![]() Finally, asynpotic points (primarily to denote times of landfall as well as peak intensities that occurred at times other than the synoptic hours) have been incorporated into the best tracks for the years 1851–19 onward. Size information has been included in the best track data since 2004. Beginning in 1979, central pressures have been estimated for every synoptic time. Originally, central pressure best track values were only included into HURDAT if there was a specific observation that could be used explicitly as the best track value. Prior to 1956, best track information was analyzed only once or twice a day interpolation was used to obtain best-track estimates for the remaining synoptic times when the HURDAT database was constructed in the early 1980s ( Jarvinen et al. Best track intensity and position estimates have been provided for every synoptic time (0000, 0600, 1200, and 1800 UTC) for all tropical storms, hurricanes, and subtropical storms since 1956 ( Jarvinen et al. The NHC develops best tracks for intensity, 1 central pressure, position, and size 2 with a precision of 5 kt (1 kt = 0.5144 m s −1), 1 mb, 0.1° latitude/longitude, 5 n mi, 5 n mi, and 5 n mi, respectively. Best tracks-Definition, content, and procedures Finally, we discuss implications of the uncertainty estimates for NHC analysis/forecast products, as well as for the predictability goals of the Hurricane Forecast Improvement Program ( Gall et al. ![]() ![]() A similar survey conducted in 1999 provides some insight into changes in dataset quality during the last decade. This current work estimates the uncertainties through a survey of the best track authors, the NHC Hurricane Specialists, and compares the survey results to independently derived estimates from Torn and Snyder (2012). Given the widespread use of HURDAT for meteorological, engineering, and financial decision making, it is surprising that very little has been published regarding the uncertainties inherent in the database Torn and Snyder (2012) is a notable exception. 1992), analysis of potential losses for insurance and business interests ( Malmquist and Michaels 2000), and climatic change studies ( Knutson et al. These analyses (apart from those for size) make up the database known as the hurricane database (HURDAT) and have been used for a wide variety of applications: verification of official and model predictions of track and intensity ( McAdie and Lawrence 2000), development of intensity forecasting techniques ( DeMaria 2009), seasonal forecasting ( Klotzbach 2007), setting of appropriate building codes for coastal zones ( American Society of Civil Engineers 1999), risk assessment for emergency managers ( Jarrell et al. 1984), and represent the official historical record for each storm. “Best tracks” are National Hurricane Center (NHC) poststorm analyses of the intensity, central pressure, position, and size of tropical and subtropical cyclones ( Jarvinen et al.
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