It’s October, but the tropics don’t care — at least in the Pacific Ocean where three storm systems are now threats to land on two continents.
Western Pacific: Typhoon Phanfone Strengthens And Another Will Form On Its Heels
Typhoon Phanfone strengthened as it passed Guam on Wednesday and is now a 125 mile-per-hour storm headed for Japan. Phanfone has lived a comfortable life over warm water with little vertical wind shear (change of wind with height: a condition that inhibits tropical storms).
Now it is about to travel over colder water and is already feeling the effects of west winds in the jet stream.
The result will be a weakening storm as it approaches Tokyo, but it still may affect mainland Japan with typhoon-force winds.
Meanwhile, tropical system 19W will become a named storm later today; it will be called Vongfong. Vongfong will follow roughly the same path as Phanfone, and it could reach Super-Typhoon status, though there will be headwinds, literally and figuratively.
The First Threat: Phanfone
Phanfone reached maximum strength overnight and, though the joint Typhoon Warning Center forecasts slight strengthening this morning, that won’t happen.
Satellite imagery shows that the northern edge of the storm is already being degraded by jet stream west winds.
These winds will force the storm to turn sharply to the right, but the path is likely to come within 100 miles of Tokyo on Sunday, at which time Phanfone could still be a minimal typhoon, with winds of 75 miles per hour.
A slight deviation from the predicted path could put Phanfone very close to Tokyo.
The Second Threat: Vongfong
19W will become Tropical Storm Vongfong today — in fact it has already reached the threshold of 39 mile per hour winds as of 5 a.m. EDT.
It will be a typhoon as it passes north of Guam on Monday and accelerates towards Japan.
Vongfong will likely become the equivalent of a major hurricane (winds over 115 miles per hour, and could possibly become a Super -Typhoon (winds over 150 miles per hour) before it is degraded by jet stream winds and colder water.
If there is a wrinkle in the jet stream, Vongfong could strike Japan directly and be more dangerous than Phanfone.
Western Pacific Storm Names
The names of western Pacific tropical systems do not go in alphabetical order as they do in the Atlantic and eastern Pacific. The countries of Asia that could be affected rotate suggested names. In the current case, Phanfone was recommended by Laos, and Vongfong is the suggestion of Macao.
The Philippines insists on having its own names for storms which reach its jurisdiction. That will not happen with Phanfone and Vongfong.
The Eastern Pacific: Yet Another Storm Off The Mexican Coast
The warm waters south of Mexico have produced a long string of Tropical Storms and Hurricanes this season. The latest is Simon. Most have stayed just far enough offshore to spare Mexico any serious effects. However, Hurricane Odile struck the southern tip of Baja California with major hurricane winds and the moisture was carried into the American southwest, where it caused serious flooding.
Though most of the eastern Pacific storms have stayed safely out to sea and dissipated over colder water, jet stream winds are moving farther south as the season progresses. Simon will be nudged closer to the coast by Monday and Tuesday, but its trajectory takes it over colder water and Simon will not affect Baja with any wind.
The moisture from Simon could cause flooding in central Baja and adjacent mainland Mexico. By the middle of next week, Arizona and New Mexico could experience another significant rain event.
What’s Ahead For The Pacific Tropical Storm Season?
Hurricane season in the eastern Pacific runs through Nov. 30. The warm water persists south of Mexico and it would not be a surprise to see more storms on the general path of Simon.
The western Pacific typhoon season extends all year long. The water in the western Pacific is always warm enough for tropical development. Phanfone and Vongfong will likely not be the last storms of the year, and Super-Typhoons are still a possibility well into fall.
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