Philippine Sea: Typhoon Hinnamnor tracking northward in the Philippine Sea evening Sept. 3 /update 6

Event

Typhoon Hinnamnor is tracking northward over the Philippine Sea the evening of Sept. 3. As of 18:00 JST, the system's center of circulation was approximately 440 km (274 miles) southwest of Kadena Airbase, Okinawa Prefecture, Japan.

Forecast models indicate that the storm is forecast to make a close approach to the Yaeyama Islands late Sept. 3 before strengthening as it continues to track northward then north-northeastward in the East China Sea Sept. 4, before weakening as it turns to track northeastward as it passes eastern mainland China Sept. 5. The storm is likely to weaken further as it continues to track northeastward towards the Korean Straight, making a close approach to Jeju Island, South Korea, late Sept. 5 before making landfall over the southwestern coast of South Gyeongsang Province early Sept. 6. The system is forecast to weaken to an extratropical cyclone as it tracks northeastward across the southwestern tip of the Korean Peninsula Sept. 6 before exiting into the Sea of Japan off the southern coast of North Gyeongsang Province. The storm is likely to weaken into a tropical storm as it makes a close approach to Primorsky Krai, Russia, the afternoon of Sept. 7. Some uncertainty remains in the track and intensity forecast, and significant changes could occur in the coming days.

The Japan Meteorological Agency (JMA) has warned of strong winds, rough seas, heavy rainfall, and thunderstorms over parts of Okinawa Prefecture through at least Sept. 4. Waves of around 10 meters (23 feet) in height are forecast in the Okinawa region and around 7 meters (23 feet) in the Amami region Sept. 4. Storm surge is possible in parts of Okinawa Prefecture through Sept. 4. Rainfall amounts of around 25 cm (10 inches) in Okinawa region, 20 cm (8 inches) in Tokai region, 18 cm (7 inches) in southern Kyushu, and lesser rainfall amounts across the rest of western Japan. Heavy rainfall associated with the storm system and other meteorological disturbances is also forecast across parts of western and eastern Japan through Sept. 4.

As of the evening of Sept. 3, the JMA has issued purple storm surge warnings (highest level on a three-tier scale) across the Yaeyama and Miyako islands. Red storm and high wave warnings are in place across most of Okinawa Prefecture. Further weather warnings with a varying degree of association with the storm system have been issued across parts of the rest of Japan. Purple heavy rainfall and landslide warnings have been issued for western Kagoshima, southern Mie, northeastern Miyazaki, and northern Nara prefectures.

Taiwan's Central Weather Bureau has issued a sea and land typhoon warning for the storm. Orange extremely heavy rain advisories (the second lowest level on a four-tier scale) have been issued for Hsinchu, Miaoli, and Yilan counties as well as Keelung, New Tapei, Taoyuan, and Tapei cities. Yellow heavy rain advisories are in place across the rest of northern and northwestern Taiwan.

The China Meteorological Administration has issued a yellow level typhoon warning (the second lowest level on a four-tier scale); heavy rainfall is forecast across northeastern Zhejiang Provinces while strong winds are likely in the East China Sea and surrounding coastal waters.

The Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) has warned of light to moderate heavy rainfall over Batanes Province and Babuyan Islands Sept. 3. Authorities have issued Tropical Cyclone Wind Signal No. 1 (level 1 out of 5) for Batanes Province and the northeastern Babuyan Islands.

Officials will likely update and extend the coverage of the relevant weather alerts over the coming days as the system progresses.

Japan Airlines (JL) has canceled all flights at Kikai (KKX), Tokunoshima (TKN), Okinoerabu (OKE), Yoron (RNJ), Kumejima (UEO), Okinawa Naha (OKA), Miyako (MMY), Tarama (TRA), Yonaguni (OGN), New Ishigaki (ISG), and Shimojishima (SHI) airports Sept. 3 and at Kikai (KKX), Amami (ASJ), Tokunoshima (TKN), Okinoerabu (OKE), Yoron (RNJ), Kumejima (UEO), and Shimojishima (SHI) airports Sept. 4. Japan Airlines has also canceled some flights at Okinawa Naha Airport (OKA) Sept. 4.

All Nippon Airways (NH) has also canceled all flights at Miyako (MMY) and New Ishigaki (ISG) airports Sept. 3 and some flights at Okinawa Naha (OKA) Sept. 3 and at Okinawa Naha (OKA), Miyako (MMY), and New Ishigaki (ISG) airports Sept. 4. Further flight cancellations are likely as the storm progresses.

Authorities have issued evacuation orders for portions of Okinawa, Mie, Niigata, Kagoshima, and Kyoto prefectures due to the typhoon and associated severe weather.

Sustained heavy rainfall could trigger flooding in low-lying areas and those with easily overwhelmed drainage systems. Localized evacuations, flash flooding, and landslides are possible if weather conditions prove hazardous.

The inclement weather could trigger localized business, transport, and utility disruptions, rendering some bridges or roadways impassable. Flight disruptions at regional airports and temporary closures of ports are also possible. Raw sewage and other hazardous materials mixed with floodwaters pose a serious health threat.

Advice

Activate contingency plans in areas where officials forecast typhoon or tropical storm conditions. Heed any evacuation orders that may be issued. Use extreme caution in low-lying coastal areas and near streams, creeks, and other waterways due to the 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 and necessary medications 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.

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.

Resources

Joint Typhoon Warning Center
Japan Meteorological Agency
Taiwan Central Weather Bureau
China Meteorological Administration
Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA)
Korea Meteorological Administration