[2] Concurrently, the Joint Typhoon Warning Center (JTWC) classified Aivu as Tropical Cyclone 23P, also estimating winds to have reached gale-force.
[1] Tropical cyclone formation within Port Moresby's area of responsibility (AOR) is relatively uncommon, though usually linked with cool La Niña events.
[4] Early on 3 April, the cyclone attained its peak strength with winds of 205 km/h (125 mph) and a barometric pressure of 935 mbar (hPa; 27.61 inHg).
[5] The estimate stemmed from the Dvorak technique — a method of analysing a tropical cyclone's intensity using satellite imagery — as values reached T#6.5.
[6] Aivu ultimately made landfall between Home Hill and Inkerman at 0300 UTC (1:00 p.m. AEST) with a pressure of 957 mbar (hPa; 28.26 inHg).
[6] Rapid weakening ensued as Aivu moved inland; the JTWC estimated winds to have dropped to 100 km/h (65 mph) within six hours of landfall.
[8] On 3 April, a leading supermarket in Ayr reported a major increase in daily sales from A$16,000 to A$60,000, indicating that residents were taking appropriate actions to prepare for Aivu.
[9] Early in the storm's existence, it brought heavy rains to the eastern islands of Papua New Guinea, causing major flooding.
Jacob Lemeki, a member of the National Parliament, and several others went missing after two vessels disappeared in the storm near the Louisiade Archipelago.
[10] A powerful storm, hurricane-force winds with gusts up to 200 km/h (120 mph) are believed to have impacted areas that experienced the eyewall along the immediate coast.
While many areas received more than 200 mm (7.9 in), orographic lift along the Clarke Range about 30 km (19 mi) inland greatly enhanced rainfall totals.
Exceptionally heavy rains fell west of Mackay with a maximum of 1,082 mm (42.6 in) recorded in Dalrymple Heights (located 200 km (120 mi) south of Aivu's track).
Ayr, where Aivu's eye made landfall, experienced a peak hourly rainfall of 71 mm (2.8 in), though this was considered normal for fast moving, intense cyclones.
[14] Severe damage to power lines left many areas without electricity, most notably Burdekin where repairs were expected to take up to two weeks.
Alongside flooding in the days preceding the cyclone, nearly 80 percent of cotton and virtually all vegetable crops in Queensland and New South Wales were damaged or destroyed.
In response, 140 personnel from Delta Company of the Australian Army were dispatched as Defense Aid to the Civil Community by the afternoon of 4 April.
[15] On 7 April, a Cessna aircraft carrying five people crashed in the remote Cravens Peak cattle station near the Queensland–Northern Territory border.
[25] Meanwhile, in Eungella, New South Wales, food, water, and medical supplies had to be airlifted by a RAAF Bell UH-1 Iroquois helicopter because it was inaccessible by ground.
The Department of Primary Industries monitored all crops affected by the storm for signs of a Sclerotinia outbreak and preemptively sprayed them to prevent the disease.