Hurricane Humberto (2001)
Encyclopedia
Hurricane Humberto was a moderately powerful hurricane that briefly affected Bermuda
in September 2001. It was the eighth named storm of the season, as well as the fourth hurricane. It formed on September 21 between Puerto Rico
and Bermuda, partially related to previous Hurricane Gabrielle
. Humberto passed about 140 miles (225 km) west of Bermuda, which spared the island with its strongest winds. After weakening and believed to be on the verge of dissipating, Humberto unexpectedly restrengthened to the southeast of Atlantic Canada
. The intensification was short-lived and the storm dissipated on September 27. There were a series of significant observational flights into the hurricane that produced a wealth of data on the structure of hurricanes.
that extended southwestward from Hurricane Gabrielle
, which had previously moved across Florida
into the western Atlantic Ocean
. The trough interacted with an upper-level low
, resulting in an increase of convection, or thunderstorms, in the region. A surface low developed on September 19, and it gradually organized as it moved westward. After deep convection developed over the center, it is estimated the system reached tropical depression strength (39 miles per hour (62.8 km/h)) on September 21, about halfway between Puerto Rico
and Bermuda
. The National Hurricane Center
(NHC) first published an advisory on the storm at 11 AM EDT
, identifying it as Tropical Depression Ten. Upon its formation, the depression moved northwestward toward a break in the mid-level ridge
. On satellite imagery, the depression looked well-organized, with banding features, outflow, and convection, although Hurricane Hunters
had difficulty locating a closed center of circulation. The unfavorable conditions were from the upper-level low to its southwest, which was producing wind shear
over the storm; nevertheless, the NHC anticipated strengthening.
On September 22, the surface circulation rapidly became better organized, and based on confirmation from the Hurricane Hunters, the NHC upgraded the depression to Tropical Storm Humberto. Throughout its life, the storm was smaller than average, and as it moved around the subtropical ridge, it gradually intensified. Tropical Storm Humberto developed an eye feature
on September 23. Shortly thereafter, the storm reached hurricane status about 175 miles (285 km) west-southwest of Bermuda. After passing about 140 miles (225 km) west of Bermuda, Hurricane Humberto turned more to the northeast, and reached Category 2 status on the Saffir-Simpson scale. Subsequently, strong upper-level westerlies
began affecting the storm, which caused a marked decrease in intensity; by September 25, the winds decreased to 75 mph (120 km/h), or minimal hurricane status. At that time, the NHC expected Humberto to continue weakening due to the shear, as well as steadily decreasing water temperatures.
Unexpectedly, the weakening trend stopped, as the steering winds came from the same direction behind the hurricane. It slowed down slightly, and on September 26 the eye of the hurricane became much more distinct. Humberto quickly re-intensified and reached peak winds of 105 mph (170 km/h), while located about 200 miles (320 km) south-southeast of Sable Island
, off the coast of Nova Scotia
. Just as quickly it strengthened, the hurricane began weakening again. The eye became distorted as the convection became asymmetrical, due to the cooler waters and stronger westerlies. Initially, the NHC forecast Humberto to become extratropical. On September 27, it turned more eastward and later to the east-southeast, and Humberto weakening to tropical storm status about 400 miles (645 km) southeast of Newfoundland. The cloud pattern became increasingly elongated and removed from the center, and late on the 27th, the circulation of Humberto degenerated into an open trough in the far northern Atlantic Ocean. The remnants were expected to be absorbed quickly by a larger extratropical storm to its north.
There were three major aircraft flights into the hurricane over a three day period which, according to NASA
, "were the most comprehensive measurements of the structure of the hurricane ever recorded." The flights were designed to obtain data for better hurricane forecasting.
, the National Hurricane Center advised the residents "should monitor the progress of Humberto until it is safely past." On September 23 when the hurricane passed the island, the hurricane force winds extended 30 miles (50 km) from the center, while tropical storm force winds only extended 105 miles (170 km) from the center. As a result, Bermuda only experienced peak sustained winds of 27 mph (44 km/h), with gusts to 43 mph (69 km/h). During its passage, the island also recorded 1.69 inches (4.3 cm) of rainfall.
Only two ships recorded tropical storm force winds, both of which were away from the center. Some higher surf was recorded along the New Jersey coastline. In September 2001, two men sought to break the record for sailing the quickest time from New York
to Melbourne
, Australia
; Humberto disrupted their early path slightly, but they ultimately broke the record by 28 hours. Later in its path, there were several marine warnings issued for offshore Newfoundland, although no severe weather affected coastal Atlantic Canada
. Overall, there were no reports of casualties or damage from the hurricane.
Bermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
in September 2001. It was the eighth named storm of the season, as well as the fourth hurricane. It formed on September 21 between Puerto Rico
Puerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
and Bermuda, partially related to previous Hurricane Gabrielle
Hurricane Gabrielle (2001)
Hurricane Gabrielle was a moderate category 1 hurricane which made landfall near Venice, Florida as a strong tropical storm. The eighth tropical cyclone, seventh named storm, and third hurricane of the 2001 Atlantic hurricane season, Gabrielle developed from a non-tropical low-to mid-level trough...
. Humberto passed about 140 miles (225 km) west of Bermuda, which spared the island with its strongest winds. After weakening and believed to be on the verge of dissipating, Humberto unexpectedly restrengthened to the southeast of Atlantic Canada
Atlantic Canada
Atlantic Canada is the region of Canada comprising the four provinces located on the Atlantic coast, excluding Quebec: the three Maritime provinces – New Brunswick, Prince Edward Island, and Nova Scotia – and Newfoundland and Labrador...
. The intensification was short-lived and the storm dissipated on September 27. There were a series of significant observational flights into the hurricane that produced a wealth of data on the structure of hurricanes.
Meteorological history
Hurricane Humberto originated from a troughTrough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...
that extended southwestward from Hurricane Gabrielle
Hurricane Gabrielle (2001)
Hurricane Gabrielle was a moderate category 1 hurricane which made landfall near Venice, Florida as a strong tropical storm. The eighth tropical cyclone, seventh named storm, and third hurricane of the 2001 Atlantic hurricane season, Gabrielle developed from a non-tropical low-to mid-level trough...
, which had previously moved across Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
into the western Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
. The trough interacted with an upper-level low
Low pressure area
A low-pressure area, or "low", is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence which occur in upper levels of the troposphere. The formation process of a low-pressure area is known as...
, resulting in an increase of convection, or thunderstorms, in the region. A surface low developed on September 19, and it gradually organized as it moved westward. After deep convection developed over the center, it is estimated the system reached tropical depression strength (39 miles per hour (62.8 km/h)) on September 21, about halfway between Puerto Rico
Puerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
and Bermuda
Bermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
. The National Hurricane Center
National Hurricane Center
The National Hurricane Center , located at Florida International University in Miami, Florida, is the division of the National Weather Service responsible for tracking and predicting weather systems within the tropics between the Prime Meridian and the 140th meridian west poleward to the 30th...
(NHC) first published an advisory on the storm at 11 AM EDT
Eastern Time Zone
The Eastern Time Zone of the United States and Canada is a time zone that falls mostly along the east coast of North America. Its UTC time offset is −5 hrs during standard time and −4 hrs during daylight saving time...
, identifying it as Tropical Depression Ten. Upon its formation, the depression moved northwestward toward a break in the mid-level ridge
Ridge (meteorology)
A ridge is an elongated region of relatively high atmospheric pressure, the opposite of a trough....
. On satellite imagery, the depression looked well-organized, with banding features, outflow, and convection, although Hurricane Hunters
Hurricane Hunters
The Hurricane Hunters are aircraft that fly into tropical cyclones in the North Atlantic Ocean and Northeastern Pacific Ocean for the specific purpose of directly measuring weather data in and around those storms. In the United States, the Air Force, Navy, and NOAA units have all participated in...
had difficulty locating a closed center of circulation. The unfavorable conditions were from the upper-level low to its southwest, which was producing wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...
over the storm; nevertheless, the NHC anticipated strengthening.
On September 22, the surface circulation rapidly became better organized, and based on confirmation from the Hurricane Hunters, the NHC upgraded the depression to Tropical Storm Humberto. Throughout its life, the storm was smaller than average, and as it moved around the subtropical ridge, it gradually intensified. Tropical Storm Humberto developed an eye feature
Eye (cyclone)
The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the second most severe weather of a cyclone...
on September 23. Shortly thereafter, the storm reached hurricane status about 175 miles (285 km) west-southwest of Bermuda. After passing about 140 miles (225 km) west of Bermuda, Hurricane Humberto turned more to the northeast, and reached Category 2 status on the Saffir-Simpson scale. Subsequently, strong upper-level westerlies
Westerlies
The Westerlies, anti-trades, or Prevailing Westerlies, are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles. These prevailing winds blow from the west to the east, and steer extratropical...
began affecting the storm, which caused a marked decrease in intensity; by September 25, the winds decreased to 75 mph (120 km/h), or minimal hurricane status. At that time, the NHC expected Humberto to continue weakening due to the shear, as well as steadily decreasing water temperatures.
Unexpectedly, the weakening trend stopped, as the steering winds came from the same direction behind the hurricane. It slowed down slightly, and on September 26 the eye of the hurricane became much more distinct. Humberto quickly re-intensified and reached peak winds of 105 mph (170 km/h), while located about 200 miles (320 km) south-southeast of Sable Island
Sable Island
Sable Island is a small Canadian island situated 300 km southeast of mainland Nova Scotia in the Atlantic Ocean. The island is a year-round home to approximately five people...
, off the coast of Nova Scotia
Nova Scotia
Nova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
. Just as quickly it strengthened, the hurricane began weakening again. The eye became distorted as the convection became asymmetrical, due to the cooler waters and stronger westerlies. Initially, the NHC forecast Humberto to become extratropical. On September 27, it turned more eastward and later to the east-southeast, and Humberto weakening to tropical storm status about 400 miles (645 km) southeast of Newfoundland. The cloud pattern became increasingly elongated and removed from the center, and late on the 27th, the circulation of Humberto degenerated into an open trough in the far northern Atlantic Ocean. The remnants were expected to be absorbed quickly by a larger extratropical storm to its north.
There were three major aircraft flights into the hurricane over a three day period which, according to NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
, "were the most comprehensive measurements of the structure of the hurricane ever recorded." The flights were designed to obtain data for better hurricane forecasting.
Impact and naming
Prior to its passage by BermudaBermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
, the National Hurricane Center advised the residents "should monitor the progress of Humberto until it is safely past." On September 23 when the hurricane passed the island, the hurricane force winds extended 30 miles (50 km) from the center, while tropical storm force winds only extended 105 miles (170 km) from the center. As a result, Bermuda only experienced peak sustained winds of 27 mph (44 km/h), with gusts to 43 mph (69 km/h). During its passage, the island also recorded 1.69 inches (4.3 cm) of rainfall.
Only two ships recorded tropical storm force winds, both of which were away from the center. Some higher surf was recorded along the New Jersey coastline. In September 2001, two men sought to break the record for sailing the quickest time from New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
to Melbourne
Melbourne
Melbourne is the capital and most populous city in the state of Victoria, and the second most populous city in Australia. The Melbourne City Centre is the hub of the greater metropolitan area and the Census statistical division—of which "Melbourne" is the common name. As of June 2009, the greater...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
; Humberto disrupted their early path slightly, but they ultimately broke the record by 28 hours. Later in its path, there were several marine warnings issued for offshore Newfoundland, although no severe weather affected coastal Atlantic Canada
Atlantic Canada
Atlantic Canada is the region of Canada comprising the four provinces located on the Atlantic coast, excluding Quebec: the three Maritime provinces – New Brunswick, Prince Edward Island, and Nova Scotia – and Newfoundland and Labrador...
. Overall, there were no reports of casualties or damage from the hurricane.