This paper by Christopher W. Landsea and James L. Franklin from the National Hurricane Center (NHC) in Miami, Florida, estimates the uncertainties in the "best tracks" of Atlantic basin tropical and subtropical cyclones. Best tracks are post-storm analyses of intensity, central pressure, position, and size, maintained and updated by NHC Hurricane Specialists. The study compares uncertainty estimates from a 1999 survey with those from a 2010 survey to assess changes over the past decade. The results show that: - **Intensity Uncertainty**: Increases moderately with intensity and decreases significantly with the availability of aircraft monitoring compared to satellite-only observations. - **Central Pressure Uncertainty**: Increases moderately with intensity and decreases to much smaller values with the availability of aircraft monitoring. - **Position Uncertainty**: Decreases substantially with increasing intensity and with the availability of aircraft monitoring. - **Wind Radii Uncertainty**: Changes little with intensity but decreases moderately with the availability of aircraft monitoring. The paper also discusses the implications of these uncertainties for NHC analysis and forecast products, particularly in the context of the Hurricane Forecast Improvement Program (HFIP) goals. The findings suggest that while position uncertainties are relatively small, intensity uncertainties may pose challenges to achieving HFIP's forecast goals by 2019. The authors propose potential improvements in monitoring capabilities, such as the use of advanced instruments and next-generation satellite-based scatterometers, to reduce these uncertainties.This paper by Christopher W. Landsea and James L. Franklin from the National Hurricane Center (NHC) in Miami, Florida, estimates the uncertainties in the "best tracks" of Atlantic basin tropical and subtropical cyclones. Best tracks are post-storm analyses of intensity, central pressure, position, and size, maintained and updated by NHC Hurricane Specialists. The study compares uncertainty estimates from a 1999 survey with those from a 2010 survey to assess changes over the past decade. The results show that: - **Intensity Uncertainty**: Increases moderately with intensity and decreases significantly with the availability of aircraft monitoring compared to satellite-only observations. - **Central Pressure Uncertainty**: Increases moderately with intensity and decreases to much smaller values with the availability of aircraft monitoring. - **Position Uncertainty**: Decreases substantially with increasing intensity and with the availability of aircraft monitoring. - **Wind Radii Uncertainty**: Changes little with intensity but decreases moderately with the availability of aircraft monitoring. The paper also discusses the implications of these uncertainties for NHC analysis and forecast products, particularly in the context of the Hurricane Forecast Improvement Program (HFIP) goals. The findings suggest that while position uncertainties are relatively small, intensity uncertainties may pose challenges to achieving HFIP's forecast goals by 2019. The authors propose potential improvements in monitoring capabilities, such as the use of advanced instruments and next-generation satellite-based scatterometers, to reduce these uncertainties.