After indirectly bringing historically rare wildfires to Hawaii, Hurricane Dora rushed all the way into the northwestern Pacific Ocean and became Typhoon Dora. The International Date Line is located on the 180° meridian in the Pacific Ocean, separating two calendar days and marking the dividing line between the Central Pacific and the Western Pacific. On Friday night, Dora crossed the International Date Line from the Central Pacific, becoming the first hurricane to move from the eastern Pacific to the western Pacific since Hurricane Hector's Hurricane in 2018, and the second tropical system on record to maintain hurricane intensity in the eastern, central, and western Pacific, a feat accomplished by Hurricane John in 1994, which was also the longest tropical cyclone in the Pacific.
Hurricane Dora was a tropical cyclone marathon, the earliest embryo of which was a tropical disturbance off the coast of West Africa on July 17, a thunderstorm cloud that had no chance of developing due to dry air and wind shear as it passed through the Atlantic Ocean, and after moving southward through Central America on July 28-29, the system became stronger and more organized as it entered the eastern Pacific Ocean, and strengthened into a tropical depression on July 31, by which time it had traveled more than 7,000 kilometers. After that, Dora became more explosive, and the core area of Dora was very small, compared with the active typhoon Kanu at the same time, the size of the cloud mud was different, and the cloud system range was only 1/5 of Kanu.
However, precisely because the range is not large and conducive to energy concentration, and the sea surface temperature that Dora travels is basically above 26°C suitable for tropical cyclones to survive, and after three weakening after August 4, three times strengthening into Category 4 hurricanes, in general, hurricanes in the eastern Pacific are difficult to survive in the westward direction, because ocean currents usually carry cooler waters south of the California coast and then southwest to the eastern Hawaiian Ocean, which usually has drier air. Vertical wind shear that weakens and tears tropical cyclones typically strengthens closer to Hawaii as well. However, when Dora reached the intensity of a Category 4 hurricane, it gradually developed itself into a tropical cyclone similar in shape to a ring hurricane, a doughnut-shaped tropical cyclone without peripheral rain belts that is generally considered more conducive to maintaining intensity in harsh environments, and its Category 4 hurricane intensity reached 122 hours, surpassing the 96-hour Pacific record of Hurricane Hector's 2018 hurricane, and traveling a route of more than 3,500 kilometers.
The ultra-strong high pressure that directly caused the Hawaiian wildfires is another factor in Dora's continued westward movement, and the developing eastern El Niño and Pacific negative meridional modes may have contributed to this anomalous westward path in terms of broader climate.
Dora takes on the form of a circular hurricane
Dora, currently east of Wake Island, is moving rapidly westward along the high-pressure ridge, but after entering the northwest Pacific, Dora will encounter the mid-ocean trough, which will cause Dora to end its westward northward movement, and the numerical value predicts that it will turn north near 169E, and Dora is expected to weaken rapidly due to the influence of vertical wind shear. It's hard to break the record record of 164.7E at the West Pole after Hurricane Genevieve entered the Northwest Pacific in 2014, but by this time Dora had run more than 9,000 kilometers since the Eastern Pacific number, making it the best typhoon marathon.
Of course, this is not the only tropical cyclone currently active in the northwest Pacific, although the ultra-long standby typhoon Kanu has made landfall in South Korea, another typhoon Rann is eyeing Japan, this typhoon originally regarded as Kanu path disruptor has developed beyond expectations, once strengthened into a super typhoon, and is now weakened to a Category 14 strong typhoon with giant eyes after eye wall replacement, which is expected to hit the Kii Peninsula-Osaka and other places head-on around August 15 (next Tuesday).