This is a huge hurricane/typhoon heading quickly, and imminently, towards taiwan.
The storm itself is roughly as wide as the island nation is long, so very little will be left unaffected.
The storm is at the very high end of the range of storms in size, strength, etc. It is currently equivalent to a Category 5 hurricane. It may weaken a bit before landfall over the next few hours, but it may remain a Category 5.
Winds, huge waves and coastal flooding from storm surges will be a big problem with this storm, but the largest problem may be the incredibly high rainfall, with about one meter of rain (3 feet) predicted in some locations. This could cause unprecedented and major flooding.
Nepartak should be regarded as a global warming enhanced storm. The storm is made so large and strong because of extraordinarily high sea surface temperatures, which in turn is an effect of human caused global warming.
Locally, the Green Island and the Taiwanese city of Taitung City are on or very close to the expected storm track. If the storm tracks a bit south, expect very severe storm surges in Taitun city. Either way, there will be major rainfall in the river basins, and the valley ousee north of Taitung City, which has several settlements in it, seems likely to be at major risk.
Here is the most current (10:34 AM CT) map from Weather Underground showing the relationship between the storm and Taiwan.
Climate Signals has info on the storm, and does a good job at evaluating the likely relationship between the storm and human caused climate change.
On July 4 and 5, in just 24 hours, cyclone Nepartak intensified from a 70 mph storm to a Category 4 super typhoon with 150 mph winds, peaking with 1-minute sustained winds of 173 mph (150 knots) on July 6. Currently a Category 5 storm, Nepartak is forecast to strike Taiwan Thursday night, July 7, local time (midday Eastern time) before moving on to eastern China. The rapid intensification of Nepartak was driven by favorable climate conditions, including passage over unusually warm seas with some of the highest oceanic heat content readings observed in conjunction with a tropical cyclone. There is a documented increase in the intensity of the strongest storms in several ocean basins in recent decades, including the Pacific Northwest. And warming seas are offering more energy to passing storms. Extreme rainfall over Taiwan is expected to be intense, fueled in part by a warmer atmosphere, with total rainfall in some areas reaching well above 3 feet. The reach of Nepartak’s storm surge will be extended due to elevated sea levels driven up by global warming.
Jeff Masters is covering the storm here. He discusses the very rapid development of this storm:
Category 5 Super Typhoon Nepartak is steaming towards a Thursday landfall in Taiwan after putting on a phenomenal display of rapid intensification on Monday and Tuesday. Nepartak went from a tropical storm with 70 mph winds on Monday afternoon to a Category 4 super typhoon with 150 mph winds on Tuesday afternoon, in just 24 hours.