Hurricane Danny (1997)
From Wikipedia, the free encyclopedia
| Category 1 hurricane (SSHS) | ||
|---|---|---|
 Hurricane Danny at peak intensity |
||
| Formed | July 16, 1997 | |
| Dissipated | July 27, 1997 | |
| Highest winds |
|
|
| Lowest pressure | 984 mbar (hPa; 29.07 inHg) | |
| Fatalities | 4 direct, 6 indirect | |
| Damage | $100 million (1997 USD) $125.69 million (2006 USD) |
|
| Areas affected |
Louisiana, Mississippi, Alabama, Florida, Georgia, Virginia, Massachusetts | |
| Part of the 1997 Atlantic hurricane season |
||
Hurricane Danny was the only hurricane to make landfall in the United States during the 1997 Atlantic hurricane season. It was the second hurricane and fourth named storm of the season. Like the previous four tropical or subtropical cyclones of the season, Danny had a non-tropical origin. The disturbance ended a high frequency beginning of the season, with the next tropical cyclone over a month later. The system became the earliest 5th tropical or subtropical storm of a season when it reached tropical storm strength on July 17. During the 2005 Atlantic hurricane season, Tropical Storm Emily attained tropical storm status on July 12, therefore breaking the record. Another unusual fact of Danny was its extended northeast track through the Gulf of Mexico, a rare occurrence in the middle of July, and was caused due to two high pressure systems.
Danny is noted for the extreme rainfall, tornadoes, and damage it produced on its path, causing four direct fatalities and $100 million (1997 USD, $125.69 million 2006 USD) in damage. $5 million (1997 USD, $6.28 million 2006 USD) in damage resulted in Louisiana. $63 million (1997 USD, $79.18 million 2006 USD) in property and crop damage resulted in Alabama. Elsewhere it caused less then $32 million (1997 USD, $40.22 million 2006 USD) in property and crop damage. The storm dropped a record rainfall for Alabama, 36.71 inches (932 mm) on Dauphin Island. Flooding, power outages, and erosion occurred in many areas of the Gulf Coast, and rescues from flooded roads had to be performed. Most of the damage on the East Coast was from various tornadoes that caused damage on the ground. The storm moved across the southeastern United States, after making landfall in the Gulf Coast, and impacted parts of Massachusetts with rain and wind.
Contents |
[edit] Storm history
A broad mid-tropospheric trough over the southeastern United States spawned an area of convection over the lower Mississippi River Valley on July 13, and drifted southward towards the warm waters of the Gulf of Mexico. As it moved into the Gulf of Mexico, a weak and isolated surface low pressure area formed off of the coast of Louisiana. The circulation in the system steadily expanded, and initially the surface winds and convection were intermittent. On July 16, deep convection increased and organized near the center, and oil rigs and surface buoys reported surface winds of 30 mph (50 km/h). Based on the observations, it is estimated the system developed into Tropical Depression Four on July 16 while about 150 miles (240 km) south of the southwestern Louisiana coastline.[1]
The depression slowly organized for the next day, as it drifted to the northeast. On July 17, the rate of organization and development of deep convection increased considerably, and the depression strengthened into Tropical Storm Danny later that day. From the night of July 17 through July 18, Danny quickly developed deep convection and banding features in the favorable environment of the Gulf of Mexico, and reached hurricane status later on the 18th. Located between two high pressure systems, Danny continued its unusual July track to the northeast, and crossed over southeastern Louisiana near the Mississippi River Delta. A small storm, Danny continued to strengthen after reaching the coastal waters off Mississippi on the night of the 18th, and attained a peak of 80 mph (130 km/h) early on July 19. The hurricane force winds, however, were secluded to the eyewall. After stalling near the mouth of Mobile Bay on July 19, Hurricane Danny turned to the east, and made its final landfall near Mullet Point, Alabama later that day.[1]
The storm rapidly weakened as it continued northward, and degenerated into a tropical depression by July 20. The weak depression moved through Alabama, Georgia, South Carolina, and North Carolina, maintaining a well-defined cloud signature. Due to a front behind the system, Danny strengthened baroclinically over North Carolina to a tropical storm on July 24. This is quite rare for a tropical cyclone, but occurred possibly due to having a good inflow from a baroclinic source. Danny entered the Atlantic Ocean, north of the North Carolina-Virginia border, near Virginia Beach. It quickly reached a secondary peak of 60 mph (96 km/h), and continued rapidly northeastward towards the waters of the Atlantic. A strong mid to upper-level cyclone turned Danny northward, threatening Massachusetts. It stalled while just 30 miles (48 km) southeast of Nantucket on July 26, turned to the east out to sea, and became extratropical later that day. On July 27, the former hurricane merged with a frontal zone.[1]
[edit] Preparations
The National Hurricane Center issued a hurricane watch on July 17, as Danny strengthened to a tropical storm, for the coasts of Louisiana, Mississippi, and Alabama. When Danny strengthened to a hurricane on July 18, a few hours before its landfall in far southeastern Louisiana, and over a day before landfall in Alabama, it was upgraded to a hurricane warning.[1] Grand Isle mayor Arthur Ballenger ordered the evacuation of the town's 1,500 residents, a decision made due to the large number of tourists on the island and to prevent anyone being unable to leave the island. At the time, the hurricane was expected to cause a 5 foot (1.5 meter) storm surge, potentially flooding the only highway out of the island. Officials distributed sandbags to residents in St. Bernard Parish to seal off roads easily flooded, with officials recommending that residents leave the area.[2]
Prior to the arrival of the hurricane, the governors of Mississippi and Alabama declared disaster emergencies, expecting a 9 foot storm surge and up to 20 inches of rain at that time. 6 shelters were opened in Mobile County, though few attended. Officials also considered opening shelters near local casinos and beaches in Biloxi, Mississippi.[3]
Southeastern Massachusetts also had a tropical storm warning issued, a few hours before sustained tropical storm force winds affected the area and less than than 12 hours before its closest approach to the coastline.[1]
[edit] Impact
Being a small storm, Danny caused a damage toll of only $100 million (1997 USD, $120 million 2005 USD), likely a lower amount than if a larger storm were to repeat it. It caused a total of 4 direct and 6 indirect deaths.[1]
[edit] Louisiana
Like other slow-moving tropical cyclones, the hurricane produced extreme amounts of rainfall over Louisiana.[1] Heavy rain and winds impacted many parishes located east of the city of New Orleans.[3] Much of the extreme rainfall was confined to a small radius near the center of the storm, and limited the flooding, which could have been disastrous if it were widespread.[1][4]Grand Isle and portions of the lower Plaquemines Parish were worst hit in Louisiana. Grand Isle reported a wind gust of 100 mph (160 km/h) and a storm surge of 5.2 feet (1.6 meters). A gage reported a water level of 4.85 feet (1.5 meters) in Venice. Storm tides were 2 to 3 feet (0.6 to 0.9 meters) above normal on average.[4]
At least 10,000 people lost electricity in Louisiana, and 130 boats were damaged or sunk at a large marina in Buras, Louisiana. This occurred after waters surged over 4 feet in a matter of minutes.[3] Grand Isle and Grand Terre Island received erosion on their shores.[5]Around 160 households and 80 businesses reported damage on Grand Isle. Jefferson Parish, on Grand Isle, had $1.5 million (1997 USD, $1.6 million 2006 USD) total in damage. Plaquemines Parish, on Grand Isle, had $3.5 million (1997 USD, $4.4 million 2006 USD) in damage. The greatest damage in Plaquemines Parish was between Empire and Venice. Within the hurricane protection levees in the parish, trees, power lines, house roofs, and mobile homes had damage inflicted. Localized flooding also occurred in Plaquemines, after about 10 inches of rain. Some highways were flooded, due to storm tides, in lower Terrebonne Parish, and a few roads in St. Bernard and Orleans parishes, which were outside the hurricane protection levees. Damage elsewhere in the extreme southeastern portion of Louisiana was negligible, due to Danny being a small tropical cyclone and a minimal hurricane.[4]
[edit] Mississippi
Eastern Jackson County was the most affected region in Mississippi. Pascagoula reported a wind gust of 35 mph (55 km/h) on July 19. Pascagoula airport reported 7.87 inches of rain from July 17 through July 19. Some streets and a few homes were flooded in far southeastern Jackson County, in areas of poor drainage systems. No significant damage was reported on the coast of Mississippi by emergency management officials.[6]
[edit] Alabama
Extreme amounts of rainfall were produced over Alabama. Dauphin Island had the highest amount of rainfall, 36.71 inches (932 mm). Not all the rain was caught in the rain gauge, so the rainfall may have been underestimated. Doppler radar estimates show that around 43 inches (1,090 mm) of rain fell off the coast of Dauphin Island. A storm surge of over 6.5 feet (1.98 m) occurred off of Highway 182, midway between Gulf Shores, and Fort Morgan, Alabama, in addition to the rainfall. Unusually, when the storm stalled off the coast of Alabama, prevailing northerly winds forced the water out of Mobile Bay, causing tides to be two feet (0.61 m) below normal. Observers noted that, with the exception of river channels, it would be possible to walk across the bay. In addition, three tornadoes occurred in Alabama, one being in Orange Beach, another in Opelika, while the other one occurred in Port Alabama.[1] A couple of tornadoes also caused minimal damage.[7]
Despite its effects in the northern Gulf of Mexico, only one person was directly killed from the storm there, a man drowning off the coast when he fell off his sailboat near Fort Morgan, Alabama. One indirect casualty also occurred in the area, when a man had a heart attack while trying to secure a boat off the Alabaman coast during the storm.[1] Numerous roads became flooded and impassable for several days, south and along I-10 in Mobile, south and central Choctaw, and Baldwin counties. Along the Fowl and Fish rivers, in Mobile and Baldwin counties respectively, significant damage to homes occurred due to flooding. Most roads on Dauphin Island were flooded in over a foot of water. A few homes were close to falling into Mobile Bay, and one home had to be moved backwards towards land to prevent it's destruction.[8] At the peak of the storm in Alabama, at least 44,000 people were without power in Mobile and Baldwin counties. In rural Choctaw County, north of Mobile, several families were rescued from flooded roads and trapped cars.[5]The majority of houses and businesses on Dauphin Island and buildings from the western shore of Mobile Bay, and from Fort Morgan east to Orange Beach had roof damage. $60.5 million (1997 USD, $70.0 million 2006 USD) was done total in property damage in Alabama. In Alabama, pecan and pine tree damage ending up costing $2.5 million (1997 USD, $3.1 million 2006 USD).[8]
[edit] Florida
Some damage to the cotton crop occurred in Escambia County. Otherwise in northwestern Florida, very little damage resulted from the storm.[8]The Panama City area had some minor fresh water flooding.[9]
[edit] East Coast
Though Danny's impact was severely reduced when it reached Georgia and the Carolinas, it still managed to cause 8-12 inches (203.2-304.8 mm) of rain as it drifted through the western portions of the states. A severe thunderstorm cell in South Carolina produced five tornadoes that touched down, one of which killed a woman in her destroyed duplex while passing through Lexington County.[1]A F2 tornado began 4 miles northeast of Gaston, South Carolina, which ended 7 miles northeast of Gaston, with a width of 200 yards (183 meters) and a length of 4 miles (6.5 kilometers), caused $942,000 (1997 USD, $1.2 million 2006 USD) in damages. It killed one person, injured 6 others, destroyed 2 houses, 2 apartments, and 7 mobile houses, damaging many others.[10] Several tornadoes and waterspouts were spawned over Virginia; most of them occurred in Norfolk, Portsmouth, and Hampton.[11]A F1 tornado occurred 1 mile south of Norfolk, with a width of 50 yards (46 meters) and a length of 1 mile, caused $400,000 (1997 USD, $503,000 2006 USD) in damages. It destroyed one car wash, six other businesses had major roof damage, and one other house had damage.[12] Rainfall in Fayetteville measured 2.85 inches (72.4 mm) of rain, while most of southern New England received approximately 3 inches (76.1 mm) of rain.[13]
The heavy rains caused two people to drown in Charlotte. A girl drowned after being swept into a creek by the floodwaters. The other one was a woman who drowned from the floodwaters while in her car. Four indirect deaths occurred from traffic accidents during the storm's onslaught in Georgia.[1] The tornado in Portsmouth wiped out a car wash, caused six other businesses to suffer lesser damage, including a lumber company that had its roof torn off, and one large truck big-rig wheeler overturned. A severe drought had been in place in the Mid-Atlantic States during the month of July. Copious rainfall amounts helped bring a minor relief to the drought. Strong winds were experienced in southeastern Massachusetts, though damage was minor.[14] The minor damage included minimal flooding, power outages, and downed tree limbs.[9]
[edit] Aftermath
Debris remained in the inland waters of Alabama, at least up until August 12, 1997. Endangered or threatened sea turtles, which all within U.S waters are identified as, lived in these waters. Specialized turtle exclusion devices, known as TED's, or specialized nets that allowed the turtles to escape them, were required before Danny for shrimp trawlers. The Director of the Marine Resources Division of the Alabama Department of Conservation and Natural Resources said that the "inordinate amount of debris is causing extraordinary difficulty with the performance of (TED's) in these areas." Therefore, the United States Environmental Protection Agency allowed an alternative to the TED's, of shorter tow times of a maximum of 55 minutes from April 1 through October 31, and a maximum of 75 minutes from November 1 through March 31. This was intended to minimize any sea turtle casualties as a result of allowing trawlers to remove the TED's.[15]
The name Danny was not retired by the World Meteorological Organization in the spring of 1998 and it was re-used in the 2003 Atlantic hurricane season. It is currently on the list of names to be used again in the 2009 Atlantic hurricane season.
[edit] Records
The storm dropped 36.71 inches (932 mm) of rain on Dauphin Island, setting the new record for the most tropical or subtropical cyclone related rainfall in the state of Alabama, and is among the largest in the United States.[1] The storm also became the earliest 5th tropical or subtropical storm of a season when it reached tropical storm strength on July 17. This record was broken in the 2005 Atlantic hurricane season when Hurricane Emily first attained tropical storm status on July 12, just five days earlier.[16]
[edit] See also
- List of notable Atlantic hurricanes
- List of New England hurricanes
- List of New Jersey hurricanes
- List of Delaware hurricanes
[edit] External links
- NHC Danny report
- HPC Danny rainfall report
- HPC tropical cyclone rainfall maxima by state
- Hurricane Danny
- Remnants of Danny spawns tornadic thunderstorms
- Virginian-Pilot map of tornado sightings
- Tropical Storm Danny visits Portsmouth
- North Effects
[edit] References
- ^ a b c d e f g h i j k l m Richard J. Pasch (1998). Hurricane Danny Tropical Cyclone Report. National Hurricane Center. Retrieved on 2006-12-28.
- ^ Valerie Voss, Charles Zewe, Reuters (1997). Hurricane Danny skims Louisiana tip, moves northeast. CNN. Retrieved on 2006-12-28.
- ^ a b c Associated Press, Reuters (1997). Hurricane Danny heading for Alabama and Mississippi. CNN. Retrieved on 2006-12-29.
- ^ a b c NCDC (1997). Event Record Details: Hurricane (Louisiana). NCDC. Retrieved on 2007-01-01.
- ^ a b Charles Zewe, Associated Press (1997). Danny drifts north, leaving mayhem in its wake. CNN. Retrieved on 2006-12-31.
- ^ NCDC (1997). Event Record Details: Hurricane (Mississippi). NCDC. Retrieved on 2007-01-01.
- ^ NWS-Birmingham Internet Services Team (2006). NWS-Birmingham Internet Services Team. National Weather Service. Retrieved on 2006-12-31.
- ^ a b c NCDC (1997). Event Record Details: Hurricane (Alabama). NCDC. Retrieved on 2007-01-01.
- ^ a b National Weather Service (1997). Hurricane Danny damage reports. USA Today. Retrieved on 2007-02-04.
- ^ NCDC (1997). Event Record Details: Tornado 307724 (Virginia). NCDC. Retrieved on 2007-01-01.
- ^ National Weather Service (1997). Local Sightings of Tornadoes and Funnel Clouds. Virginian Pilot. Retrieved on 2006-12-28.
- ^ NCDC (1997). Event Record Details: Tornado 313574 (Virginia). NCDC. Retrieved on 2007-01-01.
- ^ Neal Lott, Doug Ross, Axel Graumann, Tom Ross (1997). Hurricane Danny. NCDC. Retrieved on 2006-12-28.
- ^ Tropical Storm Danny Visits Portsmouth! (1997). Retrieved on 2006-12-28.
- ^ National Oceanic and Atmospheric Administration (1997). Sea Turtle Conservation; Shrimp Trawling Requirements. United States Environmental Protection Agency. Retrieved on 2006-12-29.
- ^ NHC Hurricane Research Division (2006-02-17). Atlantic hurricane best track ("HURDAT"). NOAA. Retrieved on 2007-01-2.
|
|
|||||||||||||||||||||||
