Australia: Severe weather forecast over parts of central Northern Territory through at least March 21

Severe weather is forecast across parts of central Northern Territory through at least March 21. The remnants of Cyclone Megan are expected to move westward over the affected area March 20-21, bringing heavy rainfall and strong winds, especially along the southern flank of the storm system.

As of March 20, the Australian Bureau of Meteorology (BOM) has issued a severe weather warning for damaging winds and heavy rainfall across parts of Barkly, Simpson, and Tanami forecast districts. Locations that may be affected include Tennant Creek, Elliott, Ali Curung, Rabbit Flat, Barrow Creek, and Renner Springs. Heavy rainfall, which may lead to possible flash flooding, is expected in parts of western Barkly Disttrcict from March 20 before extending into parts of Tanami and northwestern Simpson districts overnight March 20-21; six-hourly rainfall totals of 5-8 cm (2-3 inches) and 24-hourly totals of up to 18 cm (7 inches) are possible in the affected areas. Winds gusting up to 90 kph (56 mph) are also possible in the warning area before easing through March 21. Flood watches are in place across the affected area. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming hours and 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.