Home > Administrative Offices > Finance and Administration > Environmental and Occupational Safety >Safety Tips > Hurricane Preparedness > Inland Flooding > Historical Inland Flooding Events
environmental and occupational safety
Tropical Storm Allison 2001
Allison's long and complex career began on 5 June as an area of disturbed weather over the northwestern Gulf of Mexico developed into a tropical storm. The storm made landfall near Freeport, Texas later that day. Allison weakened to a depression on the 6th, while drifting northward, then it made a slow loop over southeastern Texas from the 7th to the 9th. The cyclone moved into the Gulf of Mexico on the 10th and acquired subtropical characteristics. It then moved east-northeastward over southeastern Louisiana on the 11th, where it re-intensified into a subtropical storm. Allison weakened back to a subtropical depression on the 12th while continuing east-northeastward, and this motion carried it to southeastern North Carolina by the 14th where it again stalled. The cyclone drifted northward to northeastward drift over land on the 15th and 16th. This was followed by a faster northeastward motion on the 17th as the center emerged into the Atlantic. Allison regained subtropical storm strength later that day before becoming extratropical on the 18th southeast of Cape Cod. The system dissipated southeast of Nova Scotia the next day.
Allison brought tropical-storm-force winds and above normal tides to portions of the Texas and Louisiana coasts. However, the greatest legacy of the cyclone was the widespread heavy rains and resulting floods along the entire path of the cyclone (figure). Houston, Texas, was the worst affected area, as the Port of Houston reported 36.99 inches and several other locations reported more than 30 inches (figure). The storm also spawned 23 tornadoes. Allison was responsible for 41 deaths and at least $5 billion in damage in the United States, making it the deadliest and costliest U. S. tropical storm of record.
Hurricane Floyd 1999
Floyd was first detected as a tropical wave that moved off the African coast on September 2. The system developed into a tropical depression over the tropical Atlantic on September 7. Moving steadily west-northwestward, the system became a tropical storm the next day and a hurricane on the 10th. A northwestward turn late on the 10th was followed by a westward turn on the 12th, with the second turn marking the time Floyd started strengthening in earnest. It became a Category 4 hurricane on September 13 as it approached the central Bahama Islands. A west-northwestward turn late on the 13th took the center through the northeastern Bahamas. This was followed by a gradual turn to the north-northeast, which brought the center to the North 
Carolina coast near Cape Fear on September 16 as a Category 2 hurricane. Floyd continued north-northeastward along the coast of the Mid-Atlantic into New England, where the storm became extratropical on the 17th. The remnants of Floyd merged with a large non-tropical low on September 19.
While wind gusts of 120 mph and storm surges of 9 to 10 ft were reported from the North Carolina coast, Floyd will be most remembered in the United States for its rainfall. The combination of Floyd and a frontal system over the eastern United States produced widespread rainfalls in excess of 10 inches from North Carolina northeastward, with amounts as high as 19.06 inches in Wilmington, North Carolina and 13.70 inches at Brewster, New York. These rains, aided by rains from Tropical Storm Dennis two weeks earlier, caused widespread severe flooding that caused the majority of the $3 to 6 billion in damage caused by Floyd. These floods also were responsible for 50 of the 56 deaths caused by Floyd in the United States. Floyd also caused damage in the Bahamas, with one death reported.
Tropical Storm Alberto 1994
Alberto was first detected as a tropical wave that moved off the African coast on 18 June. The wave moved into the western Caribbean by late June and formed into a tropical 
depression near the western tip of Cuba on June 30. The cyclone moved northwest through July 1 as it became a tropical storm, then it turned northward. This motion continued until the cyclone made landfall in the western Florida Panhandle on the 4th. Alberto then moved north-northeastward into western Georgia, where it did a loop on the 5th and 6th. The cyclone finally dissipated over central Alabama on July 7.
Alberto's winds and tides produced only minor damage at the coast, but the excessive rains that fell in Georgia, Alabama, and western Florida were another story. Amounts exceeded 10 inches in many locations, with the maximum being the 27.61 inch storm total at Americus, GA (including 21 inches in 24 hours). Severe flooding resulted over large portions of southern Georgia, western Alabama, and the western Florida Panhandle. The floods were responsible for 30 deaths and $500 million in damage.
Tropical Storm Claudette 1979
Claudette was first detected as a tropical wave that moved off the African coast on July 11. The wave spawned a tropical depression on July 16 that briefly became a tropical storm the next day as it approached the Leeward and Virgin Islands. Claudette weakened to a tropical depression and then a tropical wave while passing near Puerto Rico on the 18th, and little re-development occurred until the system moved into the southeastern Gulf of Mexico on the 21st. Claudette regained tropical storm strength over the western Gulf on July 23 and made landfall the next day near the Louisiana-Texas border. It made a slow loop over southeastern Texas on the 24th and 25th, followed by a northward motion into Oklahoma on the 27th. The remnants of Claudette turned eastward and merged with a frontal system over West Virginia on July 29.
Claudette produced tropical storm conditions along portions of the Texas and Louisiana coasts, but the storm will be most remembered for its rainfall. Widespread amounts in excess of 10 inches occurred over portions of southeastern Texas and southwestern Louisiana, with several local amounts in excess of 30 inches. An observer west of Alvin, Texas reported 43 inches in 24 hours, which is a United States record for 24 hour rainfall amount. The storm total at that location was 45 inches. The rains produced severe flooding that was responsible for one death and $400 million in damage. The storm also produced heavy rains over portions of Puerto Rico that were responsible for one death.
Hurricane Agnes 1972
The large disturbance that became Agnes was first detected over the Yucatan Peninsula of Mexico on June 14. The system drifted eastward and became a tropical depression later that day and a tropical storm over the northwestern Caribbean on the 16th. Agnes turned northward on June 17 and became a hurricane over the southeastern Gulf of Mexico the next day. A continued northward motion brought Agnes to the Florida Panhandle coast on June 19 as a Category 1 hurricane. Agnes turned northeastward after landfall and 
weakened to a depression over Georgia. However, it regained tropical storm strength over eastern North Carolina on June 21 and moved into the Atlantic later that day. A northwestward turn followed, and a just-under-hurricane-strength Agnes made a final landfall on the 22nd near New York, New York. The storm merged with a non-tropical low on June 23rd, with the combined system affecting the northeastern United States until the 25th.
Agnes was barely a hurricane at landfall in Florida, and the effects of winds and storm surges were relatively minor. The major impact was over the northeastern United States, where Agnes combined with the non-tropical low to produce widespread rains of 6 to 12 inches with local amounts of 14 to 19 inches. These rains produced widespread severe flooding from Virginia northward to New York, with other flooding occurring over the western portions of the Carolinas.
Agnes caused 122 deaths in the United States. Nine of these were in Florida (mainly from severe thunderstorms) while the remainder were associated with the flooding. The storm was responsible for $2.1 billion in damage in the United States, the vast majority of which came from the flooding. Agnes also affected western Cuba, where seven additional deaths occurred.
Hurricane Camille 1969
This powerful, deadly, and destructive hurricane formed just west of the Cayman Islands on August 14. It rapidly intensified and by the time it reached western Cuba the next day it was a Category 3 hurricane. Camille tracked north-northwestward across the Gulf of Mexico and became a Category 5 hurricane on August 16. The hurricane maintained this intensity until it made landfall along the Mississippi coast late on the 17th. Camille 
weakened to a tropical depression as it crossed Mississippi into western Tennessee and Kentucky, then it turned eastward across West Virginia and Virginia. The cyclone moved into the Atlantic on August 20 and regained tropical storm strength before becoming extratropical on the 22nd.
A minimum pressure of 26.84 inches was reported in Bay St. Louis, Mississippi, which makes Camille the second most intense hurricane of record to hit the United States. The actual maximum sustained winds will never be known, as the hurricane destroyed all the wind-recording instruments in the landfall area. The estimates at the coast are near 200 mph. Columbia, Mississippi, located 75 miles inland, reported 120 mph sustained winds. A storm tide of 24.6 ft occurred at Pass Christian, Mississippi. The heaviest rains along the Gulf Coast were about 10 inches. However, as Camille passed over the Virginias, it produced a burst of 12 to 20 inch rains with local totals of up to 31 inches. Most of this rain occurred in 3 to 5 hours and caused catastrophic flash flooding.
The combination of winds, surges, and rainfalls caused 256 deaths (143 on the Gulf Coast and 113 in the Virginia floods) and $1.421 billion in damage. Three deaths were reported in Cuba.
Hurricane Connie and Diane 1955
These two hurricanes must be mentioned together. They struck the North Carolina coast only five days apart, and the rains from Connie set the stage for the devastating floods caused by Diane.
Connie was first detected as a tropical storm over the tropical Atlantic on August 3. It moved just north of west for several days, reaching hurricane strength several hundred miles northeast of the Leeward Islands on the 5th. After passing north of the 
Leewards on the 6th, Connie turned northwestward - a motion that continued until the 10th. An erratic, generally north-northwestward motion then brought Connie to the North Carolina coast on August 12 as a Category 3 hurricane. This was followed by a gradual northwestward turn through August 14, when Connie dissipated over the eastern Great Lakes.
Fort Macon, North Carolina reported 75 mph sustained winds with gusts to 100 mph, while a storm surge of up to 8 ft occurred along the coast. There were no reported deaths and the damage in the United States was $40 million. However, the most significant aspect of Connie was the rainfall of up to 12 inches that affected the northeastern United States.
Diane was first detected over the tropical Atlantic on August 7. Moving generally west-northwestward, the cyclone became a tropical storm on the 9th. Diane became a hurricane on August 11, by which time it was moving northwestward. A northward turn occurred on the 12th, followed by a westward turn on the 13th and a west-northwestward motion on the 14th. This motion brought Diane to the North Carolina coast on August 17 as a Category 1 hurricane. The storm turned northward across Virginia, then it turned northeastward and moved back into the Atlantic near Long Island, New York on August 19. Diane became extratropical over the North Atlantic on the 21st.
Hurricane conditions affected only a small part of the North Carolina coast, and the damage from winds and tides was relatively minor. The main impact was heavy rains. Diane poured 10 to 20 inches of rain on areas soaked by Connie just a few days before, producing widespread severe flooding from North Carolina to Massachusetts. The floods were responsible were 184 deaths and $832 million in damage.
*Information adapted from http://www.nhc.noaa.gov/HAW2/english/intro.shtml