The second typhoon in one week is swirling its way northward in the East China Sea, packing maximum sustained winds of 140 mph as of Tuesday morning Eastern time. The storm peaked early Tuesday with 145-mph winds, becoming the strongest typhoon of the year so far.

Typhoon Maysak will come off its peak and is forecast to make landfall in South Korea on Wednesday, passing to the east of the island of Jeju to come ashore between Busan and Goheung as a strong Category 1 or Category 2 storm.

If it makes landfall as a Category 2 storm, then Typhoon Maysak will be the sixth storm to hit South Korea at such a high intensity. In fact, there are indications this could be one of the strongest storms on record for the country. Based on its track, the storm will have relatively limited time moving over cooler waters and won’t be exposed to strong upper-level winds for very long, lowering the chances South Korea will avoid seeing a particularly powerful storm.

The storm’s track and intensity forecast is concerning, given that it would place Busan in the right front quadrant of the storm, which typically contains the strongest winds and worst storm-surge flood threat. With a population of 3.4 million, Busan is South Korea’s second-largest city and the world’s sixth-largest container port.

In addition, heavy rain poses a significant flood risk in South Korea right now following an unusually lengthy and heavy monsoon season, plus the recent rains from Typhoon Bavi last week. All the preceding rains mean additional rainfall from Maysak, even if it is relatively modest, could cause major flooding. With a forecast track north-northwestward into North Korea and East China, the storm will extend the flood threat farther north, as well.

Computer models show that Maysak, which is currently the equivalent of a Category 4 storm, could come ashore with the lowest air-pressure reading on record for any typhoon in South Korea. That record, according to meteorologist Bob Henson writing for Yale Climate Connections, stands at 950 millibars, which was recorded on Jeju Island during Typhoon Maemi on Sept. 12, 2003.

“Severe impacts from Meimi included 117 deaths, $4.8 billion in damage (USD 2003), some 5,000 homes destroyed, and widespread crop damages,” Henson wrote. “The only other comparable typhoon to strike the South Korea mainland, Sarah (1959), also made landfall just west of Busan. Sarah’s impacts were catastrophic, including at least 669 deaths and 14,000 destroyed homes.”

Typhoon Maysak has already caused damage when it lashed the Japanese islands of Okinawa and Kumejima, where storm chaser James Reynolds captured the fury of the storm. Winds gusted to at least 101 mph on Okinawa, and 120 mph on Kumejima.

Next up: Typhoon Haishen

According to Sayaka Mori, a meteorologist for NHK World, the Korean Peninsula typically sees one land-falling storm per year, based on data since 1951. However, Maysak would be the fourth storm to strike so far this year in an otherwise quiet Western Pacific typhoon season. “This would tie the record number of landfalls” for the Korean Peninsula, Mori tweeted. Yet this is not the only storm out there that could threaten Korea and Japan.

A developing typhoon is located to the southeast of Typhoon Maysak, and is expected to become Typhoon Haishen in the next 24 hours. This storm is forecast to become quite intense, possibly intensifying to the equivalent of a Category 4 storm or higher, as it moves toward southwestern Japan during the next several days.

Thanks to a blocking area of high pressure over the northwestern Pacific, Korea is in the possible path of the storm after it impacts Japan.

Some computer models intensify Haishen into a super typhoon that maintains a high intensity as it closes in on Japan and Korea.

As NHK’s Mori notes, the Western Pacific waters near and to the south of Japan, where Typhoon Maysak traversed and where developing Typhoon Haishen is projected to intensify, are at their warmest levels on record since such data began in 1982, with temperature anomalies of up to 4 degrees above average.