Summary
A middle-level circulation was identified on radar within the monsoon trough on 27 February near Weipa (on Cape York Peninsula). By 28 February a surface low became evident, and began to move slowly west across the Gulf of Carpentaria. On 1 March the low began to rapidly deepen and shift west-southwest. Evan briefly reached tropical cyclone intensity before making landfall on Groote Eylandt , in the western Gulf of Carpentaria. After weakening, the tropical low passed over the Top end and out into far southern parts of the Joseph Bonaparte Gulf, but conditions were not favourable for the system to redevelop.
Evan formed in the monsoon trough, assisted by an upper-level trough in the region and the subsequent low shear environment. Development of the low was hampered by the position of the upper-level ridge at 15-20°S, resulting in good outflow in only the southern section. A low-level easterly wind surge on 1 March, in combination with good northwest monsoon low-level convergence, resulted in a more favourable environment. Upper-level outflow improved and the easterly vertical wind shear reduced during the day, causing the system to deepen rapidly before reaching cyclone intensity in the afternoon. Evan made landfall on Groote Eylandt only a few hours later, then progressed onto the mainland coast.
Groote Eylandt sustained some wind damage, with trees falling on power lines and a boat sinking in the harbour. On 2 and 3 March the resultant rain depression moved westward across the Top End, causing flooding in many catchments. Residents were evacuated from the outskirts of Katherine and the Stuart Highway was cut south of Katherine on 2 March.
Track and intensity
All times in UTC - add 9.5 hours to convert to CST.
