Trapped-fetch waves with tropical cyclones have a single dominant spectral mode: in the direction of storm motion. Accordingly, single spectrum wave generators, analogous to first generation wave growth equations, are sufficient for producing accurate wave height forecasts . . . as long as the wind forecasts are of high quality.

Refinements of the Canadian Hurricane Centre (CHC) parametric hurricane wind model (PHWM) have made available higher quality wind fields, both for forecasting and hindcasting. As well, refinement of the CHC trapped-fetch wave model (TFWM) – driven by the PHWM – has afforded greater success at capturing the largest trapped-fetch waves with tropical cyclones.

The PHWM runs on a Linux platform forecaster workstation, allowing for forecaster intervention in the hurricane parameters. Following intervention, the TFWM can be rerun to generate new wave trajectories that incorporate the refined storm parameters (such as track, wind speed, and central pressure). Operational runs to generate maximum possible wave heights and trajectories for each hour throughout a storm’s history, or forecast, take a maximum of 45 seconds. This gives the operational advantage of being able to make storm parameter adjustments close to a bulletin deadline, thereby affording a confident prediction of storm-waves resonance to be available for consideration prior to issue time.

This presentation will highlight the model and its changes since it was presented at the 24th Conference on Hurricanes and Tropical Meteorology in 2000 and will demonstrate its utility by showing operational output for all Atlantic tropical cyclones for 2003 as well as select storms from the recent past.