Australia: Adverse weather forecast across parts of Australian Capital Territory, Queensland, and New South Wales through at least Dec. 23

Severe weather is forecast across parts of eastern Australia through at least Dec. 23. Ioslated showers and thunderstorms are forecast across the region over the coming days, with the most severe weather likely in parts of eastern and northern New South Wales (NSW) and into southern Queensland Dec. 19-20 before contracting northward into far northern NSW and southern and south-central Queensland Dec. 21-22. Strong winds, lightning, and hail may accompany storms. Rainfall totals of over 20 cm (8 inches) are possible in parts of northeastern NSW and southeastern Queensland through Dec. 23.

As of Dec. 19, the Australian Bureau of Meteorology (BOM) has issued a severe thunderstorm warning for damaging winds, heavy rainfall, and large hailstones across parts of Hunter, Illawarra, Mid North Coast, South Coast, Central Tablelands, Southern Tablelands, Central West Slopes and Plains, Snowy Mountains, and North West Slopes and Plains Forecast districts in NSW. Marine wind warnings are also in place along parts of the NSW coast Dec. 19-20. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming 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 located 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 some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.

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.