Published: October 29,2015
Hurricanes in Strange Places
Tropical cyclone tracks from 1851-2006. Track of Hurricane Catarina in March 2004 is circled yellow. (NASA)
But just like anything else in life, there are outliers. Sometimes the atmosphere conspires to either pull a tropical cyclone out of its typical track, or even forms a storm with tropical characteristics in a completely different part of the world.
Up to that time, no hurricane had ever been confirmed in the South Atlantic Ocean. It was thought wind shear, which is the change in wind speed and direction with height, was too strong in this area to allow clusters of thunderstorms to organize around an area of low pressure to begin the process of tropical cyclogenesis.
In late March 2004, however, wind shear was low off the eastern coast of South America as an upper-level low-pressure system was sprouting thunderstorms near its center.
Making the transition to a tropical cyclone, what was later called Hurricane Catarina turned back westward, making landfall in the Santa Catarina province of Brazil as a Category 1 equivalent on March 27, 2004.
According to the final summary by Marcelino et al., just over 38,000 structures were damaged and another 1,468 collapsed. Despite the freak nature of this storm, some residents evacuated from the coast.
Southern California
Map showing the position of the San Diego hurricane on Oct. 2, 1858. (Michael Chenoweth, Christopher Landsea/NOAA)According to a 2012 estimate, the L.A. and San Diego metro areas are home to more than 16 million people.
Thanks to a cold ocean current called the California Current, water temperatures off the California coast typically hold in the 60s. Convection from a tropical storm or hurricane trying to make the voyage northward from the southern Baja California Peninsula would move over these colder waters and fizzle.
But this hasn't always been the case.
A 2004 paper by Michael Chenoweth and Christopher Landsea from NOAA/AOML's Hurricane Research Division combined newspaper accounts with meteorological observations to confirm a hurricane did strike San Diego in October 1858. It was the only hurricane known to have directly impacted Southern California.
Damage in San Diego was found to be consistent with that of a Category 1 hurricane, including homes destroyed and ships driven ashore. If a similar hurricane were to hit Southern California today, damage up to several hundred million dollars would result, according to Chenoweth and Landsea.
On September 25, 1939, a tropical storm made landfall in Long Beach, Calif., with 50 mph winds and torrential rainfall. Over five inches of rain soaked L.A., while over 11 inches soaked Mt. Wilson. Forty-five lives were lost at sea and $2 million damage was done to both structures and crops.
Tropical cyclone remnants are not all that unusual in the Southwest U.S. The most typical impact of these dying systems is flooding rainfall.
Hawaii
Hawaii is America's paradise, with highs in the 80s, plentiful sunshine, showers mainly in the mountains and epic surfing.That said, did you know four hurricanes have tracked within 65 nautical miles of the island chain from 1957-2012?
Hurricane Iniki clobbered the island of Kaua'i as a Category 4 hurricane on Sep. 11, 1992, killing six and costing $3 billion in damage. Iniki remains the state's deadliest hurricane on record.
(MORE: Dr. Rick Knabb Recalls Iniki {written in 2012})
Three of those four hurricanes approached the islands from the south. Thankfully, most tropical cyclones approaching the islands from the east typically weaken to either depressions or low-grade tropical storms, owing to more stable, dry air, and/or cooler water.
Newfoundland
Satellite image of Hurricane Igor sweeping by Newfoundland, Canada on Sep. 21, 2010. (NOAA)Lying largely farther north than Maine, with ocean temperatures in the 60s, you probably wouldn't put "hurricanes" and "Newfoundland" together in a sentence.
However, tropical cyclones in eastern Canada are actually quite common. Roughly two-thirds of hurricane seasons from 1951-2008 featured at least one landfalling tropical storm or hurricane in eastern Canada, according to the Canadian Hurricane Centre. Through 2012, 34 hurricanes had passed within 200 nautical miles of the southern coast of Newfoundland.
The most vivid recent example of this was Hurricane Igor in 2010.
Interacting with a stalled frontal boundary and benefiting from jet-stream level energy, Igor hammered Newfoundland on Sep. 21, 2010, with torrential rain and destructive winds.
The town of St. Lawrence measured 9.37 inches of rain, unprecedented for that location. Severe river flooding washed out many roads and bridges in eastern Newfoundland, isolating some communities for weeks. Wind gusts up to 107 mph downed numerous trees, damaged buildings and lead to widespread power outages.
Igor was the most destructive tropical cyclone in at least 75 years in Newfoundland, with total damage estimated at $200 million.
Interestingly, the deadliest U.S. hurricane on record took a swipe through eastern Canada.
The infamous 1900 Galveston, Texas hurricane may have claimed up to 232 lives in eastern Canada, a large number of those likely in offshore vessels.
Arabian Peninsula
Let's be honest. The only two weather phenomena that immediately come to mind when I mention the Arabian Peninsula are extreme heat and sandstorms, right?Tropical cyclones are not unusual at all in the Arabian Sea, as you can see on the track map on the first page of this article. One as strong as June 2007, however, was beyond anything in memory.
(MORE: Where the Hurricane Season Peaks Twice)
On June 4, 2007, Cyclone Gonu intensified to a Category 4 equivalent tropical cyclone, the strongest ever recorded in the northwest Arabian Sea, then tracked northwest toward the Sultanate of Oman. Its minimum estimated pressure of 920 millibars places it within only two millibars of Hurricane Hugo's peak intensity in 1989.
To set the stage for how unusual this storm was, Weather Underground's Margie Kieper painted an excellent pre-storm picture of eastern Oman, as Gonu approached:
"Imagine you live...in a place where it hardly ever rains, and where a hurricane has never hit, for at least a generation. You don't have any idea what it might mean to experience winds over 100 mph, whipping up sand, and torrential rain against these mountains that can turn the riverbeds into conduits for dangerous flash floods. And you don't have any idea what storm surge is, and can't conceive of wind-driven high waves that could break against the shoreline and leave nothing behind."
While drier, more stable air weakened Gonu prior to landfall, there wasn't enough time to minimize impacts in Oman.
A storm surge of over 16 feet was later documented using high-water marks, swamping and, in many cases, washing out roads. Up to 24 inches of rain in this desert environment turned normally dry riverbeds into torrents of floodwater.
Oman's worst natural disaster claimed at least 49 lives, with damage estimated at $4.2 billion. The story didn't end in Oman, however. Cyclone Gonu then became only the second landfalling cyclone of record in Iran, the first since Jun. 4, 1898. Officially, 28 were killed as Gonu produced almost three inches of rain and a storm tide up to 6.5 feet along the southeast Iranian coast.
Interestingly, almost three years later, Cyclone Phet tracked over the eastern tip of Oman as a Category 1 equivalent tropical cyclone, claiming another 24 lives in the sultanate.
Almost a Spain Hurricane
Track of Hurricane Vince in early-mid October 2005.The destruction and records left by the wayside during the 2005 Atlantic hurricane season may still be fresh in your mind. The most bizarre of the season's 28 storms and 15 hurricanes, however, may have been long forgotten.
The
center of what was then Tropical Depression Vince is seen in the lower
portion of this radar image as it brought rain to southern Portugal and
southwest Spain on Oct. 11, 2005.Succumbing to increasing wind shear, Hurricane Vince weakened almost as quickly as it strengthened, with the center limping ashore near Huelva, Spain on October 11.
While there were no reports of either fatalities or damage, and rainfall was generally less than two inches in most areas, Vince was the first known tropical cyclone to landfall on the Iberian Peninsula.
Ireland
Track of Hurricane Debbie in September 1961, from the Cape Verde Islands to extreme northwest Ireland.Recent examples of western European remnants include Katia in 2011, Bill in 2009 and Lili in 1996.
In September 1961, Hurricane Debbie curled from the Cape Verde Islands off west Africa to the central Atlantic, strengthening to a Category 3 hurricane. One week after its formation, Debbie took a sharp dog-leg right, whisked by strong upper-level winds.
After swinging through The Azores as a hurricane, the meteorological details become a bit controversial.
According to the Atlantic hurricane best track database, Debbie was still a tropical cyclone as its center brushed western Ireland on Sep. 16, 1961 (plotted above). The Irish Meteorological Service (IMS) said "Debbie retained many hurricane characteristics when it arrived off the southwest coast (of Ireland)." However, the final report on Debbie from the National Hurricane Center said Debbie "took on the characteristics of a middle latitude cyclone" (i.e., not a tropical cyclone) after passing near The Azores.
Regardless of this, the impact was severe.
Winds gusted to 113 mph at Malin Head, Ireland, which is tied for the highest wind gust on record in Ireland, according to the IMS. Thousands of trees and power lines were downed, many buildings were damaged and 18 were killed across Ireland and Northern Ireland.
Mediterranean Sea
Infrared satellite image of the Nov. 2011 tropical storm in the Mediterranean Sea off the French Riviera. (EUMETSAT)Imagine your vacation to the French Riviera, Italy, or Greece interrupted by a hurricane. First, some background.
In the meteorological community, there is some debate whether past vigorous low-pressure centers over the Mediterranean Sea were truly tropical cyclones, or a combination of a tropical and more typical mid-latitude low-pressure center, known as a subtropical cyclone.
These Mediterranean lows form as low pressure aloft becomes cut off from the jet stream and percolates convection near its center. If convection persists enough over sufficiently warm water, the originally cold-core upper-low can transform to a warm-core, intensifying cyclone. Given this, they can form not only in late summer or fall, but also in winter and early spring.
One argument for so-called "medicanes" is the appearance of some recent storms via satellite resembling small hurricanes, including an eye.
The most vivid recent example of this was in January 1995. National Hurricane Center Senior Hurricane Specialist, Dr. Jack Beven, chronicled this impressive storm, including satellite imagery.
In early November 2011, another low over the Mediterranean Sea appeared to have transitioned to at least a subtropical storm, if not a tropical storm. NOAA/NESDIS designated this Tropical Storm 01M, also called "Rolf", on Nov. 7. Weather Underground's Dr. Jeff Masters, however, noted water temperatures near the cyclone were quite cold, on the order of 63 degrees Fahrenheit (17C), well below the typical threshold needed to maintain a tropical cyclone (usually around 79 degrees Fahrenheit).
Nevertheless, the storm made landfall in southeast France, producing up to two feet of rain, triggering major flooding in parts of France, Spain, and Italy. Twelve were killed.
In a warming world, could these medicanes become more common?
Dr. Masters' Nov. 2011 blog cited a 2007 study by Gaertner et al., purporting hurricanes could form in the Mediterranean Sea if sea-surface temperatures rose by 3 degrees Celsius by 2100.
That said, Dr. Masters also points out three main barriers to strong medicanes in the future:
- The jet stream still typically dips southward over the Mediterranean Sea quite often, given its northern latitude.
- The key to tropical cyclone formation in other basins is the depth of warm water available, not just warmth at the surface. The Mediterranean Sea is not supplied with deep, warm water like the western Atlantic Ocean is from the Gulf Stream.
- Various island and land masses jutting out (Italy, Sicily, Corsica, Sardinia, Greece) would disrupt the circulation.
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