21 Jun 2021 | 11:08 AM UTC
North Pacific: TD 06W continues tracking northwestward over North Pacific Ocean near Guam late June 21
TD 06W continues tracking northwestward over North Pacific Ocean near Guam late June 21. Disruptions likely.
Event
Tropical Depression (TD) 06W continues to track northwestward across the North Pacific Ocean, late June 21. As of 19:00 ChST, the system's center of circulation was approximately 257 km (160 miles) southeast of Anderson Air Force Base, Guam. Forecast models indicate the system will continue tracking northwestward and strengthen slightly into a tropical storm as it makes a close approach to Guam, early June 22. The storm is then forecast to enter the Philippine Sea the same day, strengthening further and turning to track northwards through at least June 26. The system will start to weaken late June 24 and is forecast to dissipate south of Honshu, Japan, late June 26 without making landfall. Some uncertainty remains in the track and intensity forecast, and changes could occur over the next few days.
Government Advisories
As of 16:00 ChST June 21, the US National Weather Service has issued the following warnings:
High Surf Advisory: East and south facing reefs of the Marianas; hazardous surf of 3-4 meters (9-12 feet) is possible
Flash Flood Watch: Rota, Guam, Tinian, and Saipan Islands; rainfall of 8-13 cm (3-5 inches) is possible.
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. The possibility of localized evacuations remains if weather conditions prove particularly hazardous.
Hazardous Conditions
TD 06W is forecast to produce rounds of heavy rainfall across portions of the southern Mariana Islands over the coming days. Sustained heavy rainfall could trigger flooding in low-lying communities near streams, creeks, rivers, and urban areas with easily overwhelmed stormwater drainage systems. Sites located downstream of reservoirs could experience flash flooding after relatively short periods of intense rainfall. Flooding could isolate some communities for several days.
Persistent onshore flow could make it difficult for surges to recede and for water levels to decrease in coastal river catchments. In addition to the heavy rain, flooding, and storm surge, the storm could produce damaging wind gusts, resulting in widespread and prolonged power outages due to uprooted trees and toppled utility lines.
Transport
In addition to the immediate threat to personal safety, inclement weather associated with the storm could trigger localized business, transport, and utility disruptions through at least June 23. Floodwaters and debris flows may render some bridges 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.
Advice
Activate contingency plans in areas where officials forecast tropical storm conditions. Heed all evacuation orders. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the high potential for severe flooding and 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. Keep important documents in waterproof containers. Observe strict food and water precautions, as municipalities could issue boil-water advisories following flooding events. Take precautions against insect- and waterborne diseases in the coming weeks. Keep any necessary medications in a waterproof container.
Plan accordingly for protracted 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.
