1.1. Introduction

The Hurricane Analysis and Forecast System (HAFS) is the Unified Forecast System (UFS) Hurricane Application. HAFS is the FV3-based multi-scale model and data assimilation system capable of providing tropical cyclone (TC) analyses and forecasts of the inner core structure of TCs (including hurricanes and typhoons). HAFS capabilities are key to improving size and intensity predictions, as well as predictions of the large-scale environment that is known to influence a TC’s motion. HAFS development targets an operational analysis and forecast system for hurricane forecasters with reliable, robust and skillful guidance on TC track and intensity (including rapid intensification), storm size, genesis, storm surge, rainfall, and tornadoes associated with TCs. It will provide an advanced analysis and forecast system for cutting-edge research on modeling, physics, data assimilation, and coupling to earth system components for high-resolution TC predictions within the outlined Next Generation Global Prediction System (NGGPS)/Strategic Implementation Plan (SIP) objectives of the Unified Forecast System (UFS). Currently, HAFS is under active development with collaborative efforts among NCEP/EMC, AOML, GFDL, GSL, ESRL/NESII, OFCM/AOC, DTC, NCAR, and the broader research community.

For information about how to contribute to HAFS development, please review the code repository governance.

The HAFS repository is located at https://github.com/hafs-community/HAFS.