Wildfish Media — Typhoon and Travel Weather in Asia

Hue gets 17.2 inches of rain in October. Da Nang gets 17.9. Hoi An gets 17.5. Three cities, ninety kilometres apart end to end, and in the month that matters they are the same place. That is the first thing to understand about central Vietnam in October: there is no drier alternative a short drive away. Whatever October does, it does to all of it. Two thirds of the year in three months This site has already laid out why Vietnam has three rain regimes rather than one , and why the central coast is dry in July while Hanoi is soaked. This page is about what happens at the other end of that inversion, when the central coast collects a year's worth of weather in a single quarter. The numbers below are the three central cities side by side. Every figure is a monthly average from the same source, so they are directly comparable. Month Hue Da Nang Hoi An July 2.5″ 2.3″ 2.3″ August 4.9″ 4.7″ 4.6″ September 11.5″ 11.5″ 11.1″ October ...

Haima and Nock-ten. Khanun and Tembin. Kammuri and Phanfone. Molave, Goni and Vamco. Kompasu and Rai. Nalgae. Yinxing. Fengshen and Kalmaegi. Fifteen storms, and every one of them came within 100 km of a major Philippine city in October, November or December. That is the last ten seasons, counted from the Japan Meteorological Agency's own track archive, and it is the part of the Philippine year that almost every English-language travel guide treats as the tail end of something. The season does not wind down. It relocates The common picture of the western Pacific typhoon season has it building through the summer, peaking in August, and fading through autumn. For Japan, Korea, Taiwan and Okinawa that picture is roughly right. For the Philippines it is wrong in a way that puts people in the country at exactly the wrong time. The reason is steering, not storm production. Systems form in much the same part of the ocean all season. What changes is the pattern that carries them west....

Vietnam is roughly 1,650 kilometres from top to bottom, which is about the distance from London to Athens, and almost every article about its rainy season treats it as one country with one wet season. That single mistake is responsible for most of the ruined trips. The country has three rain regimes, and two of them are close to opposite. There is a month in which the driest of the three cities below is the one that will be underwater eleven weeks later. If you take one thing from this page, take that: in Vietnam, the answer to when it rains is meaningless until you say where. Image: NASA Worldview (public domain) The figures below are monthly averages from Weather Spark, taken from the same source for all three cities so that they can actually be compared. A great many published comparisons quietly mix stations and periods, which is how you end up with tables that contradict each other. The north: Hanoi and the summer monsoon Hanoi runs on the classic southwest monsoon. Rain arri...