Weather: TD Laura continues to weaken as it tracks northeast in south-central US, Aug. 28. Transport and utility disruptions present. view alert
- Alert Begins: 28 Aug 2020 10:58 AM UTC
- Alert Expires: 31 Aug 2020 06:00 AM UTC
- Categories: Cyclone
- Incident: Tropical Depression Laura
- Affected Area(s): South-Central, Tennessee Valley, Ohio Valley, Mid-Atlantic, and Northeast regions, US; far eastern Canada (map)
- Time Frame: Through at least Aug. 30
- Center of Circulation: Approximately 155 km (95 miles) west-northwest of Memphis, Tennessee
- Maximum Sustained Winds: 30 knots (55 kph, 35 mph)
Tropical Depression Laura continues to rapidly weaken as it continues moving northeastward across the south-central US, Aug. 28. As of 0400 CDT, the storm's center of circulation was approximately 155 km (95 miles) west-northwest of Memphis, Tennessee. Forecast models indicate the system will continue to weaken as it veers eastward, remaining a tropical depression as it transits the Tennessee Valley, Ohio Valley, Mid-Atlantic, and Northeast regions through Aug. 29. Laura will enter the Atlantic Ocean by late Aug. 29-early Aug. 30. The storm is then forecast to strengthen slightly into a post-tropical cyclone with tropical-storm-force winds off the coast of the Mid-Atlantic region before tracking northeastward toward the Canadian Maritimes through Aug. 31. Laura will make a close approach to Nova Scotia's east coast before making an additional landfall in eastern Newfoundland as a post-tropical cyclone Aug. 30-31; however, the guidance is highly varied, and there is low confidence in the forecast, especially about potential impacts in Canada. Some uncertainty remains in Laura's forecast track and intensity, and changes in projection could occur over the coming days.
As of 0400 CDT Aug. 28, flash flood watches, flood warnings, and flood advisories remain in effect for parts of southern coastal Louisiana, Arkansas, far northern Mississippi, far northwestern Alabama, western Tennessee, far southeastern Missouri, and western Kentucky. 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.
Tropical Depression Laura will likely bring heavy rainfall and strong winds to areas across the South-Central, Ohio Valley, Tennessee Valley, Mid-Atlantic, and Northeast regions of the US through Aug. 30, and possibly the Canadian Maritimes and Newfoundland Aug. 30-31. Forecast models indicate additional rainfall totals of 2.5-7.6 cm (1-3 inches) are forecast across portions of northeastern Arkansas, northern Mississippi, northern Alabama, western and central Tennessee, southeastern Mississippi, and western and central Kentucky. Locally higher totals of up to 12.7 cm (5 inches) are possible in the hardest-hit areas. Additional totals of 2.5-5 cm (1-2 inches) are expected in southern Louisiana, southern Mississippi, southern Alabama, central and southern Appalachians, and Mid-Atlantic states. Locally higher totals of 10 cm (4 inches) are possible in the hardest-hit areas of this region.
Additional sustained heavy rainfall could trigger flooding in low-lying communities near streams, creeks, and rivers, as well as in urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of large reservoirs could experience flash flooding after relatively short periods of intense rainfall. Rain-induced landslides cannot be discounted in steeply sloped terrains. Flooding could isolate some communities for several days.
In addition to the heavy rain and flooding, Tropical Depression Laura will continue to produce damaging wind gusts. Additional widespread and prolonged power outages due to uprooted trees and toppled utility lines are likely. Isolated tornadoes are possible in parts of the affected region over the coming days. Reports indicate over 800,000 customers are without power across portions of Texas, Louisiana, and Arkansas. Additionally, at least six people are reported to have died as a result of the tropical system, all of which are currently in Louisiana.
Inclement weather associated with the storm is likely to trigger ground, air, and maritime transport disruptions in areas along the system's track through Aug. 31. 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 regional 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.
Activate contingency plans in areas where officials forecast tropical storm or other severe weather conditions. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the potential for flooding or 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.
Plan accordingly for 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.