader monsoon trough by the end of the month .
The low brought heavy rain over the week from 18 to 24 February over a broad band extending east from near Derby , across the central and southern Kimberley and extending into the Northern Territory . Most of this area received at least 200 mm for the week with some parts , particularly near the west coast , exceeding 400 mm . The heaviest falls were at Mount Hart , about 150 km east of Derby , which had over 100 mm on each of the three days 21 to 23 February , and a three-day total of 452 mm . The heaviest single-day total was 190 mm at Brooking Springs , near Fitzroy Crossing , on the 22nd . Fitzroy Crossing had at least 18 mm on each of the six days from 19 to 24 February , and a total of 298 mm .
The rain led to major flooding throughout the region , especially in the Fitzroy River , which reached one of its highest levels on record at Fitzroy Crossing . Whilst not as severe as in 2023 , there was still widespread inundation and major damage to the road network in the region , with transport links closed for an extended period and significant agricultural losses . With the rain earlier in the month , it was the wettest February on record over significant parts of the Kimberley and adjacent parts of the Northern Territory .
At the same time , another low was affecting southeastern Australia . After a strong front crossed the region on the 20th , a low formed near Tasmania , moving north to be near Gabo Island on the 22nd before moving south again over Tasmania and weakening . This low brought significant rain to some areas , with four-day totals above 50 mm in southern Tasmania , west
Gippsland and the eastern suburbs of Melbourne , and parts of the Alps .
The most significant feature of this system was abnormal cold for late summer in the persistent southerly to southwesterly airstream on the west side of the low . Snow fell in the New South Wales and Victorian mountains , and maximum temperatures on the 22nd of 1.6 ° C at Falls Creek and 2.0 ° C at Perisher Valley were state February records at the time ( subsequently broken in 2005 ). Forbes ( 15.0 ° C ) and Cobar ( 16.1 ° C ) had their coldest February days on the 21st . There were also some very cool nights where skies cleared and winds moderated . Mildura ' s 5.2 ° C on the 22nd was a February record by 1.4 ° C , while other centres to set February records included Cobar and Dubbo . Temperatures fell to near freezing in parts of Victoria and eastern South Australia , including 0.5 ° C at Ballarat , 1.0 ° C at Mount Crawford in the Adelaide Hills , and 2.0 ° C at Kybybolite in South Australia ' s south-east . Adelaide ' s 9.5 ° C was its lowest in February in the last 60 years , and Melbourne ' s 9.6 ° C its most recent minimum below 10 ° C in February . The cold air reached as far north as New England , where Woolbrook equalled its February record with 1.0 ° C .
Synoptic chart for 0000 UTC , 21 February 1993