Cyclone Chapala is tracking west through the Arabian Sea, targeting Yemen as the first hurricane-strength storm to make landfall there since records began. While the storm’s winds will certainly pack a punch as the storm comes ashore in the early morning hours Tuesday, its rainfall may prove deadly — the cyclone is forecast to dump at least five years’ worth of rain over the mountains near the vulnerable port city of Al Mukalla.
Chapala has benefited from extremely warm water in the Arabian Sea, maintaining its strength as the equivalent of a Category 3 hurricane, after peaking as a strong Category 4 on Friday. The storm has generated more energy than any other tropical cyclone on record in the Arabian Sea.
Honing in on the southern Arabian Peninsula, Chapala is packing winds of 120 mph, with gusts up to 150 mph. Wave heights around the storm are 30 feet.
Since Friday, Chapala’s track shifted south, putting Yemen — and the vulnerable port city of Al Mukalla — squarely in its path. Chapala is forecast to make landfall as a Category 1 or 2 storm about 50 miles southwest of Al Mukalla around 3 a.m. Yemen time, placing residents at even higher risk as they endure hurricane-force impacts in the dark, early morning hours.
After landfall, Chapala will rapidly dissipate as it encounters the dry, hostile environment of the Arabian Peninsula. Yemen’s mountainous, desert terrain will act to tear apart the strong storm even faster than Mexico’s mountains obliterated Hurricane Patricia.
But before it dissipates, Chapala will bring extremely heavy rainfall and high waves to a region not accustomed to rain, and zero experience with a storm like this.
Chapala’s winds will certainly be strong as it washes ashore, but its rainfall will be the most life-threatening impact for coastal Yemen. To compare, the precipitable water in the storm, which meteorologists use to measure rainfall potential, is 10 times as high as the precipitable water in western Yemen.
The high-resolution HWRF model suggests Chapala is going to produce up to 30 inches of rain near Al Mukalla. According to the U.K. Met Office, this region typically gets less than 4 inches of rain per year, meaning Chapala will likely bring at least five years’ worth of rain to parts of Yemen.
Combine the inexperience with torrential, tropical cyclone rain with the region’s mountains and lack of vegetation and you have a recipe for a deadly flooding disaster on the Yemen coast.
Cyclones themselves are not uncommon in the Arabian Sea — on average a few weak to moderately strong storms spin up each year. However, cyclone landfalls in this region are rare.
Chapala will be the first known hurricane-strength storm to make landfall in Yemen since modern records began there in the 1940s. And if Chapala maintains hurricane strength at landfall, it would only be the third hurricane on record to make landfall on the entire Arabian Peninsula.
The only other tropical cyclone to make landfall in Yemen in the satellite record, which goes back to 1990, was a tropical depression in 2008. That storm, which was far weaker than Chapala will be at landfall, led to disastrous flooding, reports Weather Underground’s Jeff Masters. The depression caused over $400 million in damage and killed 90 people. It was the second worst natural disaster in Yemen history, though it will likely get bumped down the list after Chapala makes landfall.
— WMO | OMM (@WMOnews) November 2, 2015
Tropical cyclones are known as just “cyclones” in the Indian Ocean, but they’re the same kind of storm as typhoons or hurricanes. The Indian Meteorological Department is responsible for tropical cyclone warnings in the North Indian Ocean.