Summary
An active monsoon trough to the north of Western Australia produced a number of transient low pressure systems during mid-December 2013. A discrete centre within this broad circulation formed late on 25 December and moved southwest. The low developed slowly and did not reach tropical cyclone strength until 0600 UTC (Universal Time Coordinated) 28 December (1400 WST = UTC + 8 hours).
Christine steadily intensified while continuing on a south to southwest track, reaching Category 3 severe tropical cyclone intensity at 1800 UTC 29 December. A feature of the tropical cyclone was its large size, with gale force winds and heavy rainfall well away from the centre. Severe Tropical Cyclone Christine crossed the Pilbara coast as a Category 4 cyclone with a peak intensity of 90 knots between Roebourne and Whim Creek around 1500 UTC 30 December. As Christine crossed the coast a very destructive wind gust of 93 knots (kn) (172 kilometres/hour (km/hr)) was recorded at Roebourne Airport. Other notable wind gusts were 72 knots (133 km/h) at Karratha and 70 knots (130 km/h) at Port Hedland.
Christine began weakening once it crossed the coast and accelerated to the southeast. Christine maintained its tropical cyclone structure further inland than most tropical cyclones and was downgraded to below tropical cyclone strength at 1200 UTC 31 December. After weakening below tropical cyclone intensity, the low pressure system moved quickly across southeast WA, producing damaging winds and moderate to heavy rainfall.
Heavy rainfall was recorded in the vicinity of the cyclone path, with the heaviest 24 hour fall being 168 mm at Abydos North; a rain gauge to the southeast of Port Hedland. Other notable 24 hour falls were 134 mm at Roebourne airport, 123 mm at Port Hedland and 113 mm at Karratha. There was minor to moderate flooding in Pilbara river catchments, particularly of the De Grey River.
For more information see the TC Christine Report (pdf).
Track and Intensity NT
