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Rare Hurricane Pounds Cape Verde Islands

By: Jeff Masters and Bob Henson 4:23 PM GMT on August 31, 2015

For the first time since 1892, a full-fledged hurricane is pounding the Cape Verde islands, as Hurricane Fred heads northwest at 12 mph through the islands in the far eastern North Atlantic. The eye of Fred passed just southwest of Boa Vista Island in the Republic of Cabo Verde (formerly called the Cape Verde Islands) near 8 am EDT Monday, with the northeastern eyewall likely hitting the island. The center of Fred is expected to pass over or very close to the northwestern Cape Verde islands of Sao Nicolou, Santa Luzuia, Sao Vicente, and Sao Antao by Monday night. All three reporting stations in the islands went off-line early Monday morning, so we have no observations to report. Despite their name (which translates to “green cape” in English), the Cape Verde islands have a semi-desert climate, with an average annual rainfall of only around 10 inches. The torrential rains of 4 - 6" predicted from Fred, with isolated totals of up to 10”, are likely to cause unprecedented flood damage on the islands. Fred may well turn out to be the Republic of Cabo Verde's most expensive natural disaster in history.


Figure 1. MODIS image of Hurricane Fred from NASA's Terra satellite taken at approximately 11:15 am EDT Monday August 31, 2015. At the time, Fred had top sustained winds of 85 mph. Image credit: NASA.


Figure 2. MODIS image of Hurricane Fred from NASA's Aqua satellite taken at approximately 8:15 am EDT Monday, August 31, 2015. At the time, Fred had top sustained winds of 80 mph. Image credit: NASA.

Most easterly hurricane formation location ever observed
Fred was able to form and intensify at an unusually easterly location, due to a pocket of anomalously warm waters (1-2°C above average, or about 27-28°C) that surround the Cape Verde islands. Since ocean temperatures are often just marginally warm enough to support tropical cyclones near the islands, it is rare to see a tropical storm or hurricane affect them. When Fred became a hurricane at 2 am EDT Monday at 22.5°W longitude, this was the easternmost formation location for any hurricane in the historical record; the previous record was held by Hurricane Three of 1900, which became a hurricane at 23°W, south of the Cape Verde islands. There have been six other hurricanes in the historical records that existed at a more easterly longitude, but all were recurving storms that formed much farther to the west than Fred. (The easternmost hurricane ever observed was Hurricane Faith of 1966, which maintained hurricane status to a position north of the British Isles, at 2.9°W.)


Figure 3. Tracks of all tropical cyclones in the vicinity of the Cape Verde islands from the NOAA historical database, which extends back to 1851 (although reports were scanty from the far eastern Atlantic until the satellite era began in the 1960s). Only a handful of tropical depressions (blue lines) and tropical storms (green lines) have affected the islands, and no direct hurricane landfalls (yellow lines) have been recorded. The two yellow tracks labeled above are an unnamed 1892 hurricane and 1998’s Hurricane Jeanne. When the National Hurricane Center named Fred at 5:00 am EDT Sunday, it was located at 18.9°W longitude; only three other named storms have existed at a more easterly longitude since hurricane records began in 1851. Ginger of 1967 at 18.1°W; Storm 3 of 1900 at 18.5°W; and Storm 6 of 1988 at 18.5°W. Image credit: NOAA Historical Hurricane Tracks.

A historic hurricane for the Cape Verdes?
The Atlantic's most terrifying and destructive hurricanes typically start as tropical waves that move off the coast of Africa and pass near the Cape Verde islands. This class of storms is referred to as "Cape Verde hurricanes", in reference to their origin. Despite the fact that the Atlantic's most feared type of hurricanes are named after the Cape Verde islands, the islands themselves rarely receive significant impacts from one of their namesake storms. This is because tropical waves coming off the coast of Africa have very little time to organize into tropical storms before arriving at the Cape Verde islands, which lie just 350 miles west of the African coast. There is no reliable record of any bona fide hurricane having made landfall on the Cape Verde islands (see Figure 2). The closest analogue for Fred is an 1892 storm that bisected the islands, moving between the northern cluster (Ilhas do Barlavento, or windward islands) and the southern cluster (Ilhas do Sotavento, or leeward islands). This 1892 storm reportedly intensified to hurricane strength while passing south of the northwestern Cape Verde islands. Another close approach came from 1998’s Hurricane Jeanne, which reached hurricane strength while passing about 100 miles south of the southern islands. Decaying tropical cyclones in the open Atlantic have occasionally circled southeastward to take a swipe at the Cape Verdes as extratropical storms, but none have reached the island at hurricane strength.

According to EM-DAT, the International Disaster Database, there have been only two deadly tropical cyclones in Cape Verde history. Like Jeanne, they both passed south of the Ilhas do Sotavento. The deadliest was Tropical Storm Fran of 1984, which brushed the southernmost islands on September 16 as a tropical storm with 50-mph winds. Fran brought sustained winds of 35 mph and torrential rains to the islands. The rains triggered flash flooding that killed more than two dozen people and caused damages of almost $3 million (1984 dollars.) The other deadly named storm was Tropical Storm Beryl of 1982, which passed about 30 miles south of the southwestern islands on August 29, with 45-mph winds. The storm's heavy rains killed three people on Brava Island, injured 122, and caused $3 million in damage.

The most recent named storm to affect the islands was Hurricane Humberto of 2013, which passed the islands to the south as a tropical storm. Humberto brought wind gusts of up to 35 mph and heavy rain squalls to the islands, triggering flooding that washed out roads and damaged homes. Hurricane Julia of 2010, the easternmost Category 4 hurricane ever recorded in the Atlantic, passed about 50 miles south of Sao Filipe, on the island of Fogo in the southern Cape Verde islands, as a tropical storm with 45 mph winds, bringing wind gusts of 30 mph and some minor flooding.


Figure 4. Track of Tropical Storm Fran of 1984, which brushed the southwestern Cape Verde islands on September 16 as a tropical storm with 50 mph winds. Torrential rains from Fran killed at least 29 people in the Cape Verde islands, making it the deadliest storm in their history.

Hurricane historian Mike Chenoweth, who has spent innumerable hours poring over dusty old ship logs, has published a number of histories of old hurricanes. Here are his comments on the history of hurricanes in the Cape Verde islands:

"There is very little data from land stations in the islands even for storms we know about that pass over or near the islands, particularly before the mid-20th century. The only hurricane in the HURDAT record (1892) is based on a single press account which does not specify any particular island that received the damage (it took a month for the news to get from the islands to Lisbon).

"It is very likely that the storm history for the islands is under-estimated given the paucity of available land and ship data in existing data bases. For example, storm 2 of 1927 has a tropical storm passing between the islands (without a direct island landfall as in 1892) but there are no accounts of any effects the storm may have had on the islands. That such effects probably occurred but remain unrecovered is supported by the report of a hurricane near the Cape Verde islands reported by the "E.R. Sterling" which sailed from Port Adeliade, Australia on 16 April 1927 for London. The ship was damaged in a storm north of the Falkland Islands on 4 July and partially dismasted but continued northward. It then encountered a hurricane near the Cape Verde islands on 4 September and lost her foremast and the Chief Officer was killed. The ship was forced to put into St. Thomas, Virgin Islands on 15 October. So the storm was apparently stronger than indicated in HURDAT and may have been stronger in the Cape Verde islands as well. Source: http://www.dragonsearch.asn.au/nletters/MLSSA_NL_370_October_2009.htm.

"In 1901, a storm was estimated to have passed south of the northern islands of the Cape Verde islands based on press accounts that I provided to the Best Track Change Committee. At the time there were no land reports from the islands in the map series or from press accounts. Today, I located a press item from the local Cape Verde press that indicates that on 29 August on Santo Antao two vessels were lost, much of the coffee and sugar cane was blown down and washed away and that mighty winds swept houses away and killed livestock and people. Most of the other islands reported at least torrential rains and flood damage. Source: "O Ultramarino" (Cidade de Praia), 17 de Outburo de 1901, nº 64, ano3, p. 2.

"In 1880, the Bremen brig "Asante" encountered a tropical storm in 15.5N 20.2W on 17 August, lowest pressure 752.3mm (1003mb) maximum winds encountered force 11 from the south. (Deutsche Seewarte, Segelhandbuch für den Atlantischen Ozean, 1899, p.187). A brig drove off from her anchorage on the night of 17-18 August on the Island of Sal in the northeast Cape Verde islands during a "severe hurricane" and was lost on the island and the crew saved (Lloyd's List, 8 September 1880).

"The most severe storm on record in the Cape Verde Republic's history pre-dates the official North Atlantic record. This was a hurricane and was felt on 2 September 1850. The first account of it was in the Boston Atlas of 3 December 1850 which reported a hurricane had caused great destruction of property; on the island of St. Antonio alone more than 600 houses were destroyed by the wind and rain combined; several American vessels were wrecked or damaged at the islands of Sal and Boa Vista. The London Times of 1 February 1851 had additional information. It stated that the storm on the island of San Nicolas was a "fearful hurricane" it began early in the morning before daylight and although it continued until the next morning, all of the damage was done in the first 3 or 4 hours, the wind blowing with such terrific violence during that short period that nearly all the crops and 600 houses were completely destroyed...the whole of the sattara root had been torn up and destroyed by the hurricane.

"In short, the official records are incomplete and although hurricane impacts are rare in the Cape Verde Islands they are not quite the unicorns we have thought to date."


Figure 3. The view from inside the eye of Hurricane Ignacio on Sunday, August 30, 2015, from an Air Force hurricane hunter aircraft. At the time, Ignacio was a Category 4 storm with 140 mph winds. Image credit: Air Force Reserve 403rd Wing. There is also an impressive video from inside the eye on their Twitter page.

Ignacio no longer a threat to Hawaii; Pacific storm show goes on
In the Central Pacific, all watches and warnings have been dropped for Hawaii due to Hurricane Ignacio, which has weakened to Category 2 strength and is expected to skirt the islands over 300 miles to their northeast. Ignacio, will, however, bring dangerous high surf to the islands, and a High Surf Warning for waves of 12 - 20 feet along east shores of the Big Island has been posted. Impressive Category 4 Hurricane Jimena, and Category 4 Hurricane Kilo continue to put on a show over the open waters of the Eastern Pacific, but neither of these storms are a threat to land. All three hurricanes reached Category 4 strength on Saturday and remained there on Sunday morning, the first time since the satellite era began in the 1960s that three simultaneous Category 4 hurricanes had existed in the waters of the Eastern Pacific, east of the Date Line.

Links
Storm surge expert Hal Needham has a Monday morning post on the storm surge potential for Fred in the Cape Verde islands.

Live webcam from Sal Island in Cabo Verde.

Live blog on Fred (in Portugese) from the islands.

We’ll be back with another update on Tuesday.

Jeff Masters and Bob Henson

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Quoting 497. sar2401:

That would be Cat 3 or above hurricanes for the CONUS, or any hurricane for Florida. Last hurricane to hit Florida was Wilma in October, 2005.


Yeah I know that, I was gunna say that too because there were no Florida hurricane strikes in 2006.

I just forgot to write it haha.
Quoting 481. tornadodude:




Hey, TD. That is what is known as a perma-Blob.
Quoting 493. rxse7en:


Thanks. Don't remember it being there yesterday. WU probably just keeping it warm in case 90L is back later. :)
Ya' never know. With Fred headed off to a watery grave and not much else from the African wave train, the persistent trough off Florida may be the only thing to get the heavy breathing going here over the next week or so. :-)
Quoting 500. Grothar:



That is known as an elasticated blob; stretched out until it resembles a pastel shade of light orange.

If you want some action, look at the Atlantic coast this week.


Excellent designation.

Presslord has the Atlantic duty, esp the mythical "Carolina's".
JeffMasters has created a new entry.
Looks like Tampas shields still work...
Quoting 504. Patrap:



Excellent designation.

Presslord has the Atlantic duty, esp the mythical "Carolina's".
Checking in from the NW FL Coastline.. Not so humid this morning.. slight NE breeze with calm waters.. dolphins playing, birds flying, crabs are crabby, all is well in Blue Mountain Beach. Blessings to the WU crew on this fine Tuesday.
Quoting 268. stormpetrol:



very sad, it was plain to see the storm was headed in their direction with heavy convection south of the center at that time !


-Its So Good to be Alive and Blessed!!! (Post Erika)...
Indeed it is extremely tragic to have witnessed what ultimately happened in Dominica the Nature isle since the passage of Tropical Storm Erika. Horrifically -the catastrophic onslaught from Erika more than validated 1000 x 1,000,000 times what I was constantly voicing just prior to the impact from Erika -and for Danny likewise as a matter of fact...That warnings or at the very least watches were required for our island and its populace. It was a form of intuition and premonition, but thank God was quite prophetic, accurate and critical in nature to all parties concerned within the island. If and Only if it was heeded by the authorities that be. I will continually lament this- as utterly unacceptable incompetence by the Meteorological offices/ services both regionally and locally. What an incomprehensibly tragic, and perplexingly fateful day the 27th August 2015 turned out to be for our island Dominica. one that we will never forget. Altogether, my unofficial totals for the storm amounted to about 18.5 inches which is very consistent with the resultant flood damages and destruction which we witnessed in an unprecedented way throughout that absolutely horrendous and terrifying day.
I myself along with others have posted other crucial updates and reports on the overall situation on the Dominica page at Stormcarib.com which the online community here an feel free to review and peruse.

We are surviving by God's grace, however help is quickly arriving & we are continually encouraged and supported by the pledges of countless foreign friendly governments and agencies. Your sincere and express concerns and solidarity with Dominica and its people at this time has been definitely invaluable. Please continue to do all You can to further the Recovery efforts in Dominica- Nature Island of the Caribbean. N.B. (Telecoms and Internet service has been much slower to return to the farther reaches of the country such as the North east coast where I'm located and it remains sporadic...besides & perhaps much more significantly the sheer weight and magnitude of the disaster has had a severe material, mental, economic, social and critical unimaginable human impact that at times feels bewildering and certainly depressing...I can underscore that its a lot more serious than what meets the eye via -images, videos or tweets) We remain strong & Hopeful Nevertheless; This TOO shall Pass...Blessings to All!
Quoting 392. Jedkins01:

With the devastation that Erika caused to Dominica, I can't help but wonder how often such flash floods happen the island, and how common heavy rain events are there.

I didn't realize the leeward islands further south had such a rainy climate with such lush rain forests. The capital city Roseau on Dominica lies on the driest region of the island, and still has a yearly average precip of 101 inches and 3 months average more than 11 inches per month. the even rainier leeward side averages around 200 inches per year, and some of the higher terrain areas receive up to 350 inches per year.

Link

With that said, either these type of flash flood events like Erika are really common or usually this rainy island gets it's rainfall in frequent heavy showers of short duration. Even still any climate that rainy in a tropical area must get 10 inches in a day more often than most areas.

Which then makes me wonder. Having had read about the island, most of the population is on the "drier" although still a very wet climate, while the higher terrain is little to no population. Nothing but lush rain forests for the most part. So more than likely the rain reports from Dominica, while very impressive, only begin to tell the story of possibly just how much rain actually fell from Erika. It's likely the high terrain areas had much more rain than what was even recorded.

You can only imagine if low land populated areas had more than 10 inches in less than a day, then God only knows just how extreme the rainfall rates up in the mountains were where the fast tropical flow is forced to rise over the peaks. All that torrential rain upland accelerated downhill into populated areas causing the death and destruction.



-Its So Good to be Alive and Blessed!!! (Post Erika)...
Indeed it is extremely tragic to have witnessed what ultimately happened in Dominica the Nature isle since the passage of Tropical Storm Erika. Horrifically -the catastrophic onslaught from Erika more than validated 1000 x 1,000,000 times what I was constantly voicing just prior to the impact from Erika -and for Danny likewise as a matter of fact...That warnings or at the very least watches were required for our island and its populace. It was a form of intuition and premonition, but thank God was quite prophetic, accurate and critical in nature to all parties concerned within the island. If and Only if it was heeded by the authorities that be. I will continually lament this- as utterly unacceptable incompetence by the Meteorological offices/ services both regionally and locally. What an incomprehensibly tragic, and perplexingly fateful day the 27th August 2015 turned out to be for our island Dominica. one that we will never forget. Altogether, my unofficial totals for the storm amounted to about 18.5 inches which is very consistent with the resultant flood damages and destruction which we witnessed in an unprecedented way throughout that absolutely horrendous and terrifying day. Both Windward (East coast- typically more rainy and the Leeward side of the island received unprecedented rainfall totals with more occurring in the East and Mountainous interior of the island.)
I myself along with others have posted other crucial updates and reports on the overall situation on the Dominica page at Stormcarib.com which the online community here an feel free to review and peruse.

We are surviving by God's grace, however help is quickly arriving & we are continually encouraged and supported by the pledges of countless foreign friendly governments and agencies. Your sincere and express concerns and solidarity with Dominica and its people at this time has been definitely invaluable. Please continue to do all You can to further the Recovery efforts in Dominica- Nature Island of the Caribbean. N.B. (Telecoms and Internet service has been much slower to return to the farther reaches of the country such as the North east coast where I'm located and it remains sporadic...besides & perhaps much more significantly the sheer weight and magnitude of the disaster has had a severe material, mental, economic, social and critical unimaginable human impact that at times feels bewildering and certainly depressing...I can underscore that its a lot more serious than what meets the eye via -images, videos or tweets) We remain strong & Hopeful Nevertheless, this too shall Pass... Blessings to All!
Better hope climate change doesn't cause the leeward islands to snow... They would be the snowiest place on Earth when you do the rain to snow conversion. Even if you use very conservative conversion estimates.