Australia: Severe weather forecast over parts of southeastern Western Australia through at least March 13

Severe weather is forecast across parts of southeastern Western Australia through at least March 13. A near-stationary trough will combine with tropical moisture drawn southward into the region to generate heavy rainfall with embedded thunderstorms across the affected area over the coming days. As of March 11, the Australian Bureau of Meteorology (BOM) has issued a severe weather warning for heavy and locally intense rainfall across parts of Goldfields, Eucla, and South Interior forecast districts. Locations that may be affected include Carnegie, Cocklebiddy, Eyre, and Rawlinna.

Six-hourly rainfall totals of 3-6 cm (1.2-2.4 inches) with 24-hour totals of up to 9 cm (3.5 cm) are forecast over parts of eastern Goldfields, central Eucla, and southern South Interior districts late March 11-12. Heavier downpours with embedded thunderstorms are possible in parts of the affected area, bringing six-hourly rainfall totals of around 8 cm (3.1 inches) and 24-hour totals of 11-13 cm (4.3-5.1 inches) in places. Severe downpours could trigger flash flooding in affected areas. Flood watches and warnings are in place for several river catchments across southeastern WA. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming hours and days.

Heavy rainfall in the region is causing transport-related disruptions as of March 11. Floodwaters have blocked sections of both the Trans-Australian Railway line and the Eyre Highway, which are the main rail and road links into WA from South Australia. Flooding has also cut the highway between Laverton and Leonora. Closures are expected to last for several days.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed or a lack of stormwater drainage systems. Sites downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rain has saturated the soil.

Floodwaters and debris flows may render further bridges or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Flooding could block regional rail lines; freight and passenger train delays and cancellations are possible in areas with heavy rainfall and potential track inundation. Severe weather could also trigger flight delays and cancellations at regional airports.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and employees' inability to reach work sites. Electricity and telecommunications service disruptions are possible where significant flooding, strong winds, or landslides impact utility networks.