The Joint Typhoon Warning Center Tropical Cyclone Best Track Review Process

The Joint Typhoon Warning Center (JTWC) best tracks are an independent source of quality-controlled tropical cyclone (TC) track, intensity and structure data for an area of responsibility that encompasses the western North Pacific, South Pacific and Indian Ocean basins. The multi-staged best track quality control process (also known as “best tracking”) leverages expert forecaster assessments of a diverse set of data, including in-situ observations, satellite imagery, and independent estimates of TC parameters to ensure the highest possible level of accuracy and reliability, noting that routine aerial reconnaissance is not available in JTWC basins. Published final best track data are consistent in both format and quality across all basins.

The JTWC best tracking process has changed over the years, primarily due to variability in available datasets (generally, improvements) and personnel resources. However, the process has consistently featured multi-stage reviews. Position, intensity and, more recently, wind radii have traditionally received the most scrutiny during the review process. This work presents an overview of the JTWC best tracking process in its current form. It will highlight key considerations associated with variability in the best track review process and overarching data quality, with the goal of providing users relevant insights to support assessments and application of the data.