11 Dec 2020 | 10:22 PM UTC
Australia: Forecast heavy rainfall may cause flooding in eastern region through at least Dec. 16
Heavy rainfall, strong winds, and flooding forecast in eastern Australia through at least Dec. 16. Disruptions possible.
Event
A series of storm systems will bring rounds of heavy rainfall to portions of eastern Australia, including southeastern Queensland and the northeast coast of New South Wales (NSW), including the cities of Grafton, Coffs Harbour, and Port Macquarie, through Dec. 16. Forecast models indicate the initial rounds of storms will occur beginning early Dec. 12 and will largely persist in the region over the coming days. The storms will probably be most intense Dec. 14.
The Bureau of Meteorology has issued the following warnings:
Severe Weather Warning (Queensland): Wide Bay and Burnett and Southeast Coast Forecast Districts
Severe Weather Warning (New South Wales): Northern Rivers and Mid North Coast Forecast Districts
Additionally, flood watches and warnings are in effect for various rivers and catchments across Queensland and New South Wales. Officials will likely update and possibly extend the coverage of the relevant weather alerts over the coming days.
Hazardous Conditions
Forecast models indicate rainfall totals of 5-15 cm (2-6 inches) are expected across the hardest-hit areas over the coming days, including the northeastern coast of NSW. Locally higher totals of up to 25 cm (10 inches) are possible. Lower amounts are expected farther south and west in NSW, as in southeastern Queensland. 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 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 cannot be discounted in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall. The storms may also bring rough surf and damaging winds to coastal locations. Disruptions to electricity and telecommunications services are possible where significant flooding, strong winds, or landslides impact utility networks.
Transport
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.
Severe weather could also trigger flight delays and cancellations at regional airports, including those serving Brisbane (BNE) and Gold Coast (OOL). Authorities may temporarily suspend port operations or close beach fronts along the Coral Sea or the Tasman Sea if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation. 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 some employees' inability to reach work sites.
Advice
Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments prior to travel. Make allowances for localized travel delays, as well as potential supply chain disruptions, where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in case prolonged electricity outages occur.
