Major revisions to the Atlantic basin hurricane database (or HURDAT) have just been completed for the second half of the 19th Century and early 20th Century. HURDAT is the official record of tropical storms and hurricanes for the Atlantic Ocean, Gulf of Mexico and Caribbean Sea, including those that have made landfall in the United States. This database is utilized for a wide variety of purposes: setting of appropriate building codes for coastal zones, risk assessment for emergency managers, analysis of potential losses for insurance and business interests, intensity forecasting techniques, verification of official and model predictions of track and intensity, seasonal forecasting, and climatic change studies.
There are many reasons why a re-analysis of the HURDAT dataset was both needed and timely. HURDAT contained many systematic and random errors that needed correction. Additionally, as our understanding or tropical cyclones had developed, analysis techniques at the National Hurricane Center changed over the years, and led to biases in the historical database to studies concerned with landfalling events was lack of exact location, time and intensity information at landfall. Finally, recent efforts led by the late Jose Fernandez-Partagas to uncover previously undocumented historical tropical cyclones in the mid-1800's to early 1900's have greatly increased our knowledge of these past events, which also had not been incorporated into the HURDAT database.
Over 5000 additions and alterations are now approved for the 1851 to 1910 era by the National Hurricane Center's Best Track Change Committee. (This same process was utilized for the upgrade of 1992's Hurricane Andrew to a Category 5 on the Saffir-Simpson Hurricane Scale last August.) This work on historical hurricanes was originally conducted by the late Jose Fernandez Partagas. Additional analyses, digitization and quality control of the data was carried out by researchers at the NOAA Hurricane Research Division funded by NOAA Office of Global Programs. Over the next two years, this re-analysis will continue to progress through the remainder of the 20th Century.
Highlights:
1. Busiest Hurricane Season Ever for the U.S.: The 1886 hurricane season has been analyzed to be the busiest on record for the continental United States. Seven hurricanes were recorded to have hit the U.S.: a Saffir- Simpson Hurricane Scale Category 2 hurricane into Texas and Louisiana in June, two Category 2 hurricanes into northwest Florida in June, a Category 1 hurricane into northwest Florida in July, the Category 4 "Indianola" hurricane into Texas in August, a Category 1 hurricane into Texas in September, and a Category 3 hurricane into Louisiana in October. The previous busiest hurricane season for the United States was 1985 with six landfalling hurricanes.
2. Extremely busy Decade for the U.S. Atlantic seaboard: The 1890s were one of the busiest decades on record for the Atlantic seaboard of the United States. Four major hurricanes impacted the coast from Georgia northward - the 1893 Category 3 "Sea Islands Hurricane" in Georgia and South Carolina, another 1893 Category 3 in South Carolina and North Carolina, an 1898 Category 4 in Georgia, and a 1899 Category 3 in North Carolina. Only the decade of the 1950s had more strong hurricanes making landfall along this part of the coast, going back to 1851 when reliable records began.
3. Cycles of hurricane activity: These records reflect the existence of cycles of hurricane activity, rather than trends toward more frequent or stronger hurricanes. In general, the period of the 1850s to the mid-1860s was quiet, the late 1860s through the 1890s were busy and the first decade of the 1900s were quiet. (There were five hurricane seasons with at least 10 hurricanes per year in the active period of the late 1860s to the 1890s and none in the quiet periods.) Earlier work had linked these cycles of busy and quiet hurricane period in the 20th Century to natural changes in Atlantic Ocean temperatures.
4. Georgia major hurricanes: During the 20th Century, Georgia did not have even a single major hurricane make a landfall along its coast. However, such absence did not continue back to the 19th Century. In contrast, Georgia experienced three major hurricanes in the later half of the 19th Century: a Category 3 in 1854 near Savannah, the Category 3 "Sea Islands Hurricane" in 1893 that killed 1000-2000 people near Savannah and a Category 4 in 1898 near Brunswick. Knowledge that such strong hurricanes have impacted this portion of the coast (and will undoubtedly hit again) is important for residents of Georgia to plan for the future.(See new NOAA Technical Memorandum by Sandrik and Landsea(2003).)
5. New England major hurricanes: Despite records showing six major hurricanes impacting New England in the 20th Century, the extension of hurricane analyses back to 1851 only show one major hurricane for the region in the second half of the 19th Century: 1869 hurricane which impacted Rhode Island and Connecticut. Thus it was a relatively quiet period for New England from the 1851 to 1910.
6. First time categorization of catastrophic 19th Century U.S. landfalling hurricanes: Several catastrophic hurricanes in U.S. history were categorized for the first time by the Saffir-Simpson Hurricane Scale. These included: the "Chenier Caminanda Hurricane" that struck Louisiana in 1893 and killed about 2000 people was assigned a Category 4 at landfall; the 1893 "Sea Islands Hurricane" killed 1000-2000 people in Georgia and South Carolina was ranked a Category 3 for its impact in both states; a hurricane in 1881 that also impacted Georgia and South Carolina and killed about 700 people was assigned Category 2 status. These hurricanes rank #2, 4 and 5, respectively, in the largest number of fatalities for U.S. landfalling tropical storms and hurricanes ever.
7. Strongest U.S. landfalling hurricane of the 1851 to 1910 era: The 1886 "Indianola" hurricane was analyzed as having 155 mph maximum sustained winds, a Saffir-Simpson Hurricane Scale Category 4 (approaching Category 5) and was the strongest to strike the United States between 1851 and 1910. This hurricane destroyed the town of Indianola, Texas due to its winds and 15' storm surge and the town was never rebuilt. This was also the strongest hurricane of record anywhere in the Atlantic, Gulf of Mexico or Caribbean Sea during the same time period. (No Category 5 hurricanes were recorded to have hit the United States between 1851 and 1910. However, records are somewhat incomplete along in Gulf coast and Florida because there were some coastal regions with few to no inhabitants, thus there may have been some systems mis-diagnosed in intensity in that period.) 31 major (Category 3, 4 and 5) hurricanes are recorded to have hit the United States from 1851 to 1910.
8. Longest lasting hurricane on record: Storm #3 (also known as the "San Ciriaco" hurricane for its impact in Puerto Rico in 1899 has been re-analyzed to now tie the record for longest lasting tropical cyclone in the Atlantic basin. It began on August 3 in the tropical North Atlantic, hit Puerto Rico as a Category 4 hurricane on the 8th, hit North Carolina as a Category 3 hurricane on the 18th, transformed into an extratropical system north of Bermuda on the 21st, redeveloped into a tropical storm on the 26th, went through the Azores Islands as a Category 1 hurricane on the 3rd of September and finally dissipated as an extratropical storm on the 4th. It was a storm system for 33 days and a tropical storm or hurricane for 28 of those days. This ties the record with Hurricane Ginger of 1971, which also was a tropical cyclone for 28 days.
9. Most hurricanes ever in one day: On August 22, 1893, four hurricanes were occurring simultaneously: storm #3 approaching Nova Scotia, Canada, storm #4 between Bermuda and the Bahamas, storm #6 northeast of the Lesser Antilles, and storm #7 west of the Cape Verde Islands. Storm #4 would end up making a direct hit on New York City as a Category 1 hurricane two days later and storm #6 ending up hitting Georgia and South Carolina as a Category 3 hurricane (the "Sea Islands Hurricane") and killing 1000-2000 people. The only other known date with four hurricanes occurring at the same time was September 25, 1998, when hurricanes Georges, Ivan, Jeanne and Karl were in existence.
Link:
http://www.aoml.noaa.gov/hrd/hurdat/
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