03 Feb 2021 | 01:02 AM UTC
Australia: Tropical Disturbance 18S tracks in southwest direction in coastal Western as of Feb. 3 /update 4
Tropical Disturbance 18S tracking southwestward across coastal Western Australia, Australia, as of Feb. 3.
Event
Tropical Disturbance 18S continues to track southwestward across coastal Western Australia as of Feb. 3. As of 0200 AWST, the storm's center of circulation was approximately 215 km (134 miles) south of Learmonth. Forecast models indicate the system is forecast to strengthen to a Category-1 Tropical Cyclone by Feb. 5 after reentering the Indian Ocean. The system is forecast to maintain a southwestward trajectory, weaken into a tropical low, and continue tracking close to Western Australia coastline through at least Feb. 7. Some uncertainty remains in the track and intensity forecast, and changes could occur over the coming days.
Government Advisories
The Australian Bureau of Meteorology (BOM) has forecast heavy rain and winds in Gascoyne and Pilbara. Authorities are also maintaining flood warnings for river catchments in Kimberley, Pilbara, and Gascoyne.
Authorities will likely issue new warnings or update existing advisories throughout the system's progression in the coming days. Weather warnings could remain active even after the system's immediate threat has diminished, as some areas may still be highly susceptible to rain-induced hazards. The possibility of localized evacuations cannot be discounted if weather conditions prove particularly hazardous.
Hazardous Conditions
Tropical Disturbance 18S will continue to bring heavy rainfall, strong winds, and rough seas to coastal areas along western Western Australia over the coming days. Sustained heavy rainfall could trigger flooding in low-lying communities near streams, creeks, and rivers, as well as in urban areas with easily overwhelmed or a lack of stormwater drainage systems. Sites located downstream of large reservoirs could experience flash flooding after relatively short periods of intense rainfall. Flooding could isolate some communities for several days. Prolonged swells and storm surge generated by the system will likely result in coastal flooding as the system tracks close to land. Persistent onshore flow could make it difficult for the surge to recede and for water levels to decrease in coastal river catchments.
In addition to the heavy rain, flooding, and storm surge, damaging wind gusts will persist. Widespread and prolonged power outages due to uprooted trees and toppled utility lines are possible.
Transport
In addition to the immediate threat to personal safety, inclement weather associated with the storm could trigger localized business, transport, and utility disruptions through at least Feb. 7. Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Areal flooding in urban locations could also result in severe traffic congestion, while strong winds will pose a hazard to high-profile vehicles. Heavy rain and low visibility may trigger flight disruptions at airports.
Disruptions triggered by inclement weather and resultant hazards, such as flooding, could persist well after conditions have improved. If there is severe damage to infrastructure, repair or reconstruction efforts may exacerbate residual disruptions.
Advice
Activate contingency plans in areas where officials forecast tropical storm conditions. Heed all evacuation orders. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the high potential for severe flooding and storm surge. Stockpile water, batteries, and other essentials in advance. Charge battery-powered devices when electricity is available; restrict the use of cellular phones to emergencies only. Power down mobile devices when not in use. Keep important documents in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks. Keep any necessary medications in a waterproof container.
Plan accordingly for protracted commercial, transport, and logistics disruptions in areas in the path of the storm, especially if vital infrastructure is damaged. Seek updated information on road conditions before driving or routing shipments through areas where flooding has occurred. Confirm flights before checking out of hotels or driving to the airport; clearing passenger backlogs may take several days in some locations.
