After steadily strengthening offshore to a Category 4 system, Debbie eventually made landfall near Airlie Beach, at 12:40 AEST on 28 March.

[2] On 22 March 2017, a well-defined but weak area of low pressure developed over the Coral Sea, near the Louisiade Archipelago of Papua New Guinea.

This prompted the United States-based Joint Typhoon Warning Center (JTWC) to issue a Tropical Cyclone Formation Alert, indicating the system was likely to acquire gale-force winds within 24 hours.

With exceptionally favourable environmental conditions ahead of the storm, the agency noted a high probability for rapid deepening before landfall in Queensland.

After attaining that strength, Debbie assumed a generally southwestwards track—a track it would maintain, with minor fluctuations, until about 14 hours after landfall.

Debbie passed over the Whitsunday Islands in the morning of 28 March local time with winds of 165 km/h (103 mph), still at Category 4 intensity.

[1] The tropical low then executed a long turn to the southeast, and proceeded towards South East Queensland, moving roughly parallel to the coast.

[1] The remnants of Debbie brought heavy rainfall—torrential rains in many areas—that resulted in flooding in large parts of the land areas across which it tracked, before moving out over the Pacific Ocean on Friday 31 March.

[14] A total of 1,000 emergency personnel and more than 200 Energex workers were deployed to the region to assist with Ergon Energy's preparations and clean up operations.

[16] The Royal Australian Navy landing ship HMAS Choules set sail from Sydney to Queensland to support post-storm recovery.

[19] The Australian Defence Force's pre-deployment of resources was the largest in the nation's history in advance of a natural disaster;[13] approximately 1,200 personnel were deployed.

[21] Former Deputy Leader of Australian Greens, Adam Bandt, was criticised by the conservative government's Federal Energy Minister for suggesting that construction of new coal plants would cause climate change, and hence increase the intensity of extreme weather events like Cyclone Debbie.

An unexpected turn to the south during the cyclone's final approach to the Queensland coast brought the storm directly on top of Hamilton Island, where no evacuations took place.

One particular bird, later nicknamed Debbie, was found stripped of its feathers by Townsville Bulletin photographer Alix Sweeney and rescued as the cyclone's eye passed through.

[31][32] Inclement weather and evacuations associated with the cyclone were blamed for a fatal car accident near Proserpine on 27 March, where one person died on-scene whilst two others were hospitalised.

[37] The ex-tropical cyclone went on to cause damage further south, particularly around the Logan and Albert Rivers, flooding infrastructure such as the Beenleigh railway station and resulting in the death of a 77-year-old man in Eagleby.

[43] This triggered heavy rainfall in the Northern Rivers and led to significant flooding in the Tweed, Lismore, Byron, Richmond Valley, Kyogle and Ballina local government areas.