Hurricane Danielle (2010)
Encyclopedia
Hurricane Danielle was the first of four Category 4 hurricanes
during the 2010 Atlantic hurricane season
. The sixth tropical depression, fourth named storm, second hurricane, and first major hurricane of the season, Danielle developed as a typical Cape Verde-type hurricane
from a tropical wave
on August 21. Quickly intensifying, the new tropical depression became a tropical storm eighteen hours after formation on August 22, and it reached category 2 on August 24. Also on August 24, Hurricane Danielle weakened back to a category 1 hurricane, but it returned to category 2 strength on August 25. Further intensification occurred and Danielle became a Category 4 hurricane with peak winds of 135 miles per hour (217.3 km/h) on August 27. It then weakened, and finally dissipated on August 30. The hurricane was the first in a rapid succession of eleven named storms, which ended in late September.
that had formed two days earlier off Africa
's western coast interacted with a large tropical disturbance in the Intertropical Convergence Zone
. This disorganized disturbance covered an area from the southwest of Senegal
to the south of the Cape Verde Islands while slowly moving west. The National Hurricane Center
(NHC) began monitoring the system, initially giving this area of disturbed weather a 20% chance of development. As it moved through favorable conditions, the system became more organized and began circulating at a low level. On August 20, 8:00 AM EDT, the National Hurricane Center gave the disturbance a 40% chance of becoming a tropical cyclone during the following 48 hours. The NHC stated that a broad area of low pressure had formed, and conditions were favorable for further development. The system continued to organize, and the chance was raised to the "high" category on August 21 at 2:00 PM EDT, indicating at least 60% probability of development into a tropical cyclone within the following 48 hours. The tropical disturbance became banded and the convection became even more organized.
Late that afternoon, the system was designated as Tropical Depression Six. As the depression tracked slowly westward, it quickly intensified. The following day, it was upgraded to Tropical Storm Danielle, the fourth tropical storm of the season. Slow intensification ensued as Danielle headed generally westward and eventually became the second hurricane of the season on August 23, with hurricane-force winds extending outward for a 10 miles (16.1 km) radius. Hurricane Danielle reached an initial peak intensity on August 24 at category 2 with a maximum wind speed of 100 mile per hour and hurricane-force winds extending out for 30 miles (48.3 km), However, later that day, Danielle began to rapidly weaken as it encountered an area of high wind shear
and dry air. Danielle weakened to a category 1 hurricane with 75 mile per hour winds late on August 24. Danielle quickly re-intensified early on the night of August 24-25, and it had hurricane-force winds in a 30 miles (48.3 km) radius from the center. Further intensification was gradual, and Danielle again reached category 2 strength late on August 25, and an eye
was present on satellite images. It had hurricane-force winds extending outwards 40 miles (64.4 km) from the center. After a few days of gradual strengthening, Danielle began to rapidly intensify
on August 27, and became the first major hurricane of the season with winds of 120 mile per hour. Hurricane-force winds extended out for 50 miles (80.5 km), and tropical storm-force winds extended out for 205 miles (329.9 km). Continuing the rapid intensification, Hurricane Danielle briefly became a category 4 hurricane on August 27, when it was situated 545 miles (877.1 km) southeast of Bermuda
, attaining its peak intensity with winds of 135 mile per hour and a minimum barometric pressure of 942 mbar (hPa; 27.82 inHg). The hurricane-force winds were in a radius of 60 miles (96.6 km), and the tropical storm-force winds extended out for 205 miles (329.9 km) from the center.
However, on August 28, Danielle encountered a large middle-level to upper-level weather trough moving off the coast of the eastern United States into the Atlantic Ocean. This pushed Danielle north-northeast. The inner of Danielle's two eye walls eroded as the hurricane weakened. During this time, Hurricane Danielle's outflow exposed the core of the more southerly Hurricane Earl
. However, Hurricane Earl (then a tropical storm) retained strong circulation, and the center eventually moved back into the convection
flow. The outflow from Danielle kept Earl a tropical storm before Danielle accelerated north and northeastward. As Danielle moved into a region with cooler sea surface temperature
s and higher wind shear, it began to weaken at a steady pace and slowly began its extratropical transition. Danielle weakened to a category 1 hurricane on August 29, and became a tropical storm on the afternoon of August 30. Accelerating northeastward, Danielle completed the extratropical transition later that day. During the next few days, the extratropical remnants of Hurricane Danielle moved across the northern Atlantic Ocean
, and were forecast to move into the area of Greenland
and Iceland
over the next five days. However, on September 3, Danielle's remnants dissipated after 72 hours in the cold waters of the northern Atlantic Ocean.
Hurricane Danielle and Hurricane Earl caused strong ocean swells and rip current
s on the coasts of New Jersey, Delaware, and Maryland. which swept people out to sea. In Florida, around 250 people from Ocean City
were swept out to sea, and at least one person was drowned by the riptides. At least 70 more people had to be rescued off the remaining coast of eastern central Florida. On August 31, despite being more than 475 miles (764.4 km) from Newfoundland, Tropical Storm Danielle still caused 10 feet (3 m) waves on its shores.
Researchers exploring the sunken remnants of the RMS Titanic were forced to leave the area when Danielle approached on August 29.
Saffir-Simpson Hurricane Scale
The Saffir–Simpson Hurricane Scale , or the Saffir–Simpson Hurricane Wind Scale , classifies hurricanes — Western Hemisphere tropical cyclones that exceed the intensities of tropical depressions and tropical storms — into five categories distinguished by the intensities of their sustained winds...
during the 2010 Atlantic hurricane season
2010 Atlantic hurricane season
The 2010 Atlantic hurricane season was the third most active Atlantic hurricane season on record, tying with the 1887 Atlantic hurricane season, 1995 Atlantic hurricane season and the 2011 Atlantic hurricane season. It had the most number of named storms since the 2005 season and also ties with the...
. The sixth tropical depression, fourth named storm, second hurricane, and first major hurricane of the season, Danielle developed as a typical Cape Verde-type hurricane
Cape Verde-type hurricane
A Cape Verde-type hurricane is an Atlantic hurricane that develops near the Cape Verde islands, off the west coast of Africa. The average hurricane season has about two Cape Verde-type hurricanes, which are usually the largest and most intense storms of the season because they often have plenty of...
from a tropical wave
Tropical wave
Tropical waves, easterly waves, or tropical easterly waves, also known as African easterly waves in the Atlantic region, are a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which move from east to west across the tropics causing areas of...
on August 21. Quickly intensifying, the new tropical depression became a tropical storm eighteen hours after formation on August 22, and it reached category 2 on August 24. Also on August 24, Hurricane Danielle weakened back to a category 1 hurricane, but it returned to category 2 strength on August 25. Further intensification occurred and Danielle became a Category 4 hurricane with peak winds of 135 miles per hour (217.3 km/h) on August 27. It then weakened, and finally dissipated on August 30. The hurricane was the first in a rapid succession of eleven named storms, which ended in late September.
Meteorological history
On August 20, a tropical waveTropical wave
Tropical waves, easterly waves, or tropical easterly waves, also known as African easterly waves in the Atlantic region, are a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which move from east to west across the tropics causing areas of...
that had formed two days earlier off Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
's western coast interacted with a large tropical disturbance in the Intertropical Convergence Zone
Intertropical Convergence Zone
The Intertropical Convergence Zone , known by sailors as The Doldrums, is the area encircling the earth near the equator where winds originating in the northern and southern hemispheres come together....
. This disorganized disturbance covered an area from the southwest of Senegal
Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...
to the south of the Cape Verde Islands while slowly moving west. 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) began monitoring the system, initially giving this area of disturbed weather a 20% chance of development. As it moved through favorable conditions, the system became more organized and began circulating at a low level. On August 20, 8:00 AM EDT, the National Hurricane Center gave the disturbance a 40% chance of becoming a tropical cyclone during the following 48 hours. The NHC stated that a broad area of low pressure had formed, and conditions were favorable for further development. The system continued to organize, and the chance was raised to the "high" category on August 21 at 2:00 PM EDT, indicating at least 60% probability of development into a tropical cyclone within the following 48 hours. The tropical disturbance became banded and the convection became even more organized.
Late that afternoon, the system was designated as Tropical Depression Six. As the depression tracked slowly westward, it quickly intensified. The following day, it was upgraded to Tropical Storm Danielle, the fourth tropical storm of the season. Slow intensification ensued as Danielle headed generally westward and eventually became the second hurricane of the season on August 23, with hurricane-force winds extending outward for a 10 miles (16.1 km) radius. Hurricane Danielle reached an initial peak intensity on August 24 at category 2 with a maximum wind speed of 100 mile per hour and hurricane-force winds extending out for 30 miles (48.3 km), However, later that day, Danielle began to rapidly weaken as it encountered an area of high 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...
and dry air. Danielle weakened to a category 1 hurricane with 75 mile per hour winds late on August 24. Danielle quickly re-intensified early on the night of August 24-25, and it had hurricane-force winds in a 30 miles (48.3 km) radius from the center. Further intensification was gradual, and Danielle again reached category 2 strength late on August 25, and an eye
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...
was present on satellite images. It had hurricane-force winds extending outwards 40 miles (64.4 km) from the center. After a few days of gradual strengthening, Danielle began to rapidly intensify
Rapid deepening
Rapid deepening, also known as rapid intensification, is a meteorological condition that occurs when the minimum sea-level atmospheric pressure of a tropical cyclone decreases drastically in a short period of time. The National Weather Service describes rapid deepening as a decrease of...
on August 27, and became the first major hurricane of the season with winds of 120 mile per hour. Hurricane-force winds extended out for 50 miles (80.5 km), and tropical storm-force winds extended out for 205 miles (329.9 km). Continuing the rapid intensification, Hurricane Danielle briefly became a category 4 hurricane on August 27, when it was situated 545 miles (877.1 km) southeast of 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...
, attaining its peak intensity with winds of 135 mile per hour and a minimum barometric pressure of 942 mbar (hPa; 27.82 inHg). The hurricane-force winds were in a radius of 60 miles (96.6 km), and the tropical storm-force winds extended out for 205 miles (329.9 km) from the center.
However, on August 28, Danielle encountered a large middle-level to upper-level weather trough moving off the coast of the eastern United States into the Atlantic Ocean. This pushed Danielle north-northeast. The inner of Danielle's two eye walls eroded as the hurricane weakened. During this time, Hurricane Danielle's outflow exposed the core of the more southerly Hurricane Earl
Hurricane Earl (2010)
Hurricane Earl was a long-lived, powerful tropical cyclone which became the first major hurricane to threaten New England since Hurricane Bob in 1991. The fifth named storm of the 2010 season, Earl developed out of a tropical wave roughly west of the Cape Verde Islands on August 25...
. However, Hurricane Earl (then a tropical storm) retained strong circulation, and the center eventually moved back into the convection
Convection
Convection is the movement of molecules within fluids and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids....
flow. The outflow from Danielle kept Earl a tropical storm before Danielle accelerated north and northeastward. As Danielle moved into a region with cooler sea surface temperature
Sea surface temperature
Sea surface temperature is the water temperature close to the oceans surface. The exact meaning of surface varies according to the measurement method used, but it is between and below the sea surface. Air masses in the Earth's atmosphere are highly modified by sea surface temperatures within a...
s and higher wind shear, it began to weaken at a steady pace and slowly began its extratropical transition. Danielle weakened to a category 1 hurricane on August 29, and became a tropical storm on the afternoon of August 30. Accelerating northeastward, Danielle completed the extratropical transition later that day. During the next few days, the extratropical remnants of Hurricane Danielle moved across the northern 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...
, and were forecast to move into the area of Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
and Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
over the next five days. However, on September 3, Danielle's remnants dissipated after 72 hours in the cold waters of the northern Atlantic Ocean.
Preparations and impact
On August 27, a tropical storm watch was issued on Bermuda before being canceled during the afternoon of August 28 because Danielle turned sharply east. However, it still triggered an advisory concerning high surf and large waves on Bermuda.Hurricane Danielle and Hurricane Earl caused strong ocean swells and rip current
Rip current
A rip current, commonly referred to by the misnomer rip tide, is a strong channel of water flowing seaward from near the shore, typically through the surf line. Typical flow is at 0.5 metres per second , and can be as fast as 2.5 metres per second...
s on the coasts of New Jersey, Delaware, and Maryland. which swept people out to sea. In Florida, around 250 people from Ocean City
Ocean City, Florida
Ocean City is a census-designated place in Okaloosa County, Florida, United States. The population was 5,594 at the 2000 census. It is part of the Fort Walton Beach–Crestview–Destin Metropolitan Statistical Area.-Geography:...
were swept out to sea, and at least one person was drowned by the riptides. At least 70 more people had to be rescued off the remaining coast of eastern central Florida. On August 31, despite being more than 475 miles (764.4 km) from Newfoundland, Tropical Storm Danielle still caused 10 feet (3 m) waves on its shores.
Researchers exploring the sunken remnants of the RMS Titanic were forced to leave the area when Danielle approached on August 29.
See also
- Timeline of the 2010 Atlantic hurricane seasonTimeline of the 2010 Atlantic hurricane seasonThe 2010 Atlantic hurricane season was a hyperactive year in which nineteen tropical storms formed, the most since 2005. Although Hurricane Alex formed on June 25, 2010, the season officially began on June 1 and ended on November 30...
- 2010 Atlantic hurricane season2010 Atlantic hurricane seasonThe 2010 Atlantic hurricane season was the third most active Atlantic hurricane season on record, tying with the 1887 Atlantic hurricane season, 1995 Atlantic hurricane season and the 2011 Atlantic hurricane season. It had the most number of named storms since the 2005 season and also ties with the...
- Other storms of the same name