HURDAT

The Atlantic hurricane database

During 1959, a technical paper was published by the United States Weather Bureau, which consolidated several sources of records in to a single publication. These sources included annual summaries that had been published in the Monthly Weather Review at various times since 1922, unpublished materials from the Hurricane forecast offices and other studies on hurricanes and hurricane climatology back to around 1886. While combining the sources, position errors of over 100 mi were found for several hurricanes shown in more than one source. Therefore, the positions of all of the systems that were considered to have tropical characteristics, were compared with the historical weather maps of the daily synoptic series. The most reliable positions and intensities were then plotted on a series of annual track charts, before being reviewed by the hurricane forecast centers, Extended Forecast Section and the National Hurricane Research Project. The most accurate and consistent locations from the reviews were then plotted on the maps and published. This dataset was subsequently updated during 1965, which extended the dataset back to 1871 and forwards to 1963 based on additional material.

At around this time, NASA's Apollo program requested data on the climatological impacts of tropical cyclones on launches of space vehicles at the Kennedy Space Center. The basic data was taken by the authors from the National Weather Records North Atlantic Tropical Cyclone deck number 988, which was updated and corrected to include data from 1886 to 1968. As a result of this work, a requirement for a computerized tropical cyclone database at the National Hurricane Center was realized, which led to the prediction of tropical cyclone motion out through 72 hours. Over the next few years, HURDAT was extensively revised, by both the NHC and the National Climatic Center, before it was published at irregular intervals. Over the next couple of decades, it became obvious that the database needed to be revised because it was incomplete, contained significant errors, or did not reflect the latest scientific understanding regarding the interpretation of past data. Charles J Neumann subsequently documented several of these problems and obtained a grant, to start addressing them in a programme that was eventually called the Atlantic Hurricane Database Re-analysis Project.

During the 1990s, Jose Fernandez-Partagas led efforts to document previously undocumented tropical cyclones from the mid 1800s until the early 1900s, by using lists of previous hurricanes, books and newspapers. After his death in 1997, the results of his efforts were built upon by the Atlantic reanalysis team, before being checked by NHC's Best Track Committee and added in to the Atlantic HURDAT in 2001 and 2003.

Both the Atlantic and Eastern Pacific HURDAT Databases are in the process of being re-analysed by the NHC, as they contain several random and systematic errors that have become apparent as analysis techniques have developed over the years. For the Atlantic HURDAT efforts to re-analyse the whole of the period between 1851 to the end of the 20th Century got under way in 2001 when data for the years 1851 to 1856 were added to the database. These additions and changes were based on the groundbreaking work of the late Jose Fernandez-Partagas, who uncovered numerous, previously undocumented, hurricanes from the late 19th and early 20th centuries. The second time the database was updated was August 2002 when Hurricane Andrew was upgraded to a Category 5 hurricane. In addition to these changes additional analyses, digitization and quality control of the data was carried out by researchers at the NOAA Hurricane Research Division. By 2010, re-analysis had been completed as far as the 1930 Atlantic season.

In 2013, the archive's format was significantly changed to include non-synoptic best track times, non-developing tropical depressions and wind radii.

The Eastern and Central Pacific hurricane database

The Eastern Pacific best track database was initially compiled on magnetic tape in 1976 for the seasons between 1949 and 1975, at the NHC to help with the development of two tropical cyclone forecast models, which required tracks of past cyclones as a base for its predictions. The database was based on records held by the United States Navy and were interpolated from 12 hourly intervals to 6 hourly intervals based on a scheme devised by Hiroshi Akima in 1970. Initially tracks for the Central Pacific region and tracks for tropical depressions that did not develop into tropical storms or hurricanes were not included within the database. After the database had been created Arthur Pike of the NHC made some internal adjustments, while in 1980 a review was made by Arnold Court under contract from the United States National Weather Service and resulted in additions and/or modifications to 81 tracks in the database. Between 1976 and 1987, the NHC archived best track data from the Eastern Pacific Hurricane Center, and in 1982 started including information on Central Pacific tropical storms and hurricanes started to be included in the database based on data from the Joint Typhoon Warning Center and research done by Samuel Shaw of the Central Pacific Hurricane Center in 1981. The format of the database was completely revised by the NHC in 1984, so that the format could resemble the Atlantic database before they took over the warning responsibility from the EPHC for the Eastern Pacific in 1988.

In 2008 and in 2013, several revisions were made to the database to extend tracks over land, based on reports in the Mariners Weather Log and extrapolation of the tracks since the EPHC stopped issuing advisories on systems before they made landfall. The archive's format was significantly changed in 2013 to include non-synoptic best track times, non-developing tropical depressions and wind radii. In February 2016, the NHC released the 1959 Mexico hurricane's reanalysis, which was the first system to be reassessed using methods developed for the Atlantic reanalysis process.

Reanalysis projects

After the HURDAT databases were created, it became obvious over the next couple of decades that HURDAT needed to be revised because it was incomplete, contained significant errors, or did not reflect the latest scientific understanding regarding the interpretation of past data.

In 2013, the archive's format was significantly changed to include non-synoptic best track times, non-developing tropical depressions and wind radii. During March 2014, the Atlantic HURDAT was updated with the results of the reanalysis for the seasons between 1946 and 1950, with nine tropical storms added to the database. Hurricane Camille's reanalysis was expedited and published during April 2014, after the National Hurricane Center management realized a need to answer the question: "Which is the strongest hurricane to have struck the United States?" During 2015 and 2016, HURDAT was revised with the results of the reanalysis for the seasons between 1951 and 1955, with 12 new tropical storms added to the database.

References

References

1. (1959). "North Atlantic Tropical Cyclones Tracks and Frequencies of Hurricanes and Tropical Storms 1886–1958". United States Weather Bureau.
2. (1965). "Tropical Cyclones of the North Atlantic Ocean Tracks and Frequencies of Hurricanes and Tropical Storms 1871–1963". United States Weather Bureau.
3. (1968). "Probability of Tropical Cyclone Induced Winds at Cape Kennedy".
4. (June 1978). "A Tropical Cyclone Data Tape for the North Atlantic Basin, 1886–1977: Contents, Limitations, and Uses". United States National Oceanic and Atmospheric Administration's National Weather Service.
5. Neumann, Charles J.. (March 26, 1978). "Tropical cyclones of the North Atlantic Ocean, 1871-1977 /". Asheville, N.C. : U.S. Department of Commerce.
6. (February 11, 2016). "Solving the Jigsaw Puzzle of Hurricane History".
7. (December 25, 2007). "A Fitting Resting Place for a Man of Hurricanes : The Alabama Weather Blog".
8. (April 1995). "A Reconstruction of Historical Tropical Cyclone Frequency in the Atlantic from Documentary and Other Historical Sources 1851 to 1880 Part I: 1851-1870". [[Climate Diagnostics Center]].
9. "NOAA News Online (Story 2005)".
10. (2004). "Hurricanes and Typhoons Past, Present, and Future". [[Columbia University Press]].
11. (January 2000). "Comments of and replies to the National Hurricane Center Best-Track Change Committee".
12. ["Hurricanes and Typhoons — Past, Present and future"]({{google books). Columbia University Press.
13. Kimberlain, Todd B. (April 16, 2012). "Re-analysis of the Eastern North Pacific HURDAT".
14. (April 2013). "The revised Atlantic hurricane database (HURDAT2)". United States National Oceanic and Atmospheric Administration's National Weather Service.
15. (August 1977). "Statistical Guidance for the Prediction of Eastern North Pacific Tropical Cyclone Motion — Part I". United States National Oceanic and Atmospheric Administration's National Weather Service — Western Region.
16. (August 1982). "A Compilation of Eastern and Central North Pacific Tropical Cyclone Data". United States National Oceanic and Atmospheric Administration's National Weather Service.
17. (February 1981). "Eastern North Pacific Tropical Cyclone Occurrences during Intra Seasonal Periods". United States National Oceanic and Atmospheric Administration's National Weather Service — Western Region.
18. (September 1984). "A Tropical Cyclone Data Tape for the Eastern and Central North Pacific Basins, 1949–1983: Contents, Limitations, and Uses". United States National Oceanic and Atmospheric Administration's National Weather Service.
19. Sheets, Robert C. (June 1990). "The National Hurricane Center — Past, Present, and Future". Weather and Forecasting.
20. National Hurricane Center. (April 2015). "Revisions made to EPAC HURDAT". United States National Oceanic and Atmospheric Administration's National Weather Service.
21. (April 2013). "The revised Northeast and North Central Pacific hurricane database (HURDAT2)". United States National Oceanic and Atmospheric Administration's National Weather Service.
22. (February 4, 2016). "Re-analysis of the 1959 Manzanillo Mexico Hurricane Landfall intensity changed from category 5 to category 4". United States National Hurricane Center.
23. (March 2014). "Atlantic hurricane best track (HURDAT) Meta Data". United States National Oceanic and Atmospheric Administration's Office of Oceanic & Atmospheric Research.
24. Landsea, Chris. (March 25, 2014). "RE-ANALYSIS OF 1946 TO 1950 ATLANTIC HURRICANE SEASONS COMPLETED". [[National Oceanographic and Atmospheric Administration]].
25. (April 21, 2015). "A Reanalysis of Hurricane Camille". American Meteorological Society.
26. (April 1, 2014). "Re-analysis of 1969's Hurricane Camille Completed: Catastrophic hurricane now ranks as second strongest on record". National Oceanic and Atmospheric Administration.
27. Landsea, Chris. (May 18, 2015). "RE-ANALYSIS OF 1951 TO 1955 ATLANTIC HURRICANE SEASONS COMPLETED". [[National Oceanographic and Atmospheric Administration]].