Operational wave forecasting for extreme conditions in the Arabian Sea-A comparison with buoy and satellite data

An operational wave forecasting system forced with Global Forecast System (GFS) winds was presented and evaluated for the Arabian Sea. WAVEWATCH III (WWIII) model was used for wave forecasting. Several simu-lations were executed using different input-dissipation parameterizations embedded in WWIII including ST2, ST3, ST4 and ST6 packages for the period of southwest monsoon and two tropical storms in the Arabian Sea. Performance of forecasting system with different source term packages were evaluated by comparing the fore-casted significant wave heights (Hs) with the altimeter-derived Hs and buoy data. Results indicated that time series of the forecasted data derived from different source term packages are well adapted to those of the measured ones at buoy location during southwest monsoon. However, ST3 and ST4 packages outperform the others in terms of forecasting Hs in the entire Arabian Sea as well as buoy location. Also, the forecasted Hs are reliable up to 72-hr lead time. Performance evaluation during the studied tropical cyclones showed that it is not possible to make a general conclusion about the best parameterization. However, the forecast system forced with GFS winds was capable of simulate the peak values of Hs -although with time lag -during the tropical cyclones.