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Severe Tropical Cyclone Marcia was a powerful tropical cyclone that made landfall at its peak strength over central Queensland, near Shoalwater Bay on 20 February 2015. The cyclone went on to affect various areas including Yeppoon and Rockhampton. It passed just to the west of Yeppoon as a Category 5 system, then traversed over the regional city of Rockhampton as a Category 3 system on the same day. Eventually, the cyclone weakened, moved southeast out to sea, before dissipating. Marcia caused at least A$750 million (US$587 million) worth of damage.
When Marcia intensified into a category 2 tropical cyclone at 00:00 UTC on 19 February, it had developed a central dense overcast with a consolidating eyewall because of weakening vertical wind shear. Thanks to very good poleward outflow into the westerlies, Marcia dramatically underwent Rapid deepening and formed a clear eye, becoming a category 3 severe tropical cyclone at 05:00 UTC and a category 4 system at 08:00 UTC. Soon afterwards, it turned southwards along the western periphery of a subtropical ridge and reached peak intensity at 18:00 UTC as a category 5 severe tropical cyclone with 10-minute maximum sustained winds at 205 km/h (125 mph), featuring a very well-defined 35 km (20 miles) eye. Maintaining strength, Marcia made landfall over the coast near Shoalwater Bay at 22:00 UTC (08:00 AEST on 20 February).
On 20 February, despite good poleward outflow, Marcia began to track southeastwards along the western periphery of the subtropical ridge and rapidly weakened due to land interaction and increasing vertical wind shear, yet the JTWC issued the final warning during sunset. The system weakened into a category 3 cyclone at 13:00 AEST (03:00 UTC), lost the severe tropical cyclone intensity at 17:00 AEST (07:00 UTC) and even weakened into a category 1 cyclone at 20:00 AEST (10:00 UTC). The BoM's final technical bulletin of Marcia indicated that the cyclone had eventually weakened into a tropical low at 15:00 UTC (01:00 AEST on 21 February), with the asymmetric wind structure and unimpressive observations.
The ex-tropical cyclone arrived in the Coral Sea from the southeast coast of Queensland on 21 February. The JTWC monitored Marcia again on 22 February and claimed that the system had become subtropical with Beaufort scale sustained winds, when sea surface temperature (SST) was approximately 25 °C; moreover, satellite imageries also revealed a broad, exposed low-level circulation centre (LLCC) with deep convection displaced over the southeast periphery of the LLCC. Although it drifted northwards over warmer SST later, it was failed to intensify but weakened further. On 27 February, Marcia entered the responsible area of the Fiji Meteorological Service as a weak low-pressure system. The remnants were completely absorbed into a trough on 1 March.
Over 60 000 homes were left without power in Yeppoon, Rockhampton and Bundaberg as the storm moved south. Almost 3000 people requested assistance from the SES – including 800 in central Queensland. Significant structural damage occurred in the Yeppoon area and along the Capricorn Coast, with a number of houses having roofs blown off and walls torn down. Months later, houses are still permanently damaged. Structural damage also occurred across Rockhampton and in the townships of Marmor and Mount Larcom. Heavy rain fell across several regions and authorities evacuated residents from the small town of Jambin, south-west of Rockhampton, as localised flooding took place, which also affected Biloela. Tropical Cyclone Marcia: Gympie businesses begin to flood with water from Mary River Total damage in Queensland reached A$750 million (US$587 million).
The observed windspeeds were lower than the analyzed maximum sustained winds, which had been estimated using the Dvorak technique. The Bureau was criticised for continuing to report the ADT estimates after lower actual windspeeds had been recorded, by biologist and blogger Jennifer Marohasy of Central Queensland University. The International Wind Hazard Damage Assessment Group also expressed concern, saying "A community that receives an over-represented wind speed report may have potential for complacency in preparation or building standards in the future." BOM rejected the criticism, stating that Middle Percy Island was not located in the region of highest windspeed. The equipment there had also been destroyed by the storm, cutting off the data flow. Bureau chief Robb Webb also rejected claims BOM had relied solely on modelling, noting that the bureau worked with the US Joint Typhoon Warning Center to predict the storm's strength. The cyclone is still officially classified by the bureau as a Category 5.
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