Upgrade of NOS Lake Ontario Operational Forecast System to FVCOM: model development and hindcast skill assessment

NOS Lake Ontario Operational Forecast System (LOOFS) is a 3-D lake numerical forecast modeling system which uses near real-time atmospheric analyses, river observations, and numerical weather prediction model forecast guidance to generate hourly nowcasts and short-range forecast guidance of 3-D water temperatures and currents and two-dimensional water levels for Lake Ontario. The present operational LOOFS uses the Great Lakes version of the Princeton Ocean Model (POMGL) as its core numerical oceanographic forecast model with a horizontal resolution of 5 km (3.1 mi) and 21 vertical sigma levels out to 60 hours. A new version of LOOFS has been developed using the Finite Volume Community Ocean Model (FVCOM) with a horizontal resolution ranging from approximately 200 m (0.2 mi) near the shore to about 2.5 km (1.6 mi) offshore and with 21 vertical sigma levels with an integrated, unstructured version of the Los Alamos Community Ice CodE (UG-CICE).